Hướng dẫn how many keywords in python latest version - có bao nhiêu từ khóa trong phiên bản mới nhất của python
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Mã nguồn: lib/từ khóa.py Lib/keyword.py Show
Mô -đun này cho phép chương trình Python xác định xem một chuỗi là từ khóa hay từ khóa mềm.keyword or soft keyword. từ khóa.iskeyword (s) ¶iskeyword(s)¶Trả về Trình tự chứa tất cả các từ khóa được xác định cho trình thông dịch. Nếu bất kỳ từ khóa nào được xác định chỉ hoạt động khi các câu lệnh Trả về Mới trong phiên bản 3.9. Từ khóa.softkwlist¶softkwlist¶Trình tự chứa tất cả các từ khóa mềm được xác định cho trình thông dịch. Nếu bất kỳ từ khóa mềm nào được xác định chỉ hoạt động khi các câu lệnh Mới trong phiên bản 3.9. Bal Krishna JHA Lượt xem: 2.08K Xuất bản: 24 tháng 1 năm 2020 Sửa đổi lần cuối: 9 tháng 2 năm 2020 Có một số từ dành riêng được định nghĩa trong mọi ngôn ngữ, trong đó mỗi từ có một số chức năng liên quan đến nó. Các chức năng và từ khóa được quyết định bởi các nhà thiết kế ngôn ngữ và người sáng tạo. Trong Python 3.8, có 35 từ khóa. Danh sách các từ khóa tiếp tục thay đổi khi ngôn ngữ phát triển. Một từ khóa mới có thể được giới thiệu hoặc xóa, vì phiên bản mới của Python được phát hành. Ví dụ, trong Python 2.7, đã có & nbsp; 31 từ khóa so với 33 trong Python 3.6.7 và 35 trong Python 3.8.1. Để liệt kê tất cả các từ khóa, bạn có thể sử dụng bất kỳ phương pháp nào: Trong trình thông dịch Python, phương thức trợ giúp cuộc gọi - Nhưng phương pháp trên chỉ bị giới hạn ở chế độ tương tác. Trong trường hợp bạn muốn truy cập danh sách trong tập lệnh, bạn có thể nhập mô -đun từ khóa. Từ khóa trong Python 3.8.1
Được sử dụng để khai báo một biến trong phạm vi toàn cầu Xem bây giờ hướng dẫn này có một khóa học video liên quan được tạo bởi nhóm Python thực sự. Xem cùng với hướng dẫn bằng văn bản để hiểu sâu hơn về sự hiểu biết của bạn: Khám phá các từ khóa trong Python This tutorial has a related video course created by the Real Python team. Watch it together with the written tutorial to deepen your understanding: Exploring Keywords in Python Mỗi ngôn ngữ lập trình đều có các từ dành riêng, hoặc từ khóa, có ý nghĩa và hạn chế cụ thể xung quanh cách sử dụng chúng. Python không khác. Từ khóa Python là các khối xây dựng cơ bản của bất kỳ chương trình Python nào.keywords, that have specific meanings and restrictions around how they should be used. Python is no different. Python keywords are the fundamental building blocks of any Python program. Trong bài viết này, bạn sẽ tìm thấy một giới thiệu cơ bản về tất cả các từ khóa Python cùng với các tài nguyên khác sẽ hữu ích để tìm hiểu thêm về từng từ khóa. Đến cuối bài viết này, bạn sẽ có thể:
Từ khóa PythonTừ khóa Python là những từ dành riêng đặc biệt có ý nghĩa và mục đích cụ thể và có thể được sử dụng cho bất cứ điều gì ngoại trừ những mục đích cụ thể đó. Các từ khóa này luôn có sẵn, bạn sẽ không bao giờ phải nhập chúng vào mã của bạn. Các từ khóa Python khác với các chức năng và loại tích hợp Python. Các chức năng và loại tích hợp cũng luôn có sẵn, nhưng chúng không bị hạn chế như các từ khóa trong việc sử dụng của chúng. Một ví dụ về một cái gì đó bạn có thể làm với các từ khóa Python là gán một cái gì đó cho chúng. Nếu bạn cố gắng, thì bạn sẽ nhận được Kể từ Python 3.8, có ba mươi lăm từ khóa trong Python. Ở đây họ có liên kết đến các phần có liên quan trong suốt phần còn lại của bài viết này: Bạn có thể sử dụng các liên kết này để nhảy vào các từ khóa mà bạn muốn đọc, hoặc bạn có thể tiếp tục đọc cho một tour du lịch có hướng dẫn. Cách xác định từ khóa PythonDanh sách các từ khóa Python đã thay đổi theo thời gian. Ví dụ: từ khóa Trong các phần dưới đây, bạn sẽ học được một số cách để biết hoặc tìm ra từ nào là từ khóa trong Python. Sử dụng IDE với cú pháp làm nổi bậtCó rất nhiều id python tốt ngoài kia. Tất cả chúng sẽ làm nổi bật các từ khóa để phân biệt chúng với các từ khác trong mã của bạn. Điều này sẽ giúp bạn nhanh chóng xác định các từ khóa Python trong khi bạn lập trình để bạn không sử dụng chúng không chính xác. Sử dụng mã trong một bản sao để kiểm tra các từ khóaTrong Python Repl, có một số cách bạn có thể xác định các từ khóa Python hợp lệ và tìm hiểu thêm về chúng. Bạn có thể nhận được danh sách các từ khóa có sẵn bằng cách sử dụng >>> Tiếp theo, như được chỉ ra trong đầu ra ở trên, bạn có thể sử dụng một lần nữa bằng cách truyền trong từ khóa cụ thể mà bạn cần thêm thông tin về. Bạn có thể làm điều này, ví dụ, với từ khóa >>> Tiếp theo, như được chỉ ra trong đầu ra ở trên, bạn có thể sử dụng một lần nữa bằng cách truyền trong từ khóa cụ thể mà bạn cần thêm thông tin về. Bạn có thể làm điều này, ví dụ, với từ khóa
>>> Tiếp theo, như được chỉ ra trong đầu ra ở trên, bạn có thể sử dụng một lần nữa bằng cách truyền trong từ khóa cụ thể mà bạn cần thêm thông tin về. Bạn có thể làm điều này, ví dụ, với từ khóa Python cũng cung cấp một mô -đun >>> def func(): ... print("hello") ... >>> x = func() hello >>> print(x) None 2 để làm việc với các từ khóa Python theo cách lập trình. Mô -đun >>> def func(): ... print("hello") ... >>> x = func() hello >>> print(x) None 2 trong Python cung cấp hai thành viên hữu ích để xử lý các từ khóa:left if not left else right 5 cung cấp một cách tiện dụng để xác định xem một chuỗi cũng là từ khóa.Để có được danh sách tất cả các từ khóa trong phiên bản Python mà bạn đang chạy và để nhanh chóng xác định có bao nhiêu từ khóa được xác định, hãy sử dụng Nếu bạn cần biết thêm về một từ khóa hoặc cần làm việc với các từ khóa theo cách lập trình, thì Python cung cấp tài liệu và công cụ này cho bạn.
