From Haskell' ticket #76:
http://hackage.haskell.org/trac/haskell-prime/wiki/BangPatterns
> The main idea is to add a single new production to the syntax
> of patterns
> pat ::= !pat
Experiments (ghci -fbang-patterns -O2 -S, rename identifiers, then diff)
shows that nested pattern bindings are equivalent to the outermost binding:
!(!pat) ==> !pat
!(~pat) ==> !pat
~(~pat) ==> ~pat
~(!pat) ==> ~pat
but I do not see any wording to that effect either in the Haskell 98
report, the GHC documentation, or the Haskell' wiki. Have I overlooked
it, or does it follow from the existing language definition?
Dan
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