qtpy VS kiwi

They're basically identical as far as I've seen through using PyQt5 then Pyside6. Either way, I'd recommend just using qtpy. Then if you need to switch for license reasons or whatever, it's as easy as installing the other lib and changing an env variable

Nucleic also makes Kiwi one of the fastest Cassowary Constraint implementations. It is very useful for implementing custom GUIs as it can make building internal component layouts and general layout systems fairly straightforward and it’s very performant.

I highly encourage taking a look at it and it has also been ported to a wide range of language.

I’m using Nim kiwi with my own GUI library now. I’ll have to take a peak at how enaml is using kiwi for its layouts.

https://kiwisolver.readthedocs.io/en/latest/

https://github.com/alexbirkett/kiwi-java

https://github.com/PongoEngine/jasper

https://github.com/yglukhov/kiwi

If any of the Luau devs are watching this, please flesh out the metamethods. I'd switch almost everything to Luau if they were improved.

They're the biggest PITA right now as designed in PUC-Rio, and I see that while you've improved upon __eq, other metamethods are still lacking.

In PUC-Rio, boolean equality operators FORCE a boolean result, regardless of what you return. Ideally they would allow returning any result type, which then can be coerced to boolean later (e.g. by an `if` statement), just like the arithmetic operators do.

Further, `__neq`, `__ge` and `__gt` do not exist. They should.

The lack of a proper metamethod design means that binding to e.g. Kiwi[0] is impossible without some incredibly fugly hacks. It has been a long-standing annoyance with Lua in an otherwise beautiful little scripting language (that I use frequently).

This looks quite nice - lots of attempts in this space but nothing that attempts to match Lua to this degree.

[0] https://github.com/nucleic/kiwi