Convenient null-terminated string literals

libs
14

I agree that performing an unguaranteed transmute is far from ideal, but for some reason CStr showcases no const constructor (not even from_bytes_with_nul? It's compatible with the thin pointer implementation). So the only non-UB solution right now is to use our own wrapper type that delegates the construction to runtime:

struct ImplIntoCStr<'lt>(&'lt [u8]);

const unsafe fn cstr_from_bytes_with_null (bytes: &'_ [u8])
  -> ImplIntoCStr<'_>
{
    /* const */ impl<'lt> Into<&'lt CStr> for ImplIntoCStr<'lt> { … }

    ImplIntoCStr(bytes)
}