Re: [Haskell-cafe] lambda abstraction

On 6/5/11 1:33 PM, Brandon Allbery wrote:

On Sun, Jun 5, 2011 at 07:45, Patrick Browne wrote:

...

Are the following two functions equivalent? (i.e. do they describe the same computation)

let add1 a = a + 2 let add2 = \ a -> a + 2

Mostly. The monomorphism restriction can cause Haskell to restrict the type of the second to "Integer -> Integer".

Also, in GHC 7 they may have different behavior with regards to inlining. That is, GHC 7 changed its rules to only inline when the arguments to the left of "=" have been saturated (I'm not sure how this interacts with the INLINE or INLINEABLE pragma). Whether this operational difference would count as "different" depends on how fine-grained you want your operational semantics to be. It wouldn't show up in the denotational semantics side of things. -- Live well, ~wren