Compiler Error CS1107

A parameter can only have one 'modifier name' modifier.

It is an error for parameter modifiers such as this, ref, and out to appear more than one time in a parameter definition.

Example

The following example generates CS1107:

// cs1107.cs
public static class Test
{
    // Extension methods.
        public static void TestMethod(this this t) {} // CS1107

    // Regular Instance Method
        public void TestMethod(ref ref int i) {} // CS1107

}