A short derivation: An obvious solution is: Use a lambda abstraction: appPair (\x -> (x b) * velocityC) (cos,sin) or (using function composition) appPair ((* velocityC) . (\x -> x b))(cos,sin) or (explictly using the application operator $): appPair ((* velocityC) . (\x -> x $ b))(cos,sin) Now the lambda abstraction can be removed appPair ((* velocityC ) . ($ b)) (cos,sin) Regards, David Am 01.12.2012 23:31, schrieb Christopher Howard:
Can application of an expression (to a function) be treated like a function itself? In my specific case, I started with this expression:
code: -------- (cos b * velocityC, sin b * velocityC) --------
But I have a compulsive hatred of duplication. I happened to have this function handy called appPair:
code: ------- appPair f (a, b) = (f a, f b)
appPair (* velocityC) (cos b, sin b) -------
Better, but the b identifier is still duplicated. Is there some way I could have...
code: -------- appPair (?) (cos, sin) --------
...shifting the application of b into the (* velocityC) expression, without modifying my appPair function?
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