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// Copyright 2013 The Closure Library Authors. All Rights Reserved.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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//      http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS-IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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/**
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 * @fileoverview Utility to attempt native JSON processing, falling back to
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 *     goog.json if not available.
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 *
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 *     This is intended as a drop-in for current users of goog.json who want
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 *     to take advantage of native JSON if present.
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 *
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 * @author [email protected] (Nathan Naze)
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 */
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goog.provide('goog.json.hybrid');
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goog.require('goog.asserts');
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goog.require('goog.json');
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/**
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 * Attempts to serialize the JSON string natively, falling back to
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 * {@code goog.json.serialize} if unsuccessful.
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 * @param {!Object} obj JavaScript object to serialize to JSON.
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 * @return {string} Resulting JSON string.
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 */
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goog.json.hybrid.stringify =
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    goog.json.USE_NATIVE_JSON ? goog.global['JSON']['stringify'] : function(
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                                                                       obj) {
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      if (goog.global.JSON) {
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        try {
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          return goog.global.JSON.stringify(obj);
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        } catch (e) {
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          // Native serialization failed.  Fall through to retry with
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          // goog.json.serialize.
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        }
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      }
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      return goog.json.serialize(obj);
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    };
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/**
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 * Attempts to parse the JSON string natively, falling back to
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 * the supplied {@code fallbackParser} if unsuccessful.
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 * @param {string} jsonString JSON string to parse.
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 * @param {function(string):Object} fallbackParser Fallback JSON parser used
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 *     if native
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 * @return {!Object} Resulting JSON object.
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 * @private
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 */
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goog.json.hybrid.parse_ = function(jsonString, fallbackParser) {
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  if (goog.global.JSON) {
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    try {
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      var obj = goog.global.JSON.parse(jsonString);
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      goog.asserts.assertObject(obj);
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      return obj;
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    } catch (e) {
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      // Native parse failed.  Fall through to retry with goog.json.unsafeParse.
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    }
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  }
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  var obj = fallbackParser(jsonString);
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  goog.asserts.assert(obj);
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  return obj;
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};
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/**
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 * Attempts to parse the JSON string natively, falling back to
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 * {@code goog.json.parse} if unsuccessful.
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 * @param {string} jsonString JSON string to parse.
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 * @return {!Object} Resulting JSON object.
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 */
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goog.json.hybrid.parse =
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    goog.json.USE_NATIVE_JSON ? goog.global['JSON']['parse'] : function(
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                                                                   jsonString) {
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      return goog.json.hybrid.parse_(jsonString, goog.json.parse);
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    };
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/**
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 * Attempts to parse the JSON string natively, falling back to
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 * {@code goog.json.unsafeParse} if unsuccessful.
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 * @param {string} jsonString JSON string to parse.
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 * @return {!Object} Resulting JSON object.
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 */
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goog.json.hybrid.unsafeParse =
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    goog.json.USE_NATIVE_JSON ? goog.global['JSON']['parse'] : function(
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                                                                   jsonString) {
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      return goog.json.hybrid.parse_(jsonString, goog.json.unsafeParse);
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    };
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