https://issues.dlang.org/show_bug.cgi?id=21883

          Issue ID: 21883
           Summary: poor error message when swapping order of base class
                    and interface
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: minor
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: destructionator@gmail.com

module test;

interface InterfaceA {
    void method();
}

class ClassA {
    string somefield;
    void method2() {}
}

class ClassB: InterfaceA, ClassA { // unhelpful error message
    void method() {}
}

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