Theorem: LoVe.BackwardProofs.modus_ponens (LoVe/Lectures/LoVe03_BackwardProofs_Demo.lean)

State before:
a b : Prop
⊢ (a → b) → a → b
Tactic:
intro hab ha
State after:
a b : Prop
hab : a → b
ha : a
⊢ b

State before:
a b : Prop
hab : a → b
ha : a
⊢ b
Tactic:
apply hab
State after:
a b : Prop
hab : a → b
ha : a
⊢ a

State before:
a b : Prop
hab : a → b
ha : a
⊢ a
Tactic:
exact ha
State after:
no goals