Iterating over types of tuple elements in @generated function

[lucas711642]

Use the fieldtypes function:

fieldtypes(Tuple{Float64, Int}) === (Float64, Int) # true

@generated function bar(t::Tuple)
    for c ∈ fieldtypes(t)
        Core.println(c)
    end
    return :( Core.println("bar !") )
end
bar((3.,1))