12 lines
390 B
Text
12 lines
390 B
Text
-- HoTT
|
|
import types.sigma
|
|
open sigma sigma.ops eq
|
|
definition dpair_sigma_eq {A : Type} {B : A → Type} {u v : Σa, B a} (p : u.1 = v.1) (q : u.2 =[p] v.2)
|
|
: ⟨(sigma_eq p q)..1, (sigma_eq p q)..2⟩ = ⟨p, q⟩ :=
|
|
begin
|
|
induction u with u₁ u₂,
|
|
induction v with v₁ v₂,
|
|
esimp at q,
|
|
induction q, -- Should fail here since index p depends one index v₂
|
|
reflexivity
|
|
end
|