anchor.diff:  
   equalityExpression
       : comparisonExpression
  -      (('=='^|'!='^|'='^) comparisonExpression)?
  +      (('=='^|'!='^|'==='^) comparisonExpression)?
       ;
   
   comparisonExpression
  
positive.code:     ;
  
  formalParameterType
      : (type|'void') '...'?
      ;
  
  // Control structures.
  
negative.code: 
  compilationUnit
      : importDeclaration*
        ( (annotatedDeclarationStart) => toplevelDeclaration )+
        expression?
        EOF
      -> ^(IMPORT_LIST importDeclaration*)
  