Re: specify call-by-need

2011-02-18 Thread Malcolm Wallace
On 16 Feb 2011, at 01:53, Scott Turner wrote: In practice, Haskell a call-by-need language. Still, software developers are not on firm ground when they run into trouble with evaluation order, because the language definition leaves this open. Is this an underspecification that should be fixed?

Re: specify call-by-need

2011-02-15 Thread Scott Turner
On 2011-02-15 21:12, John Meacham wrote: > Except for the fact that compilers don't actually implement call by > need. An example would be the speculative evaluation of ghc. An interesting option. The things I've read say that it's not in the released ghc. > And local optimizations that affect as

Re: specify call-by-need

2011-02-15 Thread John Meacham
Except for the fact that compilers don't actually implement call by need. An example would be the speculative evaluation of ghc. http://research.microsoft.com/en-us/um/people/simonpj/papers/optimistic/adaptive_speculation.ps And local optimizations that affect asymptotic behavior are used all the

specify call-by-need

2011-02-15 Thread Scott Turner
In practice, Haskell a call-by-need language. Still, software developers are not on firm ground when they run into trouble with evaluation order, because the language definition leaves this open. Is this an underspecification that should be fixed? 1. Haskell programmers learn the pitfalls of sh