It is short and simple enough to write yourself if you need it and it encourages
bad behavior by a) always returning owned strings, b) always allocating them in
a vector. If/where possible, it is better to a) use &wstr, b) use an iterator.
In rust, it's an anti-pattern to unnecessarily abstract over allocating
operations. Some of the call sites even called split_string(..).into_iter().
This function is a hotspot, but it has inefficient codegen:
1. For whatever reason, the chars() iterator of wstr is slower
than that of a slice. Use the slice.
2. Unnecessary overflow checks were preventing vectorization.
Switch to a more optimized implementation.
This improves aliases benchmark time by about 9%.
