English
Yoneda equivalence interacts coherently with Subcomplex inclusions and morphisms.
Русский
Янида-эквив относится к подпслоям и морфизмам согласованно.
LaTeX
$$yonedaEquiv_coe {A : X.Subcomplex} {n} (f : stdSimplex.obj n ⟶ A) : …$$
Lean4
/-- Given `IsStrictSegal X`, a choice of inverse to `spine X m` for all
`m ≤ n + 1` determines an inhabitant of `StrictSegal X`. -/
noncomputable def ofIsStrictSegal [IsStrictSegal X] : StrictSegal X
where
spineToSimplex m h := Equiv.ofBijective (X.spine m) (IsStrictSegal.segal m h) |>.invFun
spine_spineToSimplex m _ := funext <| Equiv.ofBijective (X.spine m) _ |>.right_inv
spineToSimplex_spine m _ := funext <| Equiv.ofBijective (X.spine m) _ |>.left_inv