
?Set1 subsetof ?Set2

   Set1 is a (non-strict) subset of the integer set Set2

Arguments
   Set1                a set, set variable, free variable or set expression
   Set2                a set, set variable or set expression

Type
   library(fd_sets)

Examples
   
    	?- X subset [1,2,3].
	X = X{([] .. [1, 2, 3]) : _398{0 .. 3}}

	?- X subsetof [1,2,3], Y subsetof X.
	X = X{([] .. [1, 2, 3]) : _398{0 .. 3}}
	Y = Y{([] .. [1, 2, 3]) : _531{0 .. 3}}

	?- [1,2,3] subsetof Y.
	instantiation fault
    


