patch applied (ghc): Improve specialisation in SpecConstr

[Simon Peyton Jones]

Fri Sep 22 12:04:36 PDT 2006  simonpj at microsoft.com
  * Improve specialisation in SpecConstr
  
  This patch enables argToPat to look through let expressions
  
  e.g.	f (let v = rhs in \y -> ...v...)
  
  Here we can specialise for f (\y -> ...) because the rule-matcher will
  look through the let.
  

    M ./compiler/specialise/SpecConstr.lhs +7