Visitor1.kt

inner class Visitor : KSVisitorVoid() {
    
    override fun visitClassDeclaration(classDeclaration: KSClassDeclaration, data: Unit) {
        val qualifiedName = classDeclaration.qualifiedName?.asString()

        if (!classDeclaration.isDataClass()) {
            logger.error(
                "@IntSummable cannot target non-data class $qualifiedName",
                classDeclaration
            )
            return
        }

        if (qualifiedName == null) {
            logger.error(
                "@IntSummable must target classes with qualified names",
                classDeclaration
            )
            return
        }
    }
    
    private fun KSClassDeclaration.isDataClass() = modifiers.contains(Modifier.DATA)
}