[Python-ideas] List Comprehensions

[Chris Angelico]

On Tue, Feb 9, 2016 at 10:54 AM, Michael Selik <mike at selik.org> wrote:
> I could imagine a module of fancy iterables overloading __and__ for that
> purpose, but it ought to be a large enough chunk of functionality to warrant
> a mini-language. Like NumPy. As much as I dislike the term "domain-specific
> language", I think this example of overloading operators falls into that
> category. One could take the itertools module and map all sorts of operators
> to its features:
>
>     a & b       ==>     chain(a, b)
>     it[j:k]     ==>     islice(it, j, k)
>     +it         ==>     tee(it)
>     a * b       ==>     product(a, b)
>     2-it        ==>     pairwise(it)
>
> etc. Not saying it's a good idea for the standard library, but I could see a
> module that makes extensive use of itertools doing so. It's worth repeating
> that I prefer using the word instead of the operator for most if not all of
> these cases.

And the cool part of it is that anyone can do this simply by creating
a class called "iter", and using that everywhere. A simple "from magic
import iter" will enable this for the people who want it AND make it
possible for everyone else to figure out what's going on.

Personally, I don't use the itertools functions anywhere near enough
to justify magic syntax, but there are people who do.

ChrisA