Make Prelude's map = fmap

wren ng thornton wren at
Sat Jun 22 00:11:10 CEST 2013

On 6/21/13 5:12 PM, Matthias Kilian wrote:
> On Fri, Jun 21, 2013 at 04:53:49PM -0400, Carter Schonwald wrote:
>> I'd support the map=fmap thing,
> Does it cause any consequences for existing libraries and programs?
> Does it break any existing Haskell98 (or Haskell2010) code?
> If not: fine. But if yes: please don't do it.

As with the Foldable/Traversable stuff, there's the impediment of ensuring
that list fusion still works right.

This is hopefully a minor issue and can be easily resolved by
inlining/monomorphizing at the appropriate stage; however, it is a
technical issue that needs to be addressed by the time we actually
implement the change.

Live well,

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