On Sat, Jul 11, 2009 at 12:54 PM, Derek Elkins<[email protected]> wrote: > On Fri, Jul 10, 2009 at 12:42 AM, <[email protected]> wrote: >> On Thu, 9 Jul 2009, [email protected] wrote: >> >>> You can use by lib without worrying about the CIE. You can use my library >>> without ever importing or using the word CIE. However, the CIE stuff is >>> there for those who need it. >>> >>> Perhaps I (maybe with some help) need to make a tutorial on the haskell >>> wiki to try to make it less intimidating. >> >> Okay, I threw together a quick introduction at >> <http://www.haskell.org/haskellwiki/Colour>. Any changes, comments, >> corrections, and addtions are welcome. It's a wiki! >> >> The word CIE does occur at all in the document. > > I read this and it irks me that opaque is not a monoid homomorphism > despite being the natural injection of non-transparent colours into > semi-transparent colours with pureColour being the projection back. > [Incidentally, you have a typo in pureColour, ac `over` mempty should > be ac `over` black or opaque black presumably, or even opaque mempty, > which I think was what you were going for, illustrating my point.] > It's like defining mappend on Integers as (+) and on Reals as (*); > actually, I think this is very close to what is actually happening.
I'm mistaken about the typo in pureColour, but luckily the mistake just further illustrates my point. _______________________________________________ Haskell-Cafe mailing list [email protected] http://www.haskell.org/mailman/listinfo/haskell-cafe
