Theorem: Digraph.set_walk_length_zero_eq_of_ne (GraphProjects/DigraphConnectivity.lean)

State before:
V : Type u
V' : Type v
V'' : Type w
G : Digraph V
G' : Digraph V'
G'' : Digraph V''
u v : V
h : u ≠ v
⊢ {p | Walk.length p = 0} = ∅
Tactic:
ext p
State after:
case h
V : Type u
V' : Type v
V'' : Type w
G : Digraph V
G' : Digraph V'
G'' : Digraph V''
u v : V
h : u ≠ v
p : Walk G u v
⊢ p ∈ {p | Walk.length p = 0} ↔ p ∈ ∅

State before:
case h
V : Type u
V' : Type v
V'' : Type w
G : Digraph V
G' : Digraph V'
G'' : Digraph V''
u v : V
h : u ≠ v
p : Walk G u v
⊢ p ∈ {p | Walk.length p = 0} ↔ p ∈ ∅
Tactic:
simp only [Set.mem_setOf_eq, Set.mem_empty_iff_false, iff_false_iff]
State after:
case h
V : Type u
V' : Type v
V'' : Type w
G : Digraph V
G' : Digraph V'
G'' : Digraph V''
u v : V
h : u ≠ v
p : Walk G u v
⊢ ¬Walk.length p = 0

State before:
case h
V : Type u
V' : Type v
V'' : Type w
G : Digraph V
G' : Digraph V'
G'' : Digraph V''
u v : V
h : u ≠ v
p : Walk G u v
⊢ ¬Walk.length p = 0
Tactic:
exact fun h' => absurd (Walk.eq_of_length_eq_zero h') h
State after:
no goals