@testset "Norm of polynomial" begin
    Mod.@polyvar x y
    @test norm(x) == norm(x, 2) == 1.0
    @test norm(2x) == norm(2x, 2) == 2.0
    @test norm(2x + 1) == norm(2x + 1, 2) ≈ sqrt(5)
    @test norm(2x * y + x^2 + 3) ≈ norm(2x * y + x^2 + 3, 2) ≈ sqrt(14)
end
