David House wrote:
http://en.wikibooks.org/wiki/Haskell/Category_theory I'd love comments from newcomers and experts alike regarding my approach, the content, improvements and so on. Of course, it's on the wikibook, so if you have anything to add (that's not _too_ substantial otherwise I'd recommend discussion first) then go ahead.
Hi David, In the introduction you say that Set is the category of all sets with morphisms as standard functions and composition as standard function composition. But in the second exercise in the intro it's clear that function composition is not associative. Therefore surely this means everything based on function composition can't be a category? Also, why does this exercise contain redundant morphisms (I hope I'm not spoiling it for anyone by saying this or perhaps I've just totally misunderstood everything)? Thanks, Brian. -- http://www.metamilk.com