Các phần dưới đây tổ chức các từ khóa Python thành các nhóm dựa trên việc sử dụng của chúng. Ví dụ, nhóm đầu tiên là tất cả các từ khóa được sử dụng làm giá trị và nhóm thứ hai là từ khóa được sử dụng làm toán tử. Các nhóm này sẽ giúp bạn hiểu rõ hơn về cách sử dụng từ khóa và cung cấp một cách tốt đẹp để tổ chức danh sách dài các từ khóa Python. Có một vài thuật ngữ được sử dụng trong các phần dưới đây có thể là mới đối với bạn. Họ đã định nghĩa ở đây và bạn nên biết về ý nghĩa của chúng trước khi tiến hành:Sự trung thực đề cập đến việc đánh giá boolean về một giá trị. Sự thật của một giá trị cho thấy giá trị là sự thật hay giả. Sự thật có nghĩa là bất kỳ giá trị nào đánh giá đúng trong bối cảnh Boolean. Để xác định xem một giá trị có phải là sự thật hay không, hãy truyền nó như là đối số cho left if not left else right
>>> val = "" # Truthiness value is `False`
>>> not val
True
>>> val = 5 # Truthiness value is `True`
>>> not val
False
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Trong Python, bạn thường không cần phải chuyển đổi các giá trị để được rõ ràng | Từ khóa | Từ khóa Python |
|---|---|---|
| Để đi sâu hơn về từ khóa Python rất quan trọng và hữu ích này, hãy xem NULL trong Python: Hiểu đối tượng Python tựa Nonetype. | Từ khóa của nhà điều hành: |
Một số từ khóa Python được sử dụng làm toán tử. Trong các ngôn ngữ lập trình khác, các nhà khai thác này sử dụng các biểu tượng như | Toán học toán | Những ngôn ngữ khác |
| Từ khóa Python | Và, ∧ | |
| Hoặc, ∨ | |
| | Không, ¬ |
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
46
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Chứa,
44 is used to determine if both the left and right operands are truthy or falsy. If both operands are
truthy, then the result will be truthy. If one is falsy, then the result will be falsy: >>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
XÁC THỰC
left if not left else right
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Mã Python được thiết kế cho khả năng đọc. Đó là lý do tại sao nhiều nhà khai thác sử dụng các biểu tượng trong các ngôn ngữ lập trình khác là các từ khóa trong Python.
Từ khóa
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Từ khóa Python >>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
44 được sử dụng để xác định xem cả hai toán hạng bên trái và phải là sự thật hay giả. Nếu cả hai toán hạng là sự thật, thì kết quả sẽ là sự thật. Nếu một người là giả, thì kết quả sẽ là giả mạo:
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Lưu ý rằng kết quả của câu lệnh
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> val = "" # Truthiness value is `False`
>>> not val
True
>>> val = 5 # Truthiness value is `True`
>>> not val
False
>>> val = "" # Truthiness value is `False`
>>> not val
True
>>> val = 5 # Truthiness value is `True`
>>> not val
False
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
left if not left else right
>>> val = "" # Truthiness value is `False`
>>> not val
True
>>> val = 5 # Truthiness value is `True`
>>> not val
False
>>> val = "" # Truthiness value is `False`
>>> not val
True
>>> val = 5 # Truthiness value is `True`
>>> not val
False
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Nếu bạn muốn xác định một biểu thức đã làm điều tương tự như biểu thức
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Tuyên bố trên sẽ tạo ra kết quả tương tự như
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Bởi vì
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Để có cái nhìn sâu hơn về
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Từ khóa >>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
46
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Từ khóa Python từ
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>>
>>> val = "" # Truthiness value is `False`
>>> not val
True
>>> val = 5 # Truthiness value is `True`
>>> not val
False
Từ khóa
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> val = "" # Truthiness value is `False`
>>> not val
True
>>> val = 5 # Truthiness value is `True`
>>> not val
False
>>> val = "" # Truthiness value is `False`
>>> not val
True
>>> val = 5 # Truthiness value is `True`
>>> not val
False
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> val = "" # Truthiness value is `False`
>>> not val
True
>>> val = 5 # Truthiness value is `True`
>>> not val
False
>>> val = "" # Truthiness value is `False`
>>> not val
True
>>> val = 5 # Truthiness value is `True`
>>> not val
False
Nếu bạn muốn có được hành vi tương tự mà không cần sử dụng
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Tuyên bố này sẽ trả về kết quả tương tự như
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Từ khóa >>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
47
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Từ khóa Python từ
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> val = "" # Truthiness value is `False`
>>> not val
True
>>> val = 5 # Truthiness value is `True`
>>> not val
False
>>> val = "" # Truthiness value is `False`
>>> not val
True
>>> val = 5 # Truthiness value is `True`
>>> not val
False
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> val = "" # Truthiness value is `False`
>>> not val
True
>>> val = 5 # Truthiness value is `True`
>>> not val
False
>>> val = "" # Truthiness value is `False`
>>> not val
True
>>> val = 5 # Truthiness value is `True`
>>> not val
False
Một ví dụ tốt về việc sử dụng từ khóa
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>>
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Từ khóa
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> val = "" # Truthiness value is `False`
>>> not val
True
>>> val = 5 # Truthiness value is `True`
>>> not val
False
>>> val = "" # Truthiness value is `False`
>>> not val
True
>>> val = 5 # Truthiness value is `True`
>>> not val
False
Nếu bạn muốn có được hành vi tương tự mà không cần sử dụng >>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
46, thì bạn có thể làm như vậy với biểu thức ternary sau:
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Tuyên bố này sẽ trả về kết quả tương tự như
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Từ khóa
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Từ khóa Python từ
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> val = "" # Truthiness value is `False`
>>> not val
True
>>> val = 5 # Truthiness value is `True`
>>> not val
False
>>> val = "" # Truthiness value is `False`
>>> not val
True
>>> val = 5 # Truthiness value is `True`
>>> not val
False
Một ví dụ tốt về việc sử dụng từ khóa
