If two methods use same binding/relation annotation for a child element, then throw error at compile time

[GoogleCodeExporter]

If two methods use same binding/relation annotation for a child element, then 
throw error at compile time

for example:

    @Binding.Start("rule")
    public static Rule onRule(@Attr String name){
        ...
    }

    @Binding.Start("rule")
    public static Matcher onMatcher(@Attr String name){
        ...
    }

this should be caught at compile time. This type of mistakes quite often happen 
in copy paste.

Original issue reported on code.google.com by [email protected] on 10 Sep 2010 at 4:44