














September 1
%   Purpose: meta-logical operations as described in my note

:- public
	compound/1,
	copy/2,
	ground/1,
	occurs_check/2,
	occurs_in/2,
	simple/1,
	subsumes/2,
	subsumes_chk/2,
	subterm/2,
	unify/2,
	variables_of/2,
	variant/2,
	var_member_chk/2.
 
:- mode
	copy(+, ?),
	ground(+),
	    ground(+, +),
	occurs_check(+, ?),
	    occurs_check(+, +, ?),
	occurs_in(+, +),
	    occurs_in(+, +, +),
	subterm(+, ?),
	    subterm(+, +, ?),
	



























































































































































































































































































































































































































































































































































































































































































































































































































































































































