[Haskell-cafe] Better names for

Olaf Klinke olf at aatal-apotheke.de
Thu Apr 23 14:18:59 UTC 2020

> > fmap f. If I could re-define Haskell from scratch, I'd probably
> >name
> > the Functor type class function 'map'
> As it was in Haskell 1.4

That's interesting, I did not know this. Thanks for sharing. Are there
any public records as to why the decision was made to re-name 'map' to
'fmap'? I can not find any mention in the Haskell98 report(s).
There is a stackoverflow thread (#6824255) which mentions paedagogical
reasons, simplifying error messages. 

I sometimes use the current naming 'map' to specialize a polymorphic
function to work exclusively on lists where any functor could have been
used. Other than that, I can not quite see the use in keeping 'map'
around when it is equivalent to fmap. What reasons are there apart from
backwards compatibility? Are there re-write rules that make 'map's
(operational) semantics different to 'fmap'? 


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