Re: [Haskell-cafe] Callback functions?

http://cvs.haskell.org/cgi-bin

/cvsweb.cgi/fptools/libraries/GLUT/examples/RedBook/

Ok, I'll take a look

What makes a callback different from any other kind of function?

Well... what about inside monads? Does this break purity??? Does this require adding IO to the monad if the callback function does IO? As I'm writing this I kindof have this sense inside me that this is a really newbie-ish question. That the answer is no it doesnt break purity, yes it does require adding IO to the monad, but I'm asking anyway just to check :-) On 7/3/07, Dan Piponi wrote:

On 7/2/07, Hugh Perkins wrote:

...

Anyway, so the question is: how do we write callback functions in FP/Haskell? Can someone provide a simple, but functional example?

What makes a callback different from any other kind of function? In Haskell, as in other functional programming languages, you're completely free to pass functions into other functions and store them in datastructures. Take a look at the 'callbacks' used in the HOpenGL examples. They're just ordinary functions:

http://cvs.haskell.org/cgi-bin/cvsweb.cgi/fptools/libraries/GLUT/examples/Re... -- Dan _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe