anchor.diff:  
   definition
   	: callbackOrInterfaceOrMixin
  -	| namespace
  +	| namespace_
   	| partial
   	| dictionary
   	| enum_
  
positive.code: 	: 'setlike' '<' typeWithExtendedAttributes '>' ';'
  ;
  
  namespace
      : 'namespace' IDENTIFIER_WEBIDL '{' namespaceMembers '}' ';'
  ;
  
  
negative.code: partialDefinition
  	: 'interface' partialInterfaceOrPartialMixin
  	| partialDictionary
  	| namespace_
  ;
  
  partialInterfaceOrPartialMixin
  