In Python format (f-string) strings, what does !r mean?

python python-3.6 f-string
nk abram picture nk abram · Jun 28, 2017 · Viewed 7.4k times · Source

I get what the new f strings in python 3.6 do, but what about the ending !r as found in the code snip below. 

def __repr__(self):
    return (f'Pizza({self.radius!r}, 'f'{self.ingredients!r})')

Answer

Dimitris Fasarakis Hilliard picture Dimitris Fasarakis Hilliard · Jun 28, 2017

It just calls the repr of the value supplied.

It's usage is generally not really needed with f-strings since with them you can just do repr(self.radius) which is arguably more clear in its intent.

!r (repr), !s (str) and !a (ascii) were kept around just to ease compatibility with the str.format alternative, you don't need to use them with f-strings.

Related questions

How to use newline '\n' in f-string to format output in Python 3.6?

I would like to know how to format this case in a Pythonic way with f-strings: names = ['Adam', 'Bob', 'Cyril'] text = f"Winners are:\n{'\n'.join(names)}" print(text) The problem is that '\' cannot be used …

Read More
How to escape f-strings in python 3.6?

I have a string in which I would like curly-brackets, but also take advantage of the f-strings feature. Is there some syntax that works for this? Here are two ways it does not work. I would like to include the …

Read More
Multiline f-string in Python

I'm trying to write PEP-8 compliant code for a domestic project (I must admit that those are my first steps in the python world) and i've got a f-string that is more than 80 char long - the solid thin line …

Read More