11 lines
233 B
Text
11 lines
233 B
Text
import hott.path
|
|
open path
|
|
|
|
definition concat_pV_p {A : Type} {x y z : A} (p : x ≈ z) (q : y ≈ z) : (p ⬝ q⁻¹) ⬝ q ≈ p :=
|
|
begin
|
|
generalize p,
|
|
apply (path.rec_on q),
|
|
intro p,
|
|
apply (path.rec_on p),
|
|
apply idp
|
|
end
|