lean2/tests/lean/run/eqv_tacs.lean

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open nat
example (a : nat) : a + 0 = a :=
by reflexivity
example (a : Prop) : a ↔ a :=
by reflexivity
example (a b : Prop) : (a ↔ b) → (b ↔ a) :=
by intros; symmetry; assumption
example (a b c : nat) : a = b → b = c → c = a :=
begin
intros,
symmetry,
transitivity b,
repeat assumption
end
example (a b c : Prop) : (a ↔ b) → (b ↔ c) → (c ↔ a) :=
begin
intros,
symmetry,
transitivity b,
repeat assumption
end
example {A B C : Type} (a : A) (b : B) (c : C) : a == b → b == c → c == a :=
begin
intros,
symmetry,
transitivity b,
repeat assumption
end