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0 pointsodonnellryan12y ago0 comments

Unpacking pretty much does one thing, and it makes that one thing easier and a lot more readable. Combine that with list comprehension (from what I understand C#'s LINQ is similar) and you end up with code that's highly maintainable/readable (as long as you name your variables appropriately, of course).

I believe Python supports pattern matching other than Regex as well.

0 comments

mercurial12y ago

Python list comprehensions are not lazy, though. If you generate [for x in xrange(1, 10000)] you'll get 10000 elements in your list. My understanding is that LINQ list comprehensions are that.

> I believe Python supports pattern matching other than Regex as well.

That's pattern matching on strings. The kind of pattern matching being discussed here is pattern matching on data types (see [1]).

1: http://en.wikipedia.org/wiki/Pattern_matching

rnnr12y ago

Python does have generator expressions, for instance what you wrote above is written (lazily) as:(x for x in xrange(1, 10000))

It doesnt have functional style pattern matching though.

whyever12y ago

'Lazy lists' are called generators in Python. Just use (...) Instead of [...] in your example.

mercurial12y ago

I'm aware of generator expressions, but the fact that list comprehensions are not lazy can trip people if they are used to other languages with this feature, since they are usually lazy.

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0 pointsodonnellryan12y ago0 comments

I believe Python supports pattern matching other than Regex as well.

0 comments

mercurial12y ago

Python list comprehensions are not lazy, though. If you generate [for x in xrange(1, 10000)] you'll get 10000 elements in your list. My understanding is that LINQ list comprehensions are that.

> I believe Python supports pattern matching other than Regex as well.

That's pattern matching on strings. The kind of pattern matching being discussed here is pattern matching on data types (see [1]).

1: http://en.wikipedia.org/wiki/Pattern_matching

rnnr12y ago

Python does have generator expressions, for instance what you wrote above is written (lazily) as:(x for x in xrange(1, 10000))

It doesnt have functional style pattern matching though.

whyever12y ago

'Lazy lists' are called generators in Python. Just use (...) Instead of [...] in your example.

mercurial12y ago

I'm aware of generator expressions, but the fact that list comprehensions are not lazy can trip people if they are used to other languages with this feature, since they are usually lazy.

2 more replies

j / k navigate · click thread line to collapse