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A comment on Javascript Arrays and Functional Programming. Parent comment

Re:Javascript Arrays and Functional Programming by moosingin3space on Thursday August 03, 2017 @03:05PM (#14922688)
The problem with this is that it generates two intermediate arrays in the maps, then effectively drops them in the reduce. This may be inefficient.

I wish that JavaScript's map/filter/reduce functions returned lazy iterators, like in Rust, so that code like this doesn't produce intermediate arrays. Does anyone know of a library that provides this?

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Re:Javascript Arrays and Functional Programming by marmart on Thursday August 03, 2017 @08:08PM (#14925251)
Those intermediate iterations could be dropped by composing the map functions together (same with the reduce), if that really was a performance bottleneck.
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Re:Javascript Arrays and Functional Programming by moosingin3space on Sunday August 06, 2017 @08:40PM (#14944543)
With lazy iterators, there is the possibility of better composition of maps/filters/reduces. That's why I'm a fan of the lazy iterators approach -- otherwise the abstraction breaks too easily and it ends up looking like a for-loop anyway.
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