Theorem: Set.empty_subset (GMLInit/Data/Set/Subset.lean)

State before:
α : Sort u_1
s✝ t u s : Set α
⊢ Set.empty.Subset s
Tactic:
intro x h
State after:
α : Sort u_1
s✝ t u s : Set α
x : α
h : x ∈ Set.empty
⊢ x ∈ s

State before:
α : Sort u_1
s✝ t u s : Set α
x : α
h : x ∈ Set.empty
⊢ x ∈ s
Tactic:
contradiction
State after:
no goals