quox/lib/Quox/Thin/Coprod.idr

41 lines
1.5 KiB
Idris

module Quox.Thin.Coprod
import public Quox.Thin.Base
import public Quox.Thin.Comp
import public Quox.Thin.View
import public Quox.Thin.List
import public Quox.Thin.Cover
import Data.DPair
%default total
public export
record Coprod2 (ope1 : OPE m1 n mask1) (ope2 : OPE m2 n mask2) where
constructor MkCoprod2
{sizeMask : Nat}
{leftMask : Nat}
{rightMask : Nat}
{0 sub : OPE size n sizeMask}
{0 left : OPE m1 size leftMask}
{0 right : OPE m2 size rightMask}
0 leftComp : Comp sub left ope1
0 rightComp : Comp sub right ope2
{auto 0 isCover : Cover [left, right]}
%name Coprod2 cop
export
coprod2 : {n, mask1, mask2 : Nat} ->
(0 ope1 : OPE m1 n mask1) -> (0 ope2 : OPE m2 n mask2) ->
Coprod2 ope1 ope2
coprod2 ope1 ope2 with (view ope1) | (view ope2)
coprod2 Stop Stop | StopV | StopV = MkCoprod2 StopZ StopZ
coprod2 (Drop ope1 Refl) (Drop ope2 Refl) | DropV _ ope1 | DropV _ ope2 =
let MkCoprod2 l r = coprod2 ope1 ope2 in MkCoprod2 (DropZ l) (DropZ r)
coprod2 (Drop ope1 Refl) (Keep ope2 Refl) | DropV _ ope1 | KeepV _ ope2 =
let MkCoprod2 l r = coprod2 ope1 ope2 in MkCoprod2 (KDZ l) (KeepZ r)
coprod2 (Keep ope1 Refl) (Drop ope2 Refl) | KeepV _ ope1 | DropV _ ope2 =
let MkCoprod2 l r = coprod2 ope1 ope2 in MkCoprod2 (KeepZ l) (KDZ r)
coprod2 (Keep ope1 Refl) (Keep ope2 Refl) | KeepV _ ope1 | KeepV _ ope2 =
let MkCoprod2 l r = coprod2 ope1 ope2 in MkCoprod2 (KeepZ l) (KeepZ r)
-- [todo] n-ary coprod