Prelude.catch vs. Exception.catch

[Ashley Yakeley]

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At 2002-05-13 22:07, Ashley Yakeley wrote:

>I've noticed something a bit unusual about Exception.catch.

Curiously, the definition of Exception.evaluate given in the GHC 
Libraries documentation sec. 5.12.3 is not that actually implemented by 
GHC.

   	evaluate' :: a -> IO a;
   	evaluate' a = a `seq` return a;

"evaluate' undefined" is bottom, whereas "Expression.evaluate undefined" 
is an IO action that "fails" when executed. But both will be caught by 
Exception.catch.

-- 
Ashley Yakeley, Seattle WA

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