val lookup :
int -> 'a Terms.substitution -> 'a Terms.foterm
val filter : 'a Terms.substitution -> Terms.varlist -> Terms.varlist
+ val reloc_subst :
+ 'a Terms.substitution -> 'a Terms.foterm -> 'a Terms.foterm
val apply_subst :
'a Terms.substitution -> 'a Terms.foterm -> 'a Terms.foterm
+ val flat:
+ 'a Terms.substitution -> 'a Terms.substitution
val concat:
'a Terms.substitution -> 'a Terms.substitution ->
'a Terms.substitution