On 2018-06-05 01:25, Steven D'Aprano wrote:
On Mon, Jun 04, 2018 at 02:22:29PM -0700, Ben Rudiak-Gould wrote:
I'd like to propose adding `append` and `extend` methods to dicts
which behave like `__setitem__` and `update` respectively, except that
they raise an exception (KeyError?) instead of overwriting preexisting
entries.
Very often I expect that the key I'm adding to a dict isn't already in
it.
[snip]
If I want to verify that, I have to expand my single-line
assignment statement to 3-5 lines (depending on whether the dict and
key are expressions that I now need to assign to local variables).
I'm sorry, I can't visualise how it would take you up to five lines to
check and update a key. It shouldn't take more than two:
if key not in d:
d[key] = value
It shouldn't take more than one:
d.setdefault(key, value)
:-)
[snip]
_______________________________________________
Python-ideas mailing list
Python-ideas@python.org
https://mail.python.org/mailman/listinfo/python-ideas
Code of Conduct: http://python.org/psf/codeofconduct/
