Files
agda-spa/lean/Spa/Lattice/IterProd.lean
2026-06-25 18:55:09 -05:00

36 lines
905 B
Lean4
Raw Blame History

This file contains ambiguous Unicode characters
This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.
import Spa.Lattice.Prod
import Spa.Lattice.Unit
namespace Spa
universe u
def IterProd (A B : Type u) : Type u
| 0 => B
| k + 1 => A × IterProd A B k
namespace IterProd
variable {A B : Type u}
instance decidableEq [DecidableEq A] [DecidableEq B] :
k, DecidableEq (IterProd A B k)
| 0 => inferInstanceAs (DecidableEq B)
| k + 1 => @instDecidableEqProd A (IterProd A B k) _ (decidableEq k)
def build (a : A) (b : B) : (k : ) IterProd A B k
| 0 => b
| k + 1 => (a, build a b k)
def fixedHeight [FiniteHeightLattice A] [FiniteHeightLattice B] :
k, FiniteHeightLattice (IterProd A B k)
| 0 => inferInstanceAs (FiniteHeightLattice B)
| k + 1 => @Spa.prod A (IterProd A B k) _ (fixedHeight k)
instance finiteHeight [FiniteHeightLattice A] [FiniteHeightLattice B] (k : ) :
FiniteHeightLattice (IterProd A B k) := fixedHeight k
end IterProd
end Spa