Earlier on the thread, I made a similar point that it would be nice to have a way to filter without the redundant for x in x. Though I can’t think of a really good way to express it. But as for filtered for loops:
"for thing in (x for x in collection if is_interesting(x))"
It's pretty important that comprehensions can express transformations (i.e. map) along with filters. A lot of the examples and argument for extension of `filter()` to general loops miss this point. Yes, `x for x in stuff if pred(x)` looks kinda redundant. But `transform(x) for x in stuff if pred(x)` really doesn't. And transformation in my mind is at least as common and at least as important as filtering. Happily, I can write this in Python right now: items = (transform(x) for x in stuff if pred(x)) for item in items: foo = something_with(item) bar = something_else(item) if result(foo, bar): ... I'm not making a slippery slope argument, I do know one thing is possible without the other. But if you really want an "entire comprehensions in a loop statement" we wind up with something like: for item := transform(x) for x in stuff if pred(x): foo = something_with(item) ... Which is obviously a *possible* language, but I'd be -100 on making loop statements that complicated needlessly. The way we have now is great, and clear, and already exists. Other spellings are available as well, of course, such as `if not transform(x): continue`. -- Keeping medicines from the bloodstreams of the sick; food from the bellies of the hungry; books from the hands of the uneducated; technology from the underdeveloped; and putting advocates of freedom in prisons. Intellectual property is to the 21st century what the slave trade was to the 16th.