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Từ khóa >>> help("keywords") Here is a list of the Python keywords. Enter any keyword to get more help. False class from or None continue global pass True def if raise and del import return as elif in try assert else is while async except lambda with await finally nonlocal yield break for not 47 hoạt động với tất cả các loại container: danh sách, dicts, bộ, chuỗi và bất cứ thứ gì khác xác định >>> help("pass") The "pass" statement ******************** pass_stmt ::= "pass" "pass" is a null operation — when it is executed, nothing happens. It is useful as a placeholder when a statement is required syntactically, but no code needs to be executed, for example: def f(arg): pass # a function that does nothing (yet) class C: pass # a class with no methods (yet) 12 hoặc có thể được lặp lại.
Từ khóa
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Từ khóa Python từ >>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
25 là một kiểm tra nhận dạng. Điều này khác với toán tử >>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
15, kiểm tra sự bình đẳng. Đôi khi hai điều có thể được coi là bằng nhau nhưng không phải là cùng một đối tượng trong bộ nhớ. Từ khóa >>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
25 xác định xem hai đối tượng có chính xác cùng một đối tượng hay không:
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Điều này sẽ trả về
>>> val = "" # Truthiness value is `False`
>>> not val
True
>>> val = 5 # Truthiness value is `True`
>>> not val
False
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> val = "" # Truthiness value is `False`
>>> not val
True
>>> val = 5 # Truthiness value is `True`
>>> not val
False
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Hầu hết thời gian bạn sẽ thấy
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Nếu các khái niệm này là mới đối với bạn, thì bạn có thể nhận được lời giải thích sâu hơn bằng cách kiểm tra Python ‘! Để tìm hiểu sâu hơn về cách
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Kiểm soát luồng từ khóa:
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Ba từ khóa Python được sử dụng cho luồng điều khiển:
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Từ khóa
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Từ khóa >>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
74 được sử dụng để bắt đầu một câu lệnh có điều kiện. Một câu lệnh >>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
74 cho phép bạn viết một khối mã chỉ được thực thi nếu biểu thức sau >>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
74 là sự thật.
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Cú pháp cho câu lệnh
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
- Tuyên bố
74 là một thành phần quan trọng của hầu hết các chương trình. Để biết thêm thông tin về tuyên bố>>> help("keywords") Here is a list of the Python keywords. Enter any keyword to get more help. False class from or None continue global pass True def if raise and del import return as elif in try assert else is while async except lambda with await finally nonlocal yield break for not
74, hãy xem các câu lệnh có điều kiện trong Python.>>> help("keywords") Here is a list of the Python keywords. Enter any keyword to get more help. False class from or None continue global pass True def if raise and del import return as elif in try assert else is while async except lambda with await finally nonlocal yield break for not - Một cách sử dụng khác của từ khóa
74 là một phần của toán tử ternary Python:>>> help("keywords") Here is a list of the Python keywords. Enter any keyword to get more help. False class from or None continue global pass True def if raise and del import return as elif in try assert else is while async except lambda with await finally nonlocal yield break for not
Đây là phiên bản một dòng của câu lệnh
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Nếu các biểu thức của bạn là các câu lệnh không biến chứng, thì sử dụng biểu thức ternary cung cấp một cách tốt đẹp để đơn giản hóa mã của bạn một chút. Khi các điều kiện trở nên phức tạp, nó thường tốt hơn để dựa vào tuyên bố
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Từ khóa >>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
28
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Tuyên bố
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Lưu ý rằng câu lệnh
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Từ khóa lặp lại: >>> help("pass") The "pass" statement ******************** pass_stmt ::= "pass" "pass" is a null operation — when it is executed, nothing happens. It is useful as a placeholder when a statement is required syntactically, but no code needs to be executed, for example: def f(arg): pass # a function that does nothing (yet) class C: pass # a class with no methods (yet) 71, >>> help("pass") The "pass" statement ******************** pass_stmt ::= "pass" "pass" is a null operation — when it is executed, nothing happens. It is useful as a placeholder when a statement is required syntactically, but no code needs to be executed, for example: def f(arg): pass # a function that does nothing (yet) class C: pass # a class with no methods (yet) 72, >>> help("pass") The "pass" statement ******************** pass_stmt ::= "pass" "pass" is a null operation — when it is executed, nothing happens. It is useful as a placeholder when a statement is required syntactically, but no code needs to be executed, for example: def f(arg): pass # a function that does nothing (yet) class C: pass # a class with no methods (yet) 73, >>> help("pass") The "pass" statement ******************** pass_stmt ::= "pass" "pass" is a null operation — when it is executed, nothing happens. It is useful as a placeholder when a statement is required syntactically, but no code needs to be executed, for example: def f(arg): pass # a function that does nothing (yet) class C: pass # a class with no methods (yet) 74, >>> help("pass") The "pass" statement ******************** pass_stmt ::= "pass" "pass" is a null operation — when it is executed, nothing happens. It is useful as a placeholder when a statement is required syntactically, but no code needs to be executed, for example: def f(arg): pass # a function that does nothing (yet) class C: pass # a class with no methods (yet) 29
Vòng lặp và lặp là các khái niệm lập trình cực kỳ quan trọng. Một số từ khóa Python được sử dụng để tạo và làm việc với các vòng lặp. Chúng, giống như các từ khóa Python được sử dụng cho các điều kiện ở trên, sẽ được sử dụng và nhìn thấy trong mọi chương trình Python bạn gặp. Hiểu chúng và cách sử dụng đúng đắn của họ sẽ giúp bạn cải thiện như một lập trình viên Python.
