[mi_lk]

Had a good chuckle

[abcd_f]

If it weren't for Bool as a name, that's just 0 for OK, non-zero for errors with 1 being general failure.

[inigyou]

TDWTF code is usually hyperbolized. It might not have been called Bool.

[WorldMaker]

But also it could have been found in the wild in C/C++ code, which both had no "native" Boolean type until surprisingly recently (C++17 and C23! as in 2017 and 2023 standards, irrespectively) so Bool is very much a possible real name and not part of the hyperbole.