[Haskell-cafe] sizeOf on a type

Henning Thielemann lemming at henning-thielemann.de
Thu Jan 14 12:51:55 EST 2010


On Fri, 25 Dec 2009, Lennart Augustsson wrote:

> sizeOfPtr :: Ptr a -> Int
> sizeOfPtr = sizeOf . (undefined :: Ptr a -> a)
>
> No need for scoped type variables.  But it does assume sizeOf does not
> use its argument.

That's even better. I'll add that to the Wiki.

   http://www.haskell.org/haskellwiki/Scoped_type_variables#Avoiding_Scoped_Type_Variables


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