Hello, I have the following very “simple” code

```
f(Λ, inds) where {T,N} = Λ[inds...] *= -1
x = [1,2,3,4]
@code_warntype f(x, [1:2])
```

But this seams to be type unstable:

```
Variables:
#self# <optimized out>
Λ::Array{Int64,1}
inds::Array{UnitRange{Int64},1}
Body:
begin
(Core._apply)(test.setindex!, (Core.tuple)(Λ::Array{Int64,1}, -1)::Tuple{Array{Int64,1},Int64}, inds::Array{UnitRange{Int64},1})::Any
return -1
end::Int64
nothing
```

Why is it so? And what would be the right way to multiply (apply a function) on **some** values of an Array without allocation and with type stability… I cannot figure it out.