Hello, I want to implement compiler plugin, that c...

# compiler

[Tomasz Krakowiak]

Hello, I want to implement compiler plugin, that creates something like macro from annotated function. Something that would take something like:

fun styled(block : RuleSet, @CallerPackage packageName)

and introduce synthetic macro-like function:

fun styled(block : RuleSet) = styled(block, callerPackage())

and wherever styled(block) is used, plugin would replace calls with styled(block, "actual.callers.package.name") .

Are there any good examples I could use? Maybe somewhere in compose?

[shikasd]

It should be possible to implement this as an IR transform. You would need to find the symbol of styled (you can check how Compose finds Composer class, for example) and then run replace each IrCall which calls that function (using IrElementTransformer or similar). Package name can be retrieved from parent class or file (fqName property iirc)

Btw, I recommend using fun styled(block: RuleSet, packageName: String = throw IllegalArgumentException("Must be replaced at compile time"))
If it is called with default parameter, it will be easier to replace just one argument and not whole call (each function has different symbol and you'll have to replace it completely)

I don't have any examples atm (typing this from the mobile), but maybe someone will link similar transforms.

[raulraja]

Hi @Tomasz Krakowiak we do something similar in the proofs plugin in arrow meta. https://github.com/arrow-kt/arrow-meta/blob/main/plugins/proofs/proofs-plugin/src/main/kotlin/arrow/meta/plugins/proofs/phases/ir/ProofsIrCodegen.kt#L100 (parameter insertion after being resolved) https://github.com/arrow-kt/arrow-meta/blob/main/plugins/proofs/proofs-plugin/src/test/kotlin/arrow/meta/plugins/proofs/ContextTest.kt (some test examples that show implicit argument injection)