Why no warnings when re-assigning builtin names?

Chris Angelico rosuav at gmail.com
Wed Aug 17 20:02:23 CEST 2011


On Wed, Aug 17, 2011 at 6:38 PM, Seebs <usenet-nospam at seebs.net> wrote:
> I may have been unclear about jumping topics; that comment was about
> monkey-patching, not about shadowing.
>

Ah, apologies.

Monkey-patching is a way of using the middle of a stack of code
without using what's below it. If everything is statically linked,
then every function does exactly what it was written to do and no
more; if it accepts a file object as an argument, you could give it
some other file-like object, but that's all. However, if the function
was written to use print() and you don't want it to print to the
screen, what do you do? Obviously it's your responsibility to ensure
that your replacement is 100% equivalent in the required
functionality, but it's a great flexibility to simply change the
meaning of "print"; the alternative is to copy and paste the code,
make one change (or even no change at all, if your replacement print()
is a global), and run that.

As Ethan posted while I was typing this, you're allowed to do it, but
you just need to have a good reason for it. I like to explain/justify
myself in comments when these things crop up in my code.

ChrisA



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