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:   | Identifier 'as' Identifier
  ;
  
  exportDeclaration
    : Export '*' fromClause ';'?
    | Export namedImports fromClause? ';'?
    | Export variableStatement
    | Export functionDeclaration
    | Export lexicalDeclaration
    | Export Default functionDeclaration
    | Export Default singleExpression ';'?
  ;
  
  classDeclaration
    : Default? Class Identifier? classTail
  ;
  
  classTail
    : heritage? '{' classElement+ '}'
  ;
  
  heritage
    : Extends singleExpression
  ;
  
  classElement
    : Static? methodDefinition
  ;
  
  methodDefinition
    : propertyName '(' formalParameterList ')' '{' functionBody '}'
    | getter propertyName '(' ')' '{' functionBody '}'
    | setter propertyName '(' propertySetParameterList ')' '{' functionBody '}'
    | '*' propertyName '(' formalParameterList ')' '{' functionBody '}'
  ;
  
  /// Block :
  