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Python f-strings can do more than you thought

Envoy-VC
・2 min read

In this Article I'm going to be talking about f-strings and some of the cool things that you can do with them. so most of you are probably already aware of what f strings are.

🎯 f-strings

Also called “formatted string literals,” f-strings are string literals that have an f at the beginning and curly braces containing expressions that will be replaced with their values.

1.Put a '=' Sign afterwards

One of the really cool things that you can do is just put an equals sign afterwards,eg-

Code -

word = 'Hello World'
num = 152
print(f'The value of word is f{word}')
print(f'{word=}')

print(f'The value of num is f{num}')
print(f'{num=}')
print(f'{num + 8 =}')
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Output -

The value of word is Hello World
word='Hello World'
The value of num is f152
num=152
num + 8 =160
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2.Conversions

So if you're not aware,  inside the curly braces of an f string after the expression you can put a ```!a ,!s , !r ``` , and  what these do is instead of printing the value of this thing, it will additionally do some extra thing on top of that.

!r - repr() 'The repr() method returns a string containing a printable representation of an object.'

!a - ascii 'all the non ascii characters get replaced with an ascii safe escaped version of it'

!s - string conversion operator 'formating'

Code -

def conversion():
    str_value = "Hello World 😀"
    print(f'{str_value!r}')
    print(f'{str_value!a}')
    print(f'{str_value!s}')

conversion()

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Output -

'Hello World 😀'
'Hello World \U0001f600'
Hello World 😀
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3.Formatting

':' after the variable

Code -

import datetime

def formatting():
    num_value = 475.2486
    now = datetime.datetime.utcnow()

    #Formats the datee in the given format
    print(f'{now=:%Y-%m-%d}')

    # Rounds the decimal to 2 digits
    print(f'{num_value:.2f}')

formatting()
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Output -

now=2021-08-04
475.25
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Discussion (2)

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zeromomentum profile image
Suhas

If you use {Number:,} you can automatically add delimiters to the number

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waylonwalker profile image
Waylon Walker

f strings are simply amazing