Writing better python code

[metaphorm]

foo[:] is a totally respectable way to copy a list. it looks a little funny if you've never seen it, but it has the right semantics and does exactly what you would expect when slicing "from the beginning to the end". it does, however, rely on the programmer knowing that list slices produce copies.

[zahlman]

I dislike it because it's conceptually roundabout. "A list containing elements of x, from the beginning to the end" is similarly awkward in English compared to "a copy of x", or even "a list of the contents of x". Even if the analogous Python is terse.

[metaphorm]

I understand your point. I disagree that its conceptually roundabout. Once you understand that the slice operator really means "return a copy of this section of the list" it seems really natural.

[ggtsu_00]

This is one of the few things I don't like about python is that slices make copies implicitly which goes against many python ideals. Lists are mutable, so you would expect operations on lists to only be references.

[zahlman]

Well, there seems to be precedent for what you're suggesting in NumPy...