projog

3.37. X@=<Y - term "less than or equal" test.

Succeeds when the term argument X is less than or equal to the term argument Y.

Examples

?- b@=<a.

no

?- b@=<b.

yes

?- b@=<c.

yes

?- b@=<1.

no

?- b@=<b(a).

yes