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[Alanna Zito <zito AT cs.queensu.ca>]

I am trying to define some operations that take two objects and return 
true if the objects match or are equal (based on certain criteria).  I 
have been able to define similar operations and equations that take 
sorts, but when I try to do something equivalent with classes, I get a 
parse error when I try to load the module - I can't figure out if it's 
just a syntax error that I'm missing, or if I'm trying to do something 
illegal.   Here is a simple example of what I am trying to do (where two 
Properties "match" if they have the same value for the attribute "lower"):

(omod TEST is
  protecting BOOL .
  protecting NAT .
  class Property | lower : Nat .
  op matches : Property Property -> Bool .

  vars P1, P2 : Oid .
  var L : Nat  .

  eq matches ( < P1 : Property | lower : L > , < P2 : Property | lower 
: L > ) = true .
  eq matches ( X:Property , Y:Property ) = false [owise] .
endom)

This gives the error

Warning: Parse error in (matches(< <---*HERE*
Error: no parse for eq matches(< P1 : Property | lower : L >,< P2 : 
Property |
   lower : L >) ~ true

Does anyone know what I'm doing wrong, or if there's a better way to do 
this?

Thank you,

Alanna