Theorem: CategoryTheory.List.joinF.associatorLeft_nil (Moncalc/CategoryTheory/List/Monad.lean)

State before:
α : Type u
inst✝ : Category α
⊢ joinF.associatorLeft [] = 𝟙 []
Tactic:
unfold joinF.associatorLeft
State after:
α : Type u
inst✝ : Category α
⊢ associatorLeft.aux [] [] [] = 𝟙 []

State before:
α : Type u
inst✝ : Category α
⊢ associatorLeft.aux [] [] [] = 𝟙 []
Tactic:
rfl
State after:
no goals