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hellertime/specialize-handle.lhs

Created November 2, 2010 02:15
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Control.Exception.handle is ambiguous in its type, you must provide a type signature for it to type-check.
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specialize-handle.lhs
> import Control.Exception ( handle, IOException )
here is a specialize handle which deals with IOExceptions
> handleIO :: (IOException -> IO a) -> IO a -> IO a
> handleIO = handle
Without this added signature you will get type-check errors like this:
Ambiguous type variable `e' in the constraint:
`GHC.Exception.Exception e'
arising from a use of `handle'
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