A question about the "awkward squad"

Simon Marlow simonmar at microsoft.com
Mon Dec 6 08:36:56 EST 2004


On 06 December 2004 13:25, Simon Peyton-Jones wrote:

>>> and is it (still?) true that GHC never expands them?
>> 
>> I'm not sure if GHC guarantees never to duplicate a redex, Simon PJ
>> might know.
> 
> Yes, it's very careful not to duplicate a redex, except for ones of
> known bounded size, like x +# y, where sharing the work costs more
> than duplicating int.  

I seem to recall that redexes of "known bounded size" includes

   case z of (a,b) -> e

right?  We sometimes push case expressions inside lambdas to bring
lambdas together, for example.

Cheers,
	Simon


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