The name escapes me but any category theory book should supply the answer. Dominic. Tom Pledger <Tom.Pledger@peace.com>@haskell.org on 27/03/2002 04:22:29 Sent by: haskell-cafe-admin@haskell.org To: haskell-cafe cc: bcc: Subject: Is there a name for this structure? Joe English writes: : | Suppose you have two morphisms f : A -> B and g : B -> A | such that neither (f . g) nor (g . f) is the identity, | but satisfying (f . g . f) = f. Is there a conventional name | for this? Is it equivalent to saying that (f . g) is the identity on the range of f? That's shorter, though still not a snappy single word term. _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ------------------------------------------------------------------------------------------------- Save time by using an eTicket and our Self-Service Check-in Kiosks. For more information go to http://www.britishairways.com/eservice1