Thank you all for your answers! I indeed do not want to use CVS HEAD, but it's nice to know that there will be a better solution some time. Until then I will write s.th. like loop (residual :: MutableGraph state node weight) flow absValue = ... which is completely sufficient for my purposes (implementing my Java homework in the imperative language of my choice)... Merry christmas, Chris Am 24.12.2004 um 14:33 schrieb Arthur Baars:
You could also do it with the current implementation of scoped type variables. So you don't need to compile the CVS HEAD version. Note that you need the pattern (n1::a) and/or (n2::a) to introduce the scoped type variable, which was not necessary in Ralf's solution.
{-# OPTIONS -fglasgow-exts #-} add :: Num a => a -> a -> a add (n1::a) n2 = addToN1 n2 where addToN1 :: a -> a addToN1 number = n1 + number