Ruby core classes mostly force == and != to true/false

[taw]

So we need to override ==/!= on TrueClass, FalseClass, Float, Integer, Rational, etc.

This could cause performance issues, but the alternative is a lot of brokenness. Perhaps we need a bit of C to improve performance here.

This used to sort of work, but not in any consistent way.

[taw]

This is done now, it still doesn't quite handle all cases (specs have the failing cases).

[Unihedro]

Btw how do you plan on handling .eql? and .equal?

[taw]

That would be mainly useful for keying by Z3 AST object?

I think this should already work, since they're all immutable and Z3 interns them, so actually same object should be returned for anything identical.

Z3 objects shouldn't .eql? or .equal? anything else, so I do't think we need to override anything.

(unless I'm missing something)