diff options
Diffstat (limited to 'theories/Init/Logic.v')
| -rw-r--r-- | theories/Init/Logic.v | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/theories/Init/Logic.v b/theories/Init/Logic.v index f659c31f9..3eefe9a84 100644 --- a/theories/Init/Logic.v +++ b/theories/Init/Logic.v @@ -223,7 +223,7 @@ Proof. Qed. (** [(IF_then_else P Q R)], written [IF P then Q else R] denotes - either [P] and [Q], or [~P] and [Q] *) + either [P] and [Q], or [~P] and [R] *) Definition IF_then_else (P Q R:Prop) := P /\ Q \/ ~ P /\ R. @@ -609,6 +609,11 @@ Proof. destruct 1; auto. Qed. +Lemma inhabited_covariant (A B : Type) : (A -> B) -> inhabited A -> inhabited B. +Proof. + intros f [x];exact (inhabits (f x)). +Qed. + (** Declaration of stepl and stepr for eq and iff *) Lemma eq_stepl : forall (A : Type) (x y z : A), x = y -> x = z -> z = y. |