Synonym Type Constructors
Ashley Yakeley
ashley@semantic.org
Mon, 19 Feb 2001 03:53:11 -0800
I don't know if this is a bug in Hugs 98, or whether it's a
misunderstanding of mine.
The Haskell 98 Report Sec. 4.2.2 claims that 'type' introduces a new type
constructor. Yet it doesn't seem possible to declare the type constructor
an instance of a class:
--
class MyClass c where
foo :: a -> c a
type T m = IO m
instance MyClass T where
foo = return
--
Hugs gives:
(line 6): Not enough arguments for type synonym "T"
So is T a real type constructor or not?
--
Ashley Yakeley, Seattle WA