rattac.
nia.
Qed.
Add Parametric Morphism : ratAdd
with signature (leRat ==> leRat ==> leRat)
as ratAdd_leRat_mor.
intuition.
eapply ratAdd_leRat_compat; trivial.
Qed.
Add Parametric Morphism : ratAdd
with signature (eqRat ==> eqRat ==> eqRat)
as ratAdd_eqRat_mor.
intuition.
eapply ratAdd_eqRat_compat; trivial.
Qed.

Theorem ratMult_eqRat_compat : forall (r1 r2 r3 r4 : Rat),
eqRat r1 r2 ->
eqRat r3 r4 ->
eqRat (ratMult r1 r3) (ratMult r2 r4).