Single liner to add text to filename before extension with f-strings

Question

I want to add some text to a file name before the extension. Example: name.ext >>> name_su.ext.
I can do it with traditional python string formatting:

filename = 'name.ext'
suffix = '_su'
print("{0}{2}{1}".format(*os.path.splitext(filename) + (suffix, )))
# This will print: name_su.ext

I wonder if I can achieve the same with f-string notation, in a single line, without calling os.path.splitext(filename) twice.

FWIW, you don't even need interpolation for this. `suffix.join(os.path.splitext(filename))` — wjandrea, Jun 21 '20 at 18:44
Take a look at [this](https://stackoverflow.com/questions/42756537/f-string-syntax-for-unpacking-a-list-with-brace-suppression) question. — Diptangsu Goswami, Jun 21 '20 at 18:50
@wjandrea, thanks A LOT for this advice. It's quite obvious but I never would have thought about it, and I used it today for this same purpose. — Raúl Núñez de Arenas Coronado, Feb 22 '22 at 09:06

score 0 · Answer 1 · answered Jun 21 '20 at 18:49

0

Calling os.path.splitext() twice might be avoidable, but it's fast and readable:

print(f'{os.path.splitext(filename)[0] + suffix + os.path.splitext(filename)[1]}')

answered Jun 21 '20 at 18:49

AlexM

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Thank you, @AlexM. I was looking for a way to do it without calling twice `os.path.splitext()`. – Marcos Jun 21 '20 at 19:16
Why even bother with an f-string? `print(os.path.splitext(filename)[0] + suffix + os.path.splitext(filename)[1])` – wjandrea Jun 22 '20 at 15:10
Also, there's no need to call it twice, like I commented on the question: `suffix.join(os.path.splitext(filename))`. So if you needed an f-string, `print(f'{suffix.join(os.path.splitext(filename))}')` – wjandrea Jun 22 '20 at 15:15

Single liner to add text to filename before extension with f-strings

1 Answers1