@traitfn with multiple traits

[ChenZhao44]

I am trying to define a method with arguments of multiple traits.

using SimpleTraits
@traitdef Foo{T}
@traitdef Bar{T}

@traitfn f(::S, ::T) where {S, T; Foo{S}, Bar{T}} = nothing

I expect the macro @traitfn will generate a method like

f(::Type{Foo{S}}, ::Type{Bar{T}}, ::S, ::T) where {S, T}

However, it only generated

f(::Type{Foo{S}}, ::S, ::T) where {S, T}

Please correct me if my understanding on trait is wrong.