export D2, closuresize

@enum Parity begin
    odd = -1
    even = 1
end

struct D2{T,N,M,K} <: ConstantStencilOperator
    quadratureClosure::NTuple{M,T}
    innerStencil::Stencil{T,N}
    closureStencils::NTuple{M,Stencil{T,K}}
    eClosure::Stencil{T,M}
    dClosure::Stencil{T,M}
    parity::Parity
end

function closuresize(D::D2)::Int
    return length(D.quadratureClosure)
end