e: magma
}.
+(* FG: the interpretation goes just after its definition *)
+interpretation "Monoid unit" 'neutral = (e ?).
+
record isMonoid (M:PreMonoid) : Prop ≝
{ is_semi_group:> isSemiGroup M;
e_is_left_unit:
{ premonoid:> PreMonoid;
monoid_properties:> isMonoid premonoid
}.
-
-interpretation "Monoid unit" 'neutral = (e ?).
definition is_left_inverse ≝
λM:Monoid.