If that's the trick you object to then you will be sad to hear that Ruby uses it.
That's a standard technique in interpreters. All non-toy Javascript engines use it, for example.
Re:A Lisp in 99LOC
by cardiffspaceman on Sunday August 17, 2025 @04:07PM
(#44934506)
Nan-boxing is awesome.
It could've used a struct rather than wedging tags into a double's first byte and still be 99 lines.