Re: Performance: Faster to define a function writing out all arguments?

alexander.fuchs:

Hi there,

I am trying to write my first serious Haskell program, but have problems understanding 'strange' performance results. It seems to be a ghc specific question, so I am asking here.

In a happy parser I have this code 1):

%monad { Parsed } { thenP } { returnP }

type Parsed = State Env.Env

returnP :: a -> Parsed a returnP a = return a

thenP :: Parsed a -> (a -> Parsed b) -> Parsed b thenP x k = x >>= k

An alternative was this 2) (yes, redundant in happy):

returnP :: a -> Parsed a returnP = return

thenP :: Parsed a -> (a -> Parsed b) -> Parsed b thenP = (>>=)

Could you submit a minimal, complete grammar file, so we can look at the generated code? -- Don