include "metric_space.ma".
-record premetric_lattice_ (R : ogroup) : Type ≝ {
+record premetric_lattice_ (R : todgroup) : Type ≝ {
pml_carr:> metric_space R;
meet: pml_carr → pml_carr → pml_carr;
join: pml_carr → pml_carr → pml_carr
interpretation "valued lattice join" 'or a b =
(cic:/matita/premetric_lattice/join.con _ _ a b).
-record premetric_lattice_props (R : ogroup) (ml : premetric_lattice_ R) : Prop ≝ {
+record premetric_lattice_props (R : todgroup) (ml : premetric_lattice_ R) : Prop ≝ {
prop1a: ∀a : ml.δ (a ∧ a) a ≈ 0;
prop1b: ∀a : ml.δ (a ∨ a) a ≈ 0;
prop2a: ∀a,b: ml. δ (a ∨ b) (b ∨ a) ≈ 0;
prop5: ∀a,b,c: ml. δ (a ∨ b) (a ∨ c) + δ (a ∧ b) (a ∧ c) ≤ δ b c
}.
-record pmlattice (R : ogroup) : Type ≝ {
+record pmlattice (R : todgroup) : Type ≝ {
carr :> premetric_lattice_ R;
ispremetriclattice:> premetric_lattice_props R carr
}.
include "lattice.ma".
-lemma lattice_of_pmlattice: ∀R: ogroup. pmlattice R → lattice.
+lemma lattice_of_pmlattice: ∀R: todgroup. pmlattice R → lattice.
intros (R pml); apply (mk_lattice (apart_of_metric_space ? pml));
[apply (join ? pml)|apply (meet ? pml)
|3,4,5,6,7,8,9,10: intros (x y z); whd; intro H; whd in H; cases H (LE AP);]