[Haskell-cafe] Polymorphic algebraic type constructors

John Meacham john at repetae.net
Wed Jun 23 18:11:32 EDT 2004

There is a fundamental problem with assuming all []'s are equal even if
they are empty lists of different things. mainly, that they arn't! 

; ghci
Prelude> print ([]::[Int])
Prelude> print ([]::[Char])

Remember, in haskell, values may depend on types. Just because the type
is not explicitly expressed in the pattern, it doesn't mean it isn't
there and passed around behind the scenes.

John Meacham - ⑆repetae.net⑆john⑈ 

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