Var is an element of type e(Val,Weight) from a weighted domain. Wvar is a
free variable unifying with the weight Weight of Var.
+Var
A weighted element.
?Wvar
Term unifying with an integer.
Description
Unifyes the weight of the term Var which should be of the form
e(Val,Weight) with Wvar. This predicate is convenient to select
elements for the labeling of weighted sets.
Fail Conditions
Fails if Var is not of the form e(Val,Weight) or if Wvar is not
unifyable with the weight.
Resatisfiable
No.
Exceptions
Examples
[eclipse 12]: E = e(1,2), el_weight(E, W).
E = e(1, 2)
W = 2
yes.