module _ToSym

A type that’s explicitly convertible to a String.

Interestingly enough, most methods that accept Symbol in the standard library do not accept an object that defines .to_sym (unlike String and .to_str).

There are only two places that Symbol | _ToSym, and they’re quite obscure: - Kernel#warn‘s category: optional parameter. (Oddly enough, not for Warning.warn, though.) - TracePoint#trace’s events parameter. Additionally, the rb_iseq_load C function, only accessible through Fiddle, uses .to_sym internally.