KSP function processor, process function, visitor

FunctionProcessor.kt

class FunctionProcessor(...) : SymbolProcessor {

    override fun process(resolver: Resolver): List<KSAnnotated> {
        ...

        symbols.forEach { it.accept(Visitor(file), Unit) }

        file.close()
        val unableToProcess = symbols.filterNot { it.validate() }.toList()
        return unableToProcess
    }
}