Using an existing annotation as to trigger AST transformations. This sample compiles a class which is annotated with @entity, and we want to transparently apply @tostring(includeNames=true) to it.

ast_aliasing.groovy

import org.codehaus.groovy.control.CompilerConfiguration
import groovy.transform.ToString
import static org.codehaus.groovy.control.customizers.builder.CompilerCustomizationBuilder.*
import org.codehaus.groovy.control.customizers.ASTTransformationCustomizer

def cc = new CompilerConfiguration()
withConfig(cc) {
    inline(phase: 'CONVERSION') { source, context, classNode ->
       if (classNode.annotations.any { it.classNode.name == 'Entity' }) {
          new ASTTransformationCustomizer(ToString, includeNames:true).call(source, context, classNode)
       }
    }
}
def shell = new GroovyShell(cc)
shell.evaluate '''@interface Entity {}

@Entity
class Person {
   String name
   int age
}
new Person(name:'Bob', age: 40)
'''