code: function isUsedFromOutsideOf(scopeNode) {
  
      /**
       * Checks whether a given reference is inside of the specified scope or not.
       *
       * @param {eslint-scope.Reference} reference - A reference to check.
       * @returns {boolean} `true` if the reference is inside of the specified
       *      scope.
       */
      function isOutsideOfScope(reference) {
          const scope = scopeNode.range;
          const id = reference.identifier.range;
  
          return id[0] < scope[0] || id[1] > scope[1];
      }
  
      return function(variable) {
          return variable.references.some(isOutsideOfScope);
      };
  }
docs: Checks whether a given variable is used from outside of the specified scope.
  
  @param {ASTNode} scopeNode - A scope node to check.
  @returns {Function} The predicate function which checks whether a given
  variable is used from outside of the specified scope.