Section Length_4.
Context `{TnEQD:Tarski_neutral_dimensionless_with_decidable_point_equality}.
Notation "l1 =l= l2" := (EqL l1 l2) (at level 80, right associativity).

Lemma all_eql : forall A B l1 l2, Len A B l1 -> Len A B l2 -> EqL l1 l2.