Hướng dẫn multi-line statement in python

Python statements are the code instructions that are executed by the Python interpreter. Python executes statements one by one as they appear in the code.

Let’s look at some simple statement examples.

count = 10  # statement 1

class Foo:  # statement 2
    pass    # statement 3

Python Multi-line Statements

Python statements are usually written in a single line. The newline character marks the end of the statement. If the statement is very long, we can explicitly divide it into multiple lines with the line continuation character [\].

Let’s look at some examples of multi-line statements.

message = "Hello There.\nYou have come to the right place to learn Python Programming.\n" \
          "Follow the tutorials to become expert in Python. " \
          "Don't forget to share it with your friends too."

math_result = 1 + 2 + 3 + 4 + \
              5 + 6 + 7 + 8 + \
              9 + 10

print[message]
print[math_result]

Python supports multi-line continuation inside parentheses [ ], brackets [ ], and braces { }. The brackets are used by List and the braces are used by dictionary objects. We can use parentheses for expressions, tuples, and strings.

message = ["Hello\n"
           "Hi\n"
           "Namaste"]

math_result = [1 + 2 + 3 + 4 +
               5 + 6 + 7 + 8 +
               9 + 10]

prime_numbers_tuple = [2, 3, 5, 7,
                       11, 13, 17]

list_fruits = ["Apple", "Banana",
               "Orange", "Mango"]

dict_countries = {"USA": "United States of America", "IN": "India",
                  "UK": "United Kingdom", "FR": "France"}

Can we have multiple statements in a single line?

We can use a semicolon [;] to have multiple statements in a single line.

Python Simple Statements

Python simple statement is comprised of a single line. The multiline statements created above are also simple statements because they can be written in a single line. Let’s look at some important types of simple statements in Python.

1. Python Expression Statement

i = int["10"]  # expression is evaluated and the result is assigned to the variable.

sum = 1 + 2 + 3  # statement contains an expression to be evaluated first.

2. Python Assignment Statement

count = 10  # value is assigned to the variable, no expression is evaluated

message = "Hi"

3. Python Assert Statement

assert 5 < 10
assert [True or False]

Read more at Python assertions.

4. Python pass Statement

def foo[]:
    pass  # pass statement

Read more at pass statement in Python.

5. Python del Statement

name = "Python"
del name  # del statement

6. Python return Statement

def foo[]:
    return 10  # return statement

Recommended Read: return statement in Python.

7. Python yield Statement

def yield_statement[]:
    yield 'Statement 1'  # yield statement

Read more at yield in Python.

8. Python raise Statement

def raise_example[]:
    raise TypeError['Exception Example']  # raise statement

Read more about exception handling in Python.

9. Python break Statement

numbers = [1, 2, 3]


for num in numbers:
    if num > 2:
        break  # break statement

Read more at Python break statement.

10. Python continue Statement

numbers = [1, 2, 3]


for num in numbers:
    if num > 2:
        continue  # continue statement
    print[num]

Further Reading: Python continue statement

11. Python import Statement

import collections
import calendar as cal
from csv import DictReader

Recommended Read: import in Python.

12. Python global Statement

name = "Python"


def global_example[]:
    global name  # global statement
    name = "Flask"


print[name]  # prints Python
global_example[]
print[name]  # prints Flask

13. Python nonlocal Statement

def outer_function[]:
    scope = "local"

    def inner_function[]:
        nonlocal scope  # nonlocal statement
        scope = "nonlocal"
        print[scope]

    inner_function[]
    print[scope]


outer_function[]

Python Compound Statements

Python compound statements contain a group of other statements and affect their execution. The compound statement generally spans multiple lines. Let’s briefly look into a few compound statements.

1. Python if Statement

if 5 < 10:
    print["This will always print"]
else:
    print["Unreachable Code"]

Recommended Read: Python if-else statement

2. Python for Statement

for n in [1, 2, 3]:
    print[n]

Further Reading: Python for loop

3. Python while Statement

count = 5
while count > 0:
    print[count]
    count -= 1

Read more at Python while loop.

4. Python try Statement

try:
    print["try"]
except ValueError as ve:
    print[ve]

5. Python with Statement

with open['data.csv'] as file:
    file.read[]

6. Python Function Definition Statement

A python function definition is an executable statement. Its execution binds the function name in the current local namespace to a function object. The function is executed only when it’s called.

7. Python Class Definition Statement

It’s an executable statement. Python class definition defines the class object.

8. Python Coroutines Function Definition Statement

import asyncio

async def ping[url]:
    print[f'Ping Started for {url}']
    await asyncio.sleep[1]
    print[f'Ping Finished for {url}']

Summary

Python statements are used by the Python interpreter to run the code. It’s good to know about the different types of statements in Python.

References:

• Simple Statements
• Compound Statements