English
The family of subcomplexes of a RelCWComplex C forms a SetLike structure, where the coercion to X is E.carrier and is injective up to equality of carriers.
Русский
Множество подкомплексoв RelCWComplex C образует структуру SetLike: привод к X есть E.carrier и эта карта инъективна по носителю.
LaTeX
$$$$\text{instance: } SetLike(\text{Subcomplex } C) X\text{ with } (E \mapsto E.carrier) \text{ and } (E,F)\mapsto \text{equality constraints}$$$$
Lean4
instance : SetLike (Subcomplex C) X where
coe E := E.carrier
coe_injective' E F
h := by
obtain ⟨E, _, _, hE⟩ := E
obtain ⟨F, _, _, hF⟩ := F
congr
apply eq_of_eq_union_iUnion
rw [hE, hF]
simpa using h