Từ khóa >>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
71
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Vòng lặp phổ biến nhất trong Python là vòng
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Một ví dụ phổ biến là lặp qua các số một đến năm và in chúng ra màn hình:
>>>
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Trong các ngôn ngữ lập trình khác, cú pháp cho vòng lặp
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Trong Python, vòng lặp
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>>
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
Trong các ngôn ngữ lập trình khác, cú pháp cho vòng lặp
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Trong Python, vòng lặp
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Trong ví dụ này, bạn bắt đầu với danh sách (container) của những người tên. Vòng lặp >>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
71 bắt đầu với từ khóa >>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
71 ở đầu dòng, theo sau là biến để gán từng phần tử của danh sách, sau đó là từ khóa >>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
47 và cuối cùng là container (>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
87).
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Python sườn
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Từ khóa
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Vòng lặp Python từ
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>>
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Trong các ngôn ngữ lập trình khác, cú pháp cho vòng lặp
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Trong Python, vòng lặp >>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
71 giống như một vòng lặp lại trong các ngôn ngữ lập trình khác. Đưa đối tượng để lặp lại, nó gán giá trị của từng lần lặp cho biến:
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Trong ví dụ này, bạn bắt đầu với danh sách (container) của những người tên. Vòng lặp
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Python sườn
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>>
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Trong các ngôn ngữ lập trình khác, cú pháp cho vòng lặp
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Trong Python, vòng lặp >>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
71 giống như một vòng lặp lại trong các ngôn ngữ lập trình khác. Đưa đối tượng để lặp lại, nó gán giá trị của từng lần lặp cho biến:
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Trong ví dụ này, bạn bắt đầu với danh sách (container) của những người tên. Vòng lặp
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Python sườn
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Từ khóa >>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
72
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Vòng lặp Python từ
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Cách dễ nhất để chỉ định một vòng lặp vô hạn trong Python là sử dụng từ khóa
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Để biết thêm các ví dụ về các vòng lặp vô hạn trong hành động, hãy xem chương trình ổ cắm trong Python (Hướng dẫn). Để tìm hiểu thêm về các vòng
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Nhiệm vụ mà nó hiển thị là lặp qua các số từ hai đến chín để tìm các số nguyên tố. Một cách bạn có thể làm điều này là với vòng lặp
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>>
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Bạn có thể sử dụng cờ
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> val = "" # Truthiness value is `False`
>>> not val
True
>>> val = 5 # Truthiness value is `True`
>>> not val
False
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> val = "" # Truthiness value is `False`
>>> not val
True
>>> val = 5 # Truthiness value is `True`
>>> not val
False
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> val = "" # Truthiness value is `False`
>>> not val
True
>>> val = 5 # Truthiness value is `True`
>>> not val
False
Khối
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>>
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Bạn có thể sử dụng cờ
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> val = "" # Truthiness value is `False`
>>> not val
True
>>> val = 5 # Truthiness value is `True`
>>> not val
False
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> val = "" # Truthiness value is `False`
>>> not val
True
>>> val = 5 # Truthiness value is `True`
>>> not val
False
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> val = "" # Truthiness value is `False`
>>> not val
True
>>> val = 5 # Truthiness value is `True`
>>> not val
False
Khối
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Điều duy nhất bạn cần làm để sử dụng khối >>> help("pass") The "pass" statement ******************** pass_stmt ::= "pass" "pass" is a null operation — when it is executed, nothing happens. It is useful as a placeholder when a statement is required syntactically, but no code needs to be executed, for example: def f(arg): pass # a function that does nothing (yet) class C: pass # a class with no methods (yet) 29 trong ví dụ này là xóa cờ >>> import keyword >>> keyword.kwlist ['False', 'None', 'True', 'and', 'as', 'assert', 'async', ... >>> len(keyword.kwlist) 35 28 và thay thế câu lệnh >>> help("keywords") Here is a list of the Python keywords. Enter any keyword to get more help. False class from or None continue global pass True def if raise and del import return as elif in try assert else is while async except lambda with await finally nonlocal yield break for not 74 cuối cùng bằng khối >>> help("pass") The "pass" statement ******************** pass_stmt ::= "pass" "pass" is a null operation — when it is executed, nothing happens. It is useful as a placeholder when a statement is required syntactically, but no code needs to be executed, for example: def f(arg): pass # a function that does nothing (yet) class C: pass # a class with no methods (yet) 29. Điều này cuối cùng tạo ra kết quả tương tự như ví dụ trước đây, chỉ với mã rõ ràng hơn.
