21 lines
331 B
Text
21 lines
331 B
Text
import logic
|
|
open eq
|
|
section
|
|
variable {A : Type}
|
|
theorem T {a b : A} (H : a = b) : b = a
|
|
:= symm H
|
|
variables x y : A
|
|
variable H : x = y
|
|
check T H
|
|
check T
|
|
end
|
|
|
|
section
|
|
variable {A : Type}
|
|
theorem T2 ⦃a b : A⦄ (H : a = b) : b = a
|
|
:= symm H
|
|
variables x y : A
|
|
variable H : x = y
|
|
check T2 H
|
|
check T2
|
|
end
|