Theorem: Matroid.contract_loops_eq (Matroid/Minor/Basic.lean)

State before:
α : Type u_1
M M' N : Matroid α
e f : α
I J R B X Y Z K C C₁ C₂ : Set α
⊢ (M ／ C).cl ∅ = M.cl C \ C
Tactic:
simp [Set.ext_iff, ← loop_iff_mem_cl_empty, contract_loop_iff_mem_cl]
State after:
no goals