Re: eqtype and functors

A better fix would be to just drop the "eq", since int is an eqtype
by definition.

	- John

On May 30, 2007, at 10:39 PM, brian wrote:

> Hi,
>
> I'm trying to use fgl (a functional graph library) and I ran across
> this:
>
> signature GRAPH_NODE =
> sig
>    eqtype node = int
> end
>
> sml throws an error on that statement.  I simply removed the "= int"
> to fix it.
>
> This change however causes another problem.  I've put the rest of it
> at the bottom of the e-mail because I think the short question is:
> what do I do to implement the intent of the original code ?
>
> Thanks
>
> Brian
>
>
> applic/lamtr.sml:128.18-128.50 Error: operator and operand don't
> agree [tycon mismatch]
>    operator domain: (int * Value.node_label list * (G.node * G.node *
> 'Z) list
>                      -> (Value.node_label,'Z) G.graph)
>                     * (int * int * CombExpr.comb_term
>                        -> int * Value.node_label list
>                           * (G.node * G.node * 'Z) list)
>    operand:         (int * Value.node_label list * (G.node * G.node *
> 'Z) list
>                      -> (Value.node_label,'Z) G.graph)
>                     * (int * int * CombExpr.comb_term
>                        -> int * Value.node_label list
>                           * (int * int * Value.edge_label) list)
>    in expression:
>      G.mkgr o UTuple.t23 o toEdgeList
>
> Here's the statement:
>
>    fun toGraph r l = (G.mkgr o UTuple.t23 o toEdgeList) (r,0,E.comb l)
>
> and it's in a functor:
>
> functor LambdaTrans (G:GRAPH) =
> struct
> ...
>
> So if I parse the error message correctly, it looks as though there
> is a problem in the the function composition.  I believe that the
> problem is toEdgeList is assuming that the node/node ID is an
> integer, when in fact it's actually a TBD type.
>
>
> ---------------------------------------------------------------------- 
> ---
> This SF.net email is sponsored by DB2 Express
> Download DB2 Express C - the FREE version of DB2 express and take
> control of your XML. No limits. Just data. Click to get it now.
> http://sourceforge.net/powerbar/db2/
> _______________________________________________
> Smlnj-list mailing list
> [email protected]
> https://lists.sourceforge.net/lists/listinfo/smlnj-list
>


-------------------------------------------------------------------------
This SF.net email is sponsored by DB2 Express
Download DB2 Express C - the FREE version of DB2 express and take
control of your XML. No limits. Just data. Click to get it now.
http://sourceforge.net/powerbar/db2/