Đôi khi sử dụng từ khóa
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Từ khóa cấu trúc: >>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
43, >>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
44, >>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
45, >>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
46, left if not left else right
1, >>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
48
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
left if not left else right
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Để xác định các chức năng và các lớp hoặc sử dụng các trình quản lý ngữ cảnh, bạn sẽ cần sử dụng một trong các từ khóa Python trong phần này. Họ là một phần thiết yếu của ngôn ngữ Python và sự hiểu biết khi nào nên sử dụng chúng sẽ giúp bạn trở thành một lập trình viên Python tốt hơn.
43 is used to define a function or method of a class. This is equivalent to >>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Từ khóa
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Từ khóa Python từ >>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
43 được sử dụng để xác định hàm hoặc phương thức của một lớp. Điều này tương đương với >>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
51 trong JavaScript và PHP. Cú pháp cơ bản để xác định chức năng với >>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
43 trông như thế này:
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Các chức năng và phương pháp có thể là các cấu trúc rất hữu ích trong bất kỳ chương trình Python nào. Để tìm hiểu thêm về việc xác định chúng và tất cả các trong và ngoài của chúng, hãy xem xác định chức năng Python của riêng bạn.
44 is as follows:>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Từ khóa
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Để xác định một lớp trong Python, bạn sử dụng từ khóa
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
9
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Các lớp là các công cụ mạnh mẽ trong lập trình hướng đối tượng và bạn nên biết về chúng và cách xác định chúng. Để tìm hiểu thêm, hãy xem chương trình hướng đối tượng (OOP) trong Python 3.
45 keyword:>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Từ khóa
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Các nhà quản lý bối cảnh là một cấu trúc thực sự hữu ích trong Python. Mỗi Trình quản lý bối cảnh thực hiện mã cụ thể trước và sau các câu lệnh bạn chỉ định. Để sử dụng một, bạn sử dụng từ khóa
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>>
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Sử dụng
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Nếu bạn muốn mở một tệp, hãy làm một cái gì đó với tệp đó và sau đó đảm bảo rằng tệp đã được đóng chính xác, sau đó bạn sẽ sử dụng trình quản lý ngữ cảnh. Hãy xem xét ví dụ này trong đó
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Trình quản lý bối cảnh I/O File được cung cấp bởi >>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
60 và được bắt đầu với từ khóa >>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
45 mở tệp để đọc, gán con trỏ tệp mở thành >>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
62, sau đó thực thi bất kỳ mã nào bạn chỉ định trong khối >>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
45. Sau đó, sau khi khối được thực thi, con trỏ tệp đóng. Ngay cả khi mã của bạn trong khối >>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
45 tăng ngoại lệ, con trỏ tệp vẫn sẽ đóng.
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Để biết ví dụ tuyệt vời về việc sử dụng
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Từ khóa
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Nếu bạn muốn truy cập vào kết quả của biểu thức hoặc trình quản lý ngữ cảnh được chuyển sang >>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
45, bạn sẽ cần phải bí danh bằng cách sử dụng >>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
46. Bạn cũng có thể đã thấy >>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
46 được sử dụng để nhập khẩu bí danh và ngoại lệ, và điều này không khác. Bí danh có sẵn trong khối >>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
45:
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Hầu hết thời gian, bạn sẽ thấy hai từ khóa Python này,
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
left if not left else right
left if not left else right
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Từ khóa
left if not left else right
Vì Python không có các chỉ số khối để chỉ định kết thúc của một khối, từ khóa left if not left else right
1 được sử dụng để chỉ định rằng khối bị bỏ trống một cách cố ý. Nó tương đương với không có hoạt động, hoặc không có hoạt động. Dưới đây là một vài ví dụ về việc sử dụng left if not left else right
1 để chỉ định rằng khối trống:
left if not left else right
left if not left else right
Để biết thêm về
left if not left else right
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Một ví dụ cơ bản về hàm
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Điều này tương đương với việc xác định chức năng với
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Một cách sử dụng phổ biến cho hàm
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Chức năng Lambda cung cấp một cách tốt đẹp để làm như vậy:
>>>
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Ví dụ này sắp xếp danh sách không dựa trên thứ tự bảng chữ cái mà theo thứ tự số của các ký tự cuối cùng của các chuỗi sau khi chuyển đổi chúng thành số nguyên. Không có
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Để so sánh, đây là những gì ví dụ trên sẽ trông như thế nào nếu không sử dụng
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>>
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Ví dụ này sắp xếp danh sách không dựa trên thứ tự bảng chữ cái mà theo thứ tự số của các ký tự cuối cùng của các chuỗi sau khi chuyển đổi chúng thành số nguyên. Không có
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Để so sánh, đây là những gì ví dụ trên sẽ trông như thế nào nếu không sử dụng
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Mã này tạo ra kết quả tương tự như ví dụ >>> import keyword >>> keyword.kwlist ['False', 'None', 'True', 'and', 'as', 'assert', 'async', ... >>> len(keyword.kwlist) 35 48, nhưng bạn cần xác định chức năng trước khi sử dụng.
Để biết thêm thông tin về
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Trả về từ khóa: >>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
43, >>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
94
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Có hai từ khóa Python được sử dụng để chỉ định những gì được trả về từ các chức năng hoặc phương thức:
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Từ khóa
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>>
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Ví dụ này sắp xếp danh sách không dựa trên thứ tự bảng chữ cái mà theo thứ tự số của các ký tự cuối cùng của các chuỗi sau khi chuyển đổi chúng thành số nguyên. Không có
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>>
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Ví dụ này sắp xếp danh sách không dựa trên thứ tự bảng chữ cái mà theo thứ tự số của các ký tự cuối cùng của các chuỗi sau khi chuyển đổi chúng thành số nguyên. Không có
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Để so sánh, đây là những gì ví dụ trên sẽ trông như thế nào nếu không sử dụng
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Mã này tạo ra kết quả tương tự như ví dụ
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Để biết thêm thông tin về >>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
48, hãy xem cách sử dụng các hàm Python Lambda.
