This is incredibly efficient and smart. Good on you Amelia.

The use of 0xAAAAAAAA is clever because it effectively simulates the process of negabinary conversion through simple bitwise operations. The addition and subtraction of 0xAAAAAAAA, combined with the XOR operation, effectively handle the negabinary's alternating sign in the place value.

Efficient because it leverages the processor's native ability to perform bitwise operations quickly, rather than using loops or recursive calls. Lovely.

Hack U😍

greet_extraterrestrials as required by the Kata description, should be "... Therefore, define a static class method called greet_extraterrestrials which accepts an argument...", but yours doesn't look like static to me.

Also this means, that the test should be tested in the tests with ReflectionMethod::isStatic may be?

It may look overkill for advanced users, but it's actually good for programmers who's still studying.

This is deliberately overkill; it's an explanation of available OOP class features with scoping.

Looks like overkill. In my opinion readability is poor, especially class property section.

Impressive, so many different implementations but his is the only one that I found that had documentation.

Even with simple code, best practices can still be applied to it; not introducing side-effects, type hinting, and so on.

Odd; I explicitly clicked on 'suggestion'.

Since this is not an issue that seriously affects Kata quality (as per your words it is merely a good idea), please re-open this as a Suggestion.

Thank you for your cooperation.

It would be a good idea to stick to PSR-2 for conventions in here, and add namespacing.

What is this sorcery?

whaat??

Clever:)