I tried this code:
names = ['Adam', 'Bob', 'Cyril']
text = f"Winners are:\n{'\n'.join(names)}"
print(text)
However, '\'
cannot be used inside the {...}
expression portions of an f-string. How can I make it work? The result should be:
Winners are:
Adam
Bob
Cyril
See Why isn't it possible to use backslashes inside the braces of f-strings? How can I work around the problem? for some additional discussion of why the limitation exists.
You can use backslashes within f-strings and the existing code from the question works as expected. See https://docs.python.org/3.12/whatsnew/3.12.html#pep-701-syntactic-formalization-of-f-strings.
You can't. Backslashes cannot appear inside the curly braces {}
; doing so results in a SyntaxError
:
>>> f'{\}'
SyntaxError: f-string expression part cannot include a backslash
This is specified in the PEP for f-strings:
Backslashes may not appear inside the expression portions of f-strings, [...]
One option is assigning '\n'
to a name and then .join
on that inside the f
-string; that is, without using a literal:
names = ['Adam', 'Bob', 'Cyril']
nl = '\n'
text = f"Winners are:{nl}{nl.join(names)}"
print(text)
Results in:
Winners are:
Adam
Bob
Cyril
Another option, as specified by @wim, is to use chr(10)
to get \n
returned and then join there. f"Winners are:\n{chr(10).join(names)}"
Yet another, of course, is to '\n'.join
beforehand and then add the name accordingly:
n = "\n".join(names)
text = f"Winners are:\n{n}"
which results in the same output.
This is one of the small differences between f
-strings and str.format
. In the latter, you can always use punctuation granted that a corresponding wacky dict is unpacked that contains those keys:
>>> "{\\} {*}".format(**{"\\": 'Hello', "*": 'World!'})
"Hello World!"
(Please don't do this.)
In the former, punctuation isn't allowed because you can't have identifiers that use them.
Aside: I would definitely opt for print
or format
, as the other answers suggest as an alternative. The options I've given only apply if you must for some reason use f-strings.
Just because something is new, doesn't mean you should try and do everything with it ;-)