How to write this correct...
ahey at iee.org
Sun Feb 22 10:49:12 EST 2004
On Sunday 22 Feb 2004 10:03 am, Hans Nikolaus Beck wrote:
> I have the following problem:
> Vertex3 ist defined as
> data Vertex3 a = Vertex3 a a a
> a is defined as
> class a VertexComponent
> But I fail to write to following correct
> type GLVertex = (GLfloat, GLfloat, GLfloat)
> toVertex :: GLVertex -> Vertex3 a <<<<<<<< how do it correctly
> toVertex (x,y,z) = Vertex3 x y z
> The compiler says "cannot infer a with type GLFloat" or something like
> this.... I don't understand.
> Thank you for help
The type signature is wrong. Try this..
toVertex :: GLVertex -> Vertex3 GLfloat
toVertex :: (a,a,a) -> Vertex3 a
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