Is there an idiomatic way to add an extension using Python's Pathlib?

Question

I'm using Python's Pathlib and I want to take something like

p = Path('/path/to/foo') 

And then try a couple of different extensions. I can do

for ext in ['.txt', '.md', '.note']     filename = Path(str(p) + ext) 

but that feels a little awkward. Is there a better way to do this?

Answer 1

The with_suffix method will return a new path with a different extension, either changing an existing extension or adding a new one. Examples from the docs:

>>> p = PureWindowsPath('c:/Downloads/pathlib.tar.gz') >>> p.with_suffix('.bz2') PureWindowsPath('c:/Downloads/pathlib.tar.bz2') >>> p = PureWindowsPath('README') >>> p.with_suffix('.txt') PureWindowsPath('README.txt') 

In your case, p.with_suffix(ext) would do the job.

For cases where you need to add a suffix after any existing suffixes instead of removing existing suffixes, you can use p.with_suffix(p.suffix+ext). This is kind of clunky, though, and I don't know whether I would prefer it over Path(str(p)+ext).

Answer 2

You might use pathlib3x - it offers a backport of the latest (at the date of writing this answer Python 3.10.a0) Python pathlib for Python 3.6 or newer, and a few additional functions like append_suffix

>>> python -m pip install pathlib3x  >>> import pathlib3x as pathlib  >>> pathlib.Path('some_path').append_suffix('.ext') PosixPath('some_path.ext')  >>> pathlib.Path('some_path.ext.ext2').append_suffix('.ext3') PosixPath('some_path.ext.ext2.ext3')  >>> pathlib.Path('some_path.ext').append_suffix('.tar.gz') PosixPath('some_path.ext.tar.gz')   

you can find it on github or PyPi

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^{Disclaimer: I'm the author of the pathlib3x library.}