Use an array. Don't remember for sure, but I think something like q = array (0, max (map fst list)) list f = (q!!) will probably work. On Fri, May 24, 2002, Carl McTague wrote:
Hi there,
is there a simple way to carry out the following type of conversion? Suppose I have a list (finite) of (value,image) pairs such as:
list = [(0,1),(1,0)]
From this I want to generate a function
f 0 = 1 f 1 = 0
Is there a way to do this? Note, I don't want to define a function that searches through the list each time it is invoked, I want to generate the function once and have it be as fast as the pattern-matcher can make it.
So, I'm looking for a function g :: [(a,b)] -> a -> b
Is this simple to do?
Thanks, Carl _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
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