[Haskell-cafe] Inferring rewrite rules for higher order functions

Dear list, with rewrite rules I can tell the compiler to replace "map id" by "id", but I still have to write that rule by hand. Does anyone of you know about research into inferring such a rewrite rule automatically? I could imagine that for a function of type "f :: some -> args -> T a -> T b" and not-too-bad type constructors T it might be possible under what conditions on "some" and "args" infer when "f arg1 arg2 = id" holds, and if the conditions are fulfilled by functions like "id", generate a rewrite rule "f id id = id" automatically. Thanks, Joachim -- Joachim "nomeata" Breitner mail@joachim-breitner.de | nomeata@debian.org | GPG: 0x4743206C xmpp: nomeata@joachim-breitner.de | http://www.joachim-breitner.de/