anchor.diff:   | throwStatement
    | tryStatement
    | debuggerStatement
  - | importStatement
  - | exportStatement
  - | lexicalStatement
  - ;
  -
  -lexicalStatement
  -  : 'let' bindingList
  -  | 'const' bindingList
  +;
  +
  +lexicalDeclaration
  +  : Let bindingList
  +  | Const bindingList
   ;
   
   bindingList
  
positive.code:   : '...' Identifier
  ;
  
  importStatement
   : 'import' importClause fromClause ';'?
   | 'import' StringLiteral ';'?
  ;
  
  
  
negative.code: sourceElement
   : statement
   | functionDeclaration
   | importDeclaration
   | exportDeclaration
   | lexicalDeclaration
   | classDeclaration
   ;
  
  /// Statement :
  