[Haskell-cafe] (state) monad and CPS
nicolas.pouillard at gmail.com
Thu Nov 12 04:27:58 EST 2009
Excerpts from wren ng thornton's message of Thu Nov 12 08:17:41 +0100 2009:
> Nicolas Pouillard wrote:
> > Excerpts from jean-christophe mincke's message of Tue Nov 10 21:18:34 +0100 2009:
> >> do acc <- get
> >> put (acc+1)
> >> ...
> > Since this pattern occurs often 'modify' is a combination of get and put:
> > do modify (+1)
> > ...
> Though the caveat about laziness applies here as well. modify is
> famously lazy which can lead to space leaks and stack overflows. Better
> would be to define and use your own strict version:
> modify' f = get >>= \x -> put $! f x
However if you want a strict state you should better use
Finally I'm wondering if  is strict enough...
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