@gmsoft/spel2js/src/ast/VariableReference.js

Parse Spring Expression Language in JavaScript

/*
 * Copyright 2002-2015 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import { SpelNode } from './SpelNode';

/**
 * Represents a variable reference, eg. #someVar. Note this is different to a *local*
 * variable like $someVar
 *
 * @author Andy Clement
 * @author Ben March
 * @since 0.2.0
 */

function createNode(variableName, position) {
  var node = SpelNode.create('variable', position);

  node.getValue = function (state) {
    var context = state.activeContext.peek(),
      locals = state.locals;

    if (!context) {
      throw {
        name: 'ContextDoesNotExistException',
        message: "Attempting to look up variable '" + variableName + "' for an undefined context.",
      };
    }

    //there are 2 keywords (root, this) that need to be dealt with
    if (variableName === 'this') {
      return context;
    }
    if (variableName === 'root') {
      return state.rootContext;
    }

    return locals[variableName];
  };

  node.setValue = function (value, state) {
    var locals = state.locals;

    /*jshint -W093 */
    return (locals[variableName] = value);
    /*jshint +W093 */
  };

  return node;
}

export var VariableReference = {
  create: createNode,
};