val lookup_subst :
int -> B.t Terms.substitution -> B.t Terms.foterm
val filter : B.t Terms.substitution -> Terms.varlist -> Terms.varlist
+ val apply_subst :
+ B.t Terms.substitution -> B.t Terms.foterm -> B.t Terms.foterm
+ val concat:
+ B.t Terms.substitution -> B.t Terms.substitution ->
+ B.t Terms.substitution
end