[Haskell-cafe] PatternSignatures (rant)

Henning Thielemann lemming at henning-thielemann.de
Wed Apr 8 19:13:58 EDT 2009


On Wed, 8 Apr 2009, Johannes Waldmann wrote:

> Dear all, (this is a rant - please ignore)
>
> why has "PatternSignatures"
> been renamed to "ScopedTypeVariables" (in ghc-6.10)?
>
> show me the alleged "type variable" in this code:
> do x :: Int <- [ 1 .. 10 ] ; return $ x^2
>
> and why on earth do I need to use a language extension at all
> to get to the most basic thing of declarative programming:
> to declare the type of an identifier?

This would work:
   do x <- [ 1 .. 10 ] ; return $ (x::Int)^2

but I assume, that you want to declare the type on binding, right?


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