fact: Definition eq_exist2_l {A : Type} {P Q : A -> Prop} {u1 : A} {u2 : P u1} {u3 : Q u1} {v : { a : A | P a & Q a }} (p : u1 = proj1_sig v) (q : rew p in u2 = proj2_sig v) (r : rew p in u3 = proj3_sig v) : exist2 P Q u1 u2 u3 = v := eq_sig2 (exist2 P Q u1 u2 u3) v p q r.
imports: Notations Ltac Datatypes Logic