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Trả về từ khóa:
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Có hai từ khóa Python được sử dụng để chỉ định những gì được trả về từ các chức năng hoặc phương thức:
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Từ khóa
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>>
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Ví dụ này sắp xếp danh sách không dựa trên thứ tự bảng chữ cái mà theo thứ tự số của các ký tự cuối cùng của các chuỗi sau khi chuyển đổi chúng thành số nguyên. Không có
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Để so sánh, đây là những gì ví dụ trên sẽ trông như thế nào nếu không sử dụng
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Mã này tạo ra kết quả tương tự như ví dụ >>> import keyword >>> keyword.kwlist ['False', 'None', 'True', 'and', 'as', 'assert', 'async', ... >>> len(keyword.kwlist) 35 48, nhưng bạn cần xác định chức năng trước khi sử dụng.
Để biết thêm thông tin về
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Trả về từ khóa:
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Từ khóa >>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
20
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Từ khóa Python từ
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Sau khi tuyên bố đó chạy,
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Ví dụ: nếu bạn muốn sử dụng lớp
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>>
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Nhập
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Từ khóa >>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
21
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Từ khóa
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Điều này sẽ nhập bất cứ thứ gì
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Nếu bạn muốn sử dụng
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>>
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Nhập
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Từ khóa >>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
21
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Từ khóa
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Điều này sẽ nhập bất cứ thứ gì
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Nếu bạn muốn sử dụng
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>>
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Nhập
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Từ khóa
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Từ khóa >>> x = True >>> x is True True >>> y = False >>> y is False True 21 được sử dụng cùng với >>> x = True >>> x is True True >>> y = False >>> y is False True 20 để nhập một cái gì đó cụ thể từ một mô -đun:
Điều này sẽ nhập bất cứ thứ gì
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Nếu bạn muốn sử dụng
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Nhập >>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
26 như thế này làm cho lớp >>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
26 có sẵn, nhưng không có gì khác từ mô -đun >>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
27 có sẵn. >>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
26 hiện có sẵn mà không cần bạn phải tham khảo nó từ mô -đun >>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
27.
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Từ khóa
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Từ khóa
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Đối với các mô -đun có tên thực sự dài hoặc bí danh nhập khẩu thường được sử dụng,
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
Nếu bạn muốn nhập lớp
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
Bây giờ
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
Đây là một giải pháp thay thế tốt hơn để chỉ nhập mọi thứ từ một mô -đun và nó cho phép bạn rút ngắn tên của mô -đun đang được nhập.
Từ khóa xử lý ngoại lệ: >>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
57, >>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
58, >>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
59, >>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
60, >>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
29, >>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
62
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Một trong những khía cạnh phổ biến nhất của bất kỳ chương trình Python nào là việc nâng cao và bắt các trường hợp ngoại lệ. Bởi vì đây là một khía cạnh cơ bản của tất cả các mã Python, có một số từ khóa Python có sẵn để giúp làm cho phần này của mã của bạn rõ ràng và súc tích.
58 keyword is used with >>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
Các phần dưới đây đi qua các từ khóa Python này và cách sử dụng cơ bản của chúng. Đối với một hướng dẫn chuyên sâu hơn về các từ khóa này, hãy xem các ngoại lệ của Python: Giới thiệu.
>>>
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
Bạn có thể sửa đổi
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
Tại đây, bạn sửa đổi
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Lưu ý rằng từ khóa
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Mặc dù nó được phép về mặt cú pháp, nhưng hãy cố gắng không sử dụng các câu lệnh
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
Nếu bạn thực sự muốn bắt một loạt các ngoại lệ, thì hãy chỉ định cha mẹ
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
Từ khóa >>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
59
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Từ khóa
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Bạn đã sử dụng
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Từ khóa >>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
60
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Từ khóa Python từ
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
Sử dụng ví dụ từ trước, có thể hữu ích để chỉ định rằng, bất kể điều gì xảy ra, bạn muốn biết những đối số nào chức năng được gọi với. Bạn có thể sửa đổi
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
Bây giờ, cho dù
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>>
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
Từ khóa
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Từ khóa >>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
29 được sử dụng với >>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
57 và >>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
58
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Bạn đã học được rằng từ khóa
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> help("keywords")
Here is a list of the Python keywords. Enter any keyword to get more help.
False class from or
None continue global pass
True def if raise
and del import return
as elif in try
assert else is while
async except lambda with
await finally nonlocal yield
break for not
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
Trong bối cảnh này, mã trong khối
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
Trong ví dụ
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> x = "this is a truthy value"
>>> if x is True: # Don't do this
... print("x is True")
...
>>> if x: # Do this
... print("x is truthy")
...
x is truthy
Bây giờ kết quả của một cuộc gọi đến
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
Để biết thêm về việc sử dụng khối
>>> help("pass")
The "pass" statement
********************
pass_stmt ::= "pass"
"pass" is a null operation — when it is executed, nothing happens. It
is useful as a placeholder when a statement is required syntactically,
but no code needs to be executed, for example:
def f(arg): pass # a function that does nothing (yet)
class C: pass # a class with no methods (yet)
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Từ khóa >>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
62
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Từ khóa
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Nói chung, các câu lệnh
>>> x = True
>>> x is True
True
>>> y = False
>>> y is False
True
Từ khóa lập trình không đồng bộ: >>> def func(): ... print("hello") ... >>> x = func() hello >>> print(x) None 6, >>> def func(): ... print("hello") ... >>> x = func() hello >>> print(x) None 5
Lập trình không đồng bộ là một chủ đề phức tạp. Có hai từ khóa Python được xác định để giúp làm cho mã không đồng bộ trở nên dễ đọc hơn và sạch hơn:
>>> def func():
... print("hello")
...
>>> x = func()
hello
>>> print(x)
None
>>> def func():
... print("hello")
...
