(px0 : a00 = a10) (px1 : a01 = a11) (p1x : a10 = a11) : {p0x : a00 = a01 & PathSquare px0 px1 p0x p1x}. Proof. exists (px0 @ p1x @ px1^). by destruct px0, px1, p1x. Defined.
Require Import Basics. Require Import Types.Paths Types.Prod. Require Import DPath. Section PathSquaresFromPaths. End PathSquaresFromPaths.