//skip-idempotent import java.util.function.Consumer; import java.util.function.Function; class ExtensionMethodAmbiguousFunctional { public void test() { ExtensionMethodAmbiguousFunctional.Extensions.ambiguous("", System.out::println); } static class Extensions { public static void ambiguous(T t, Function function) { } public static void ambiguous(T t, Consumer function) { } } }