std.uni: Make auto ref adjacent

[dkorpel]

As discussed in the last DLF monthly meeting, auto ref should be adjacent.

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[TurkeyMan]

Surely auto ref const is more appropriate?

[dkorpel]

Why? I feel indifferent about the two.

[TurkeyMan]

because this is valid syntax: auto ref const(CowArray) rhs, and this is not: const(auto ref CowArray) nhs.

But in particular, parens like that are required in many cases, for instance:

struct S {
  const(T) method();
  const T method(); // not the same; this is a synonym for `T method() const`
}

Since using const(T) syntax is required for disambiguation in various circumstances, my feeling is that it's much less confusing and certainly more expected to find the const immediately before the thing that is const.
If it were up to me, I would even write it in the language spec.

[TurkeyMan]

It's a conceptual flow thing:
const auto ref T goes: type stuff (const) -> storage class stuff (auto ref) -> type stuff (T)
auto ref const T goes: storage class stuff (auto ref) -> type stuff (const T)
It's crude to interleave type stuff and storage class stuff in an arbitrary way.

[TurkeyMan]

Since it's invalid to put storage class stuff on the end (actual type must be on the end), then I would mandate that storage class stuff should go at the start, not randomly in the middle somewhere.

[dkorpel]

Makes sense, I changed it

[TurkeyMan]

🤷‍♂️