anchor.diff:      ;
   
   importElement
  -    : 'implicit'? importAlias? importedName
  -    -> ^(IMPORT_ELEM 'implicit'? importAlias? importedName)
  +    : IMPLICIT? importAlias? importedName
  +    -> ^(IMPORT_ELEM IMPLICIT? importAlias? importedName)
       ;
   
   importWildcard
  
positive.code:     ;
  
  existsCondition
      : 'exists' controlVariableOrExpression
      -> ^(EXISTS_EXPR controlVariableOrExpression)
      ;
      
  nonemptyCondition
      : 'nonempty' controlVariableOrExpression
      -> ^(NONEMPTY_EXPR controlVariableOrExpression)
      ;
  
  isCondition
      : 'is' type (memberName specifier | expression)
      -> ^(IS_EXPR type memberName? specifier? expression?)
      ;
  
  satisfiesCondition
      : 'satisfies' type type
      -> ^(SATISFIES_EXPR type type)
      ;
  
  controlStructure
  
negative.code:     POS_ARG_LIST;
      POSTFIX_EXPR;
      PRIMARY;
      SATISFIES_EXPR;
      SEQ_ARG;
      SPECIAL_ARG;
      TRY_CATCH_STMT;
      TRY_RESOURCE;
      TYPE_ARG_LIST;
      TYPE_DECL;
      TYPE_NAME;
      TYPE_PARAMETER_LIST;
      TYPE_SPECIFIER;
      WHILE_STMT;
      DO_WHILE_STMT;
      SWITCH_STMT;
      SWITCH_CASE_LIST;
      TYPE_CONSTRAINT_LIST;
      TYPE;
  