On 18/05/2011, at 15:55 , Roman Cheplyaka wrote: > Of course I don't claim that fusion is useless -- just trying to > understand the problem it solves. Are we saving a few closures and cons > cells here?
And thunk allocations, and thunk entries. Entering a thunk costs upwards of 20 cycles, while performing a single addition should only cost one. Imagine every thunk entry is a function call. You don't want to call a whole function just to add two numbers together. Those "few closures and cons cells" can be surprisingly expensive when compared to native ALU instructions on a modern machine. Ben. _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
