19 lines
702 B
Text
19 lines
702 B
Text
/- intro tactic variants -/
|
||
|
||
example (p q : α → Prop) : (∃ x, p x ∧ q x) → ∃ x, q x ∧ p x := by
|
||
intro h
|
||
match h with
|
||
| Exists.intro w (And.intro hp hq) => exact Exists.intro w (And.intro hq hp)
|
||
|
||
example (p q : α → Prop) : (∃ x, p x ∧ q x) → ∃ x, q x ∧ p x := by
|
||
intro (Exists.intro _ (And.intro hp hq))
|
||
exact Exists.intro _ (And.intro hq hp)
|
||
|
||
example (p q : α → Prop) : (∃ x, p x ∧ q x) → ∃ x, q x ∧ p x := by
|
||
intro ⟨_, hp, hq⟩
|
||
exact ⟨_, hq, hp⟩
|
||
|
||
example (α : Type) (p q : α → Prop) : (∃ x, p x ∨ q x) → ∃ x, q x ∨ p x := by
|
||
intro
|
||
| ⟨_, .inl h⟩ => exact ⟨_, .inr h⟩
|
||
| ⟨_, .inr h⟩ => exact ⟨_, .inl h⟩
|