Section Permutation_properties.
Variable A:Type.
Implicit Types a b : A.
Implicit Types l m : list A.
(** Compatibility with others operations on lists *)
Global Instance Permutation_in' :
Proper (Logic.eq ==> @Permutation A ==> iff) (@In A) | 10.
Global Instance Permutation_app' :
Proper (@Permutation A ==> @Permutation A ==> @Permutation A) (@app A) | 10.

Lemma Permutation_cons_append : forall (l : list A) x,
Permutation (x :: l) (l ++ x :: nil).