fact: Fixpoint set_of_variables_in_range_of_subst (sigma : substitution) : VSet.t := match sigma with | nil => VSet.empty | (_,t) :: sigma => VSet.union (set_of_variables t) (set_of_variables_in_range_of_subst sigma) end.
imports: Coq(Arith Wf_nat Wellfounded List Multiset Relations) CoLoR(closure decidable_set ordered_set more_list list_permut list_set list_sort dickson term_spec term)