Style Test for Operator ^[]

constexpr auto r = ^[int];

template for (constexpr auto e : enumerators_of(^[E])) /* ... */

constexpr auto s = ^[[:R:]::inner::member];

fn<^[R]>();

fn<10, ^[R]>();

wrapper<inner_wrapper<^[T]>>

[: ^[int] :]

[:^[int]:]

constexpr auto r_of_r = ^[^[X]]

#define Reflect(X) ^[X]