empty arguments

[micseydel]

I'm not against increasing the performance of code when it makes sense. But I suspect a decorator is a better solution than a hack with default arguments.

[volcano63]

I'm not against increasing the performance of code when it makes sense. But I suspect a decorator is a better solution than a hack with default arguments.

You would be very surprised, but the hack in question was implemented in the internal function of 2-layered decorator. Decorated functions had to be able to share cache - that why I couldn't use closure. And class decorator did not work for some reason - I don't remember why.

I am not overfond of hacks - they may be a major pain in the ass, especially when those are not documented (I've seen one or two, well - some people strive for job security ). That's why my function had more line of comments than lines of actual code.

On the other hand - if BDFL in his "for-life" wisdom made that loophole in the language, probably he saw a reason for that.

[nilamo]

When I've wanted caching, I just used a decorator. Using something that might be an implementation detail feels susfishous to me.
Do lists in function arguments work that way in other versions of python, like pypy or ironpython? I don't have anything but cpython installed at work to test it.

[volcano63]

When I've wanted caching, I just used a decorator.  Using something that might be an implementation detail feels susfishous to me.
Do lists in function arguments work that way in other versions of python, like pypy or ironpython?  I don't have anything but cpython installed at work to test it.

I don't know, there are some think like system limitations? Compensation for design deficiencies?! If every problem could have been solved by trivial methods .....

[micseydel]

I can't cite anything, but I'm fairly certain that it's a language spec and not an implementation detail, so unless you find evidence that it really is implementation-specific I wouldn't cite that as a reason.

[volcano63]

Can we stop the pissing content ? Just curious....

[micseydel]

Do you mean pissing contest? I don't see that here, though I didn't realize we got off topic. If people want to continue the discussion about mutable default arguments being a hack or not, that should probably be a separate thread.