>>> x = func()
hello
>>> print(x)
None
Các phần dưới đây giới thiệu hai từ khóa không đồng bộ và cú pháp cơ bản của chúng, nhưng họ đã giành được chiều sâu về lập trình không đồng bộ. Để tìm hiểu thêm về lập trình không đồng bộ, hãy xem Async IO trong Python: một hướng dẫn hoàn chỉnh và bắt đầu với các tính năng Async trong Python.
Từ khóa >>> def func():
... print("hello")
...
>>> x = func()
hello
>>> print(x)
None
6
>>> def func():
... print("hello")
...
>>> x = func()
hello
>>> print(x)
None
Từ khóa
>>> def func():
... print("hello")
...
>>> x = func()
hello
>>> print(x)
None
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> def func():
... print("hello")
...
>>> x = func()
hello
>>> print(x)
None
>>> def func():
... print("hello")
...
>>> x = func()
hello
>>> print(x)
None
>>> import keyword
>>> keyword.kwlist
['False', 'None', 'True', 'and', 'as', 'assert', 'async', ...
>>> len(keyword.kwlist)
35
>>> def func():
... print("hello")
...
>>> x = func()
hello
>>> print(x)
None
>>> x = "this is a truthy value"
>>> if x is True: # Don't do this
... print("x is True")
...
>>> if x: # Do this
... print("x is truthy")
...
x is truthy
Bạn có thể tạo một chức năng không đồng bộ bằng cách thêm từ khóa
>>> def func():
... print("hello")
...
>>> x = func()
hello
>>> print(x)
None
Từ khóa >>> def func():
... print("hello")
...
>>> x = func()
hello
>>> print(x)
None
5
>>> def func():
... print("hello")
...
>>> x = func()
hello
>>> print(x)
None
Từ khóa Python từ ____ ____75 được sử dụng trong các chức năng không đồng bộ để chỉ định một điểm trong hàm nơi điều khiển được đưa trở lại vòng lặp sự kiện để các chức năng khác chạy. Bạn có thể sử dụng nó bằng cách đặt từ khóa
>>> def func():
... print("hello")
...
>>> x = func()
hello
>>> print(x)
None
>>> def func():
... print("hello")
...
>>> x = func()
hello
>>> print(x)
None
>>> def func():
... print("hello")
...
>>> x = func()
hello
>>> print(x)
None
>>> def func():
... print("hello")
...
>>> x = func()
hello
>>> print(x)
None
>>> def func():
... print("hello")
...
>>> x = func()
hello
>>> print(x)
None
>>> x = "this is a truthy value"
>>> if x is True: # Don't do this
... print("x is True")
...
>>> if x: # Do this
... print("x is truthy")
...
x is truthy
Khi sử dụng
>>> def func():
... print("hello")
...
>>> x = func()
hello
>>> print(x)
None
Từ khóa xử lý biến: >>> x = "this is a truthy value" >>> x is True False >>> bool(x) is True True >>> y = "" # This is falsy >>> y is False False >>> bool(y) is False True 66, >>> x = "this is a truthy value" >>> x is True False >>> bool(x) is True True >>> y = "" # This is falsy >>> y is False False >>> bool(y) is False True 67, >>> x = "this is a truthy value" >>> x is True False >>> bool(x) is True True >>> y = "" # This is falsy >>> y is False False >>> bool(y) is False True 68
Ba từ khóa Python được sử dụng để làm việc với các biến. Từ khóa
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
Từ khóa >>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
66
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
66 được sử dụng trong Python để không đặt một biến hoặc tên. Bạn có thể sử dụng nó trên các tên biến, nhưng sử dụng phổ biến hơn là xóa các chỉ mục khỏi danh sách hoặc từ điển. Để giải quyết một biến, hãy sử dụng >>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
66 theo sau là biến bạn muốn giải quyết: is used in Python to unset a variable or name. You can use it on variable names, but a more common use is to remove indexes from a list or dictionary. To unset a variable, use >>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
Hãy giả sử bạn muốn làm sạch một từ điển mà bạn nhận được từ một phản hồi API bằng cách ném ra các phím mà bạn biết bạn đã giành được sử dụng. Bạn có thể làm như vậy với từ khóa
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
>>>
>>> x = "this is a truthy value"
>>> if x is True: # Don't do this
... print("x is True")
...
>>> if x: # Do this
... print("x is truthy")
...
x is truthy
Điều này sẽ loại bỏ các khóa
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
Từ khóa >>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
67
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
Nếu bạn cần sửa đổi một biến được xác định trong một hàm nhưng được xác định trong phạm vi toàn cầu, thì bạn sẽ cần sử dụng từ khóa
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
Một ví dụ cơ bản là tăng một biến toàn cầu với một cuộc gọi chức năng. Bạn có thể làm điều đó với từ khóa
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
>>>
>>> x = "this is a truthy value"
>>> if x is True: # Don't do this
... print("x is True")
...
>>> if x: # Do this
... print("x is truthy")
...
x is truthy
Điều này sẽ loại bỏ các khóa
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
Từ khóa >>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
67
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
Nếu bạn cần sửa đổi một biến được xác định trong một hàm nhưng được xác định trong phạm vi toàn cầu, thì bạn sẽ cần sử dụng từ khóa
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
Một ví dụ cơ bản là tăng một biến toàn cầu với một cuộc gọi chức năng. Bạn có thể làm điều đó với từ khóa
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
Điều này thường không được coi là thực hành tốt, nhưng nó có cách sử dụng của nó. Để tìm hiểu thêm về từ khóa >>> x = "this is a truthy value" >>> x is True False >>> bool(x) is True True >>> y = "" # This is falsy >>> y is False False >>> bool(y) is False True 67, hãy xem Python Phạm vi & Quy tắc LegB: Giải quyết tên trong mã của bạn.
