10 lines
205 B
Text
10 lines
205 B
Text
import algebra.ring
|
|
open algebra
|
|
|
|
definition foo {A : Type} [s : monoid A] (a : A) :=
|
|
a * a
|
|
|
|
example {A : Type} [s : comm_ring A] (a b : A) (H : foo a = a) : a * a = a :=
|
|
begin
|
|
rewrite [↓foo a, H]
|
|
end
|