anchor.diff:  options { tokenVocab = KotlinLexer; }
   
   kotlinFile
  -    : NL* fileAnnotation? packageHeader importList topLevelObject* EOF
  +    : NL* preamble topLevelObject* EOF
       ;
   
   script
  -    : NL* fileAnnotation? packageHeader importList(expression semi?)* EOF
  +    : NL* preamble expression* EOF
  +    ;
  +
  +preamble
  +    : fileAnnotations? packageHeader importList
  +    ;
  +
  +fileAnnotations
  +    : fileAnnotation+
       ;
   
   fileAnnotation
  
positive.code:     ;
  
  packageHeader
      : (PACKAGE identifier semi?)?
      ;
  
  importList
  
negative.code: 
  topLevelObject
      : (classDeclaration
      | objectDeclaration
      | functionDeclaration
      | propertyDeclaration
      | typeAlias) anysemi*
      ;
  
  classDeclaration
  