possibility for better type inference with Vararg?

[simeonschaub]

Since for example Vararg{Any,Int} throws an error during construction, would it be possible to take advantage of the fact that the N parameter in a Vararg is always an Int in type inference? It would be nice if the following inferred more precisely:

julia> f(::NTuple{N}) where {N} = N
f (generic function with 1 method)

julia> code_warntype(f, Tuple{Tuple})
Variables
  #self#::Core.Compiler.Const(f, false)
  #unused#::Tuple{Vararg{T,N}} where T where N

Body::Any
1 ─     return $(Expr(:static_parameter, 1))

Sorry if there is an issue about this already, but I couldn't find one.

[fredrikekre]

#37316 ?

[simeonschaub]

Weird, sorry for that!