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Posted to commits@brooklyn.apache.org by he...@apache.org on 2016/02/08 12:11:58 UTC

[02/11] brooklyn-ui git commit: Replace existing textareas for editing YAML with Composer Tab + Codemirror

http://git-wip-us.apache.org/repos/asf/brooklyn-ui/blob/4174bdb2/src/main/webapp/assets/js/libs/js-yaml.js
----------------------------------------------------------------------
diff --git a/src/main/webapp/assets/js/libs/js-yaml.js b/src/main/webapp/assets/js/libs/js-yaml.js
index 890b00e..fbc53e6 100644
--- a/src/main/webapp/assets/js/libs/js-yaml.js
+++ b/src/main/webapp/assets/js/libs/js-yaml.js
@@ -1,872 +1,1188 @@
-/* js-yaml 3.2.7 https://github.com/nodeca/js-yaml */!function(e){if("object"==typeof exports&&"undefined"!=typeof module)module.exports=e();else if("function"==typeof define&&define.amd)define([],e);else{var f;"undefined"!=typeof window?f=window:"undefined"!=typeof global?f=global:"undefined"!=typeof self&&(f=self),f.jsyaml=e()}}(function(){var define,module,exports;return (function e(t,n,r){function s(o,u){if(!n[o]){if(!t[o]){var a=typeof require=="function"&&require;if(!u&&a)return a(o,!0);if(i)return i(o,!0);var f=new Error("Cannot find module '"+o+"'");throw f.code="MODULE_NOT_FOUND",f}var l=n[o]={exports:{}};t[o][0].call(l.exports,function(e){var n=t[o][1][e];return s(n?n:e)},l,l.exports,e,t,n,r)}return n[o].exports}var i=typeof require=="function"&&require;for(var o=0;o<r.length;o++)s(r[o]);return s})({1:[function(require,module,exports){
-'use strict';
+/* js-yaml 3.5.2 https://github.com/nodeca/js-yaml */(function(f){if(typeof exports==="object"&&typeof module!=="undefined"){module.exports=f()}else if(typeof define==="function"&&define.amd){define([],f)}else{var g;if(typeof window!=="undefined"){g=window}else if(typeof global!=="undefined"){g=global}else if(typeof self!=="undefined"){g=self}else{g=this}g.jsyaml = f()}})(function(){var define,module,exports;return (function e(t,n,r){function s(o,u){if(!n[o]){if(!t[o]){var a=typeof require=="function"&&require;if(!u&&a)return a(o,!0);if(i)return i(o,!0);var f=new Error("Cannot find module '"+o+"'");throw f.code="MODULE_NOT_FOUND",f}var l=n[o]={exports:{}};t[o][0].call(l.exports,function(e){var n=t[o][1][e];return s(n?n:e)},l,l.exports,e,t,n,r)}return n[o].exports}var i=typeof require=="function"&&require;for(var o=0;o<r.length;o++)s(r[o]);return s})({1:[function(require,module,exports){
+  'use strict';
 
 
-var loader = require('./js-yaml/loader');
-var dumper = require('./js-yaml/dumper');
+  var loader = require('./js-yaml/loader');
+  var dumper = require('./js-yaml/dumper');
 
 
-function deprecated(name) {
-  return function () {
-    throw new Error('Function ' + name + ' is deprecated and cannot be used.');
-  };
-}
-
-
-module.exports.Type                = require('./js-yaml/type');
-module.exports.Schema              = require('./js-yaml/schema');
-module.exports.FAILSAFE_SCHEMA     = require('./js-yaml/schema/failsafe');
-module.exports.JSON_SCHEMA         = require('./js-yaml/schema/json');
-module.exports.CORE_SCHEMA         = require('./js-yaml/schema/core');
-module.exports.DEFAULT_SAFE_SCHEMA = require('./js-yaml/schema/default_safe');
-module.exports.DEFAULT_FULL_SCHEMA = require('./js-yaml/schema/default_full');
-module.exports.load                = loader.load;
-module.exports.loadAll             = loader.loadAll;
-module.exports.safeLoad            = loader.safeLoad;
-module.exports.safeLoadAll         = loader.safeLoadAll;
-module.exports.dump                = dumper.dump;
-module.exports.safeDump            = dumper.safeDump;
-module.exports.YAMLException       = require('./js-yaml/exception');
-
-// Deprecared schema names from JS-YAML 2.0.x
-module.exports.MINIMAL_SCHEMA = require('./js-yaml/schema/failsafe');
-module.exports.SAFE_SCHEMA    = require('./js-yaml/schema/default_safe');
-module.exports.DEFAULT_SCHEMA = require('./js-yaml/schema/default_full');
+  function deprecated(name) {
+    return function () {
+      throw new Error('Function ' + name + ' is deprecated and cannot be used.');
+    };
+  }
+
+
+  module.exports.Type                = require('./js-yaml/type');
+  