15 Jan
2002
15 Jan
'02
3 a.m.
Feuer
newtype Empty a = E ()
vs.
data Empty a = E
and
newtype Pair v w a = P (v a, w a)
vs.
data Pair v w a = P (v a) (w a)
I was wondering if anyone on this list knew of any reasons the types he chose would be more efficient than mine....
When recently reading the GHC docs, the chapter about profiling, I think, I came across something about this. From Chapter 6: | Newtypes are better than datatypes: | | If your datatype has a single constructor with a single field, | use a newtype declaration instead of a data declaration. The newtype | will be optimised away in most cases -kzm -- If I haven't seen further, it is by standing in the footprints of giants