record Ext : (0 _ : AddCont) -> ComMonoid -> TypeA functor `AddCont -> [ComMon, Type]`
.shapeExt : Ext c y -> c .ShpshapeExt : Ext c y -> c .Shp.index : ({rec:0} : Ext c y) -> ComMonoidHomo (UMon c (shapeExt {rec:0})) yindex : ({rec:0} : Ext c y) -> ComMonoidHomo (UMon c (shapeExt {rec:0})) y