VeinFilter

What?

VeinFilter is an open-source back-port of the FoundationEssentials.Predicate and FoundationMacros.Predicate.

It's goals are to provide Predicate functionality starting at macOS v13 and iOS v14, because someone requested it for the Amethyst Vein DB Framework.

How?

It's based on the open-source swift-foundation. I copied the necessary files over, removed version constraints, renamed everything so it doesn't conflict with the real foundation and adjusted the implementation so it works with the older versions.

How to use it?

Add it to your project via SwiftPM and use it like you would use a #Predicate, just that this one and it's internals are called #Filter and alike.

Caveats

VeinFilter currently doesn't support all features the real predicate does. Missing are:

• #Expression and Expression as Vein doesn't need them and it would take additional effort to back-port (repeat and each keywords are used).
• .filter() and PredicateExpressions.Filter as Vein doesn't need them and it would take additional effort to back-port (repeat and each keywords are used).
• StringContainsRegex and the function as Vein (currently) doesn't need them and it would take additional effort to back-port (regex._literalPattern is only available starting macOS 15).

If you want to spend time and energy to support them, feel free to submit a PR.

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Have fun with Predicates on a slightly older version lol