One of the things haskell can do with lazy sequences is fuse away intermediate d...

surrealize on Nov 25, 2012 | parent | context | favorite | on: How is lazy evaluation in Haskell useful?

One of the things haskell can do with lazy sequences is fuse away intermediate data structures, e.g. take

  map f . map g

and substitute

  map (f . g)

automatically (as a compiler optimization). I don't think that's a safe transformation in general in a non-pure language; not sure about a pure strict language.

ibotty on Nov 26, 2012 [–]

yes, that's possible in a pure referential transparent language (strict or lazy is not the point).