feat(types): union types, intersection, DNF #199

[kakserpom]

Implements #199

[coveralls]

Pull Request Test Coverage Report for Build 20557543062

Details

• 42 of 421 (9.98%) changed or added relevant lines in 5 files are covered.
• 3 unchanged lines in 2 files lost coverage.
• Overall coverage decreased (-2.1%) to 33.693%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
crates/macros/src/impl_.rs	0	5	0.0%
src/args.rs	30	82	36.59%
src/zend/_type.rs	0	135	0.0%
crates/macros/src/function.rs	7	194	3.61%

Files with Coverage Reduction	New Missed Lines	%
crates/macros/src/impl_.rs	1	11.11%
src/args.rs	2	62.26%

Totals
Change from base Build 20556324797:	-2.1%
Covered Lines:	1841
Relevant Lines:	5464

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💛 - Coveralls

[Xenira]

We could probably represent union types as rust enums. Same for intersection types were all elements are traits.

But that is something we can consider for a later iteration.