Add map/filter/reduce/range/all/any to avoid accidental bugs in for loops

[vietlq]

The for loops are too verbose and any user can make mistake when increasing/decreasing counters: makoto/blockparty#175

It would be much better to have map/filter/reduce/range/all/any like in Python so people can iterate and apply input in consistent and uniform way that is safe and easy to read.

You may refer to all built-in Python functions here:

https://docs.python.org/2/library/functions.html

[chriseth]

While this is a good idea, most of the operations that could benefit from that are rather expensive so it is questionable whether such things would be used much, but as I said, still nice to have.

This probably requires #911 and perhaps even #869 to be really useful.

[leonardoalt]

I don't think it'd need #869, unless it supports more than arrays., but I think it needs #911 with capturing

[axic]

We discussed as part of https://twitter.com/nomorebear/status/1254000358361186306, range based loops would have avoided some mistakes. (But also unit testing would avoid them too)

[Marenz]

I am absolutely in favor of range-based loops at the very least.

[github-actions]

Hi everyone! This issue has been closed due to inactivity.
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