-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 8/27/10 22:58 , Greg wrote:
I guess the problem I'm having is finding a way to treat parametric and non-parametric types interchangeably. The syntax doesn't seem to exist that will allow me to say:
div2pi :: (Floating a) => a -> a -- for non parametric types (ie. Float) and div2pi :: (Floating b) => a b -> b -- for parametric types (ie. Foo Float)
It occurs to me that what you really want *may* be:
class (Floating a, Floating b) => TwoPi a b | a -> b where div2pi :: a -> b
which says that, given a specific type a, the compiler can infer a specific type b corresponding to it, without specifying what that type is (leaving the instance declaration to do so). - -- brandon s. allbery [linux,solaris,freebsd,perl] allbery@kf8nh.com system administrator [openafs,heimdal,too many hats] allbery@ece.cmu.edu electrical and computer engineering, carnegie mellon university KF8NH -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.10 (Darwin) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAkx4gMwACgkQIn7hlCsL25UaKwCgpe6hlJQ0yCDL2GtbO7EsrePe Cp4An3mEUz6PH23v9z0SHbmP6ikmm/yL =YIZH -----END PGP SIGNATURE-----