id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	os	architecture	failure	difficulty	testcase	blockedby	blocking	related
1497	Rebinding (:) -- built-in syntax, or just another constructor?	dons		"This program is valid in Hugs 2005, but not in GHC:

{{{

import Prelude (print,(<),Bool(..))

data Cond a = a : a

infixl 0 ?
infixl 1 :

(?) :: Bool -> Cond a -> a
True  ? (x : _) = x
False ? (_ : y) = y

main = print (1 < 2 ? ""yeah"" : ""no!"")

}}}

Hugs responds with:

{{{
Main> main
""yeah""
}}}

GHCi says:

{{{
$ ghci A.hs
A.hs:4:16: Illegal binding of built-in syntax: :
}}}

Which one is right?"	bug	closed	low		Compiler (Parser)	6.6	invalid			Unknown/Multiple	Unknown/Multiple		Easy (less than 1 hour)