[Haskell-cafe] Map list of functions over a single argument

David Roundy droundy at darcs.net
Tue Feb 20 11:13:08 EST 2007


On Tue, Feb 20, 2007 at 02:07:08PM +0000, Paul Moore wrote:
> I'm after a function, sort of equivalent to map, but rather than
> mapping a function over a list of arguments, I want to map a list of
> functions over the same argument. The signature would be [a -> b] -> a
> -> [b], but hoogle didn't come up with anything.
> 
> It seems like an obvious analogue of map, so I'm pretty sure I'm
> missing something (otherwise, I'd just write it myself, and not bother
> :-))
> 
> Can anyone point me in the right direction?

It's rather a small function to bother putting in the libraries, and I
think better expressed using map directly:

rmap fs x = map ($ x) fs
-- 
David Roundy
http://www.darcs.net


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