mapRecordField

[Serge D. Mechveliani]

People,

ghc-6.10.1  says it provides a `sugar' syntax for records:
wild-card patterns, punning, and field disambiguation.

For example, I write     fam {opAttrs = cp $ opAttrs fam}

to map the function  cp  to the field  opAttrs  in the record  fam.
The best expression for this could be
                                      mapField opAttrs cp fam,

with an intended library function  mapField   -- which does not agree
with Haskell types. 
But as GHC takes care to provide a language extension for records, 
maybe it could introduce   mapField  as the language construct and 
as a reserved word?
Also I do not know, maybe, something like  fam {opAttrs = cp opAttrs}
is possible now?

Thank you in advance for your explanation,

-----------------
Serge Mechveliani
mechvel at botik.ru