Từ khóa
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
Từ khóa >>> x = "this is a truthy value" >>> x is True False >>> bool(x) is True True >>> y = "" # This is falsy >>> y is False False >>> bool(y) is False True 68 tương tự như >>> x = "this is a truthy value" >>> x is True False >>> bool(x) is True True >>> y = "" # This is falsy >>> y is False False >>> bool(y) is False True 67 ở chỗ nó cho phép bạn sửa đổi các biến từ một phạm vi khác. Với >>> x = "this is a truthy value" >>> x is True False >>> bool(x) is True True >>> y = "" # This is falsy >>> y is False False >>> bool(y) is False True 67, phạm vi mà bạn đã lấy từ là phạm vi toàn cầu. Với >>> x = "this is a truthy value" >>> x is True False >>> bool(x) is True True >>> y = "" # This is falsy >>> y is False False >>> bool(y) is False True 68, phạm vi mà bạn kéo từ là phạm vi cha mẹ. Cú pháp tương tự như >>> x = "this is a truthy value" >>> x is True False >>> bool(x) is True True >>> y = "" # This is falsy >>> y is False False >>> bool(y) is False True 67:
Từ khóa này được sử dụng rất thường xuyên, nhưng đôi khi nó có thể tiện dụng. Để biết thêm về phạm vi và từ khóa
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
>>> def func():
... print("hello")
...
>>> x = func()
hello
>>> print(x)
None
Từ khóa Python không dùng nữa
Đôi khi một từ khóa Python trở thành một hàm tích hợp. Đó là trường hợp với cả
>>> def func():
... print("hello")
...
>>> x = func()
hello
>>> print(x)
None
>>> def func():
... print("hello")
...
>>> x = func()
hello
>>> print(x)
None
Từ khóa
>>> def func():
... print("hello")
...
>>> x = func()
hello
>>> print(x)
None
Khi >>> def func(): ... print("hello") ... >>> x = func() hello >>> print(x) None 7 là một từ khóa, cú pháp để in một cái gì đó lên màn hình trông như thế này:
Lưu ý rằng nó trông giống như rất nhiều câu lệnh từ khóa khác, với từ khóa theo sau là các đối số.
8 keyword took Python code as a string and executed it. This was done with the following syntax: >>> def func():
... print("hello")
...
>>> x = func()
hello
>>> print(x)
None
Bây giờ
>>> def func():
... print("hello")
...
>>> x = func()
hello
>>> print(x)
None
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
>>>
>>> x = "this is a truthy value"
>>> if x is True: # Don't do this
... print("x is True")
...
>>> if x: # Do this
... print("x is truthy")
...
x is truthy
Điều này sẽ loại bỏ các khóa
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
Từ khóa >>> x = "this is a truthy value" >>> x is True False >>> bool(x) is True True >>> y = "" # This is falsy >>> y is False False >>> bool(y) is False True 67
Nếu bạn cần sửa đổi một biến được xác định trong một hàm nhưng được xác định trong phạm vi toàn cầu, thì bạn sẽ cần sử dụng từ khóa
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
Một ví dụ cơ bản là tăng một biến toàn cầu với một cuộc gọi chức năng. Bạn có thể làm điều đó với từ khóa
>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
Điều này thường không được coi là thực hành tốt, nhưng nó có cách sử dụng của nó. Để tìm hiểu thêm về từ khóa
67, hãy xem Python Phạm vi & Quy tắc LegB: Giải quyết tên trong mã của bạn.>>> x = "this is a truthy value"
>>> x is True
False
>>> bool(x) is True
True
>>> y = "" # This is falsy
>>> y is False
False
>>> bool(y) is False
True
- Từ khóa
68Python keywords in version 3.8 and their basic usage>>> x = "this is a truthy value" >>> x is True False >>> bool(x) is True True >>> y = "" # This is falsy >>> y is False False >>> bool(y) is False True - Từ khóa
68 tương tự như>>> x = "this is a truthy value" >>> x is True False >>> bool(x) is True True >>> y = "" # This is falsy >>> y is False False >>> bool(y) is False True
67 ở chỗ nó cho phép bạn sửa đổi các biến từ một phạm vi khác. Với>>> x = "this is a truthy value" >>> x is True False >>> bool(x) is True True >>> y = "" # This is falsy >>> y is False False >>> bool(y) is False True
67, phạm vi mà bạn đã lấy từ là phạm vi toàn cầu. Với>>> x = "this is a truthy value" >>> x is True False >>> bool(x) is True True >>> y = "" # This is falsy >>> y is False False >>> bool(y) is False True
68, phạm vi mà bạn kéo từ là phạm vi cha mẹ. Cú pháp tương tự như>>> x = "this is a truthy value" >>> x is True False >>> bool(x) is True True >>> y = "" # This is falsy >>> y is False False >>> bool(y) is False True
67:resources to help deepen your understanding of many of the keywords>>> x = "this is a truthy value" >>> x is True False >>> bool(x) is True True >>> y = "" # This is falsy >>> y is False False >>> bool(y) is False True - Từ khóa này được sử dụng rất thường xuyên, nhưng đôi khi nó có thể tiện dụng. Để biết thêm về phạm vi và từ khóa
68, hãy xem phạm vi Python & Quy tắc LegB: Giải quyết tên trong mã của bạn.>>> x = "this is a truthy value" >>> x is True False >>> bool(x) is True True >>> y = "" # This is falsy >>> y is False False >>> bool(y) is False True
2 module to work with keywords in a programmatic way>>> def func(): ... print("hello") ... >>> x = func() hello >>> print(x) None
Từ khóa Python không dùng nữa
Xem bây giờ hướng dẫn này có một khóa học video liên quan được tạo bởi nhóm Python thực sự.Xem cùng với hướng dẫn bằng văn bản để hiểu sâu hơn về sự hiểu biết của bạn: Khám phá các từ khóa trong Python This tutorial has a related video course created by the Real Python team. Watch it together with the written tutorial to deepen your understanding: Exploring Keywords in Python
