Theorem: Matroid.cl_singleton_eq (Matroid/Simple.lean)

State before:
α : Type u_1
M N : Matroid α
e f g : α
I X P D : Set α
inst✝ : M.Simple
he : autoParam (e ∈ M.E) _auto✝
⊢ M.cl {e} = {e}
Tactic:
rw [cl_eq_parallel_class_union_loops, parallel_class_eq he, cl_empty_eq_empty, union_empty]
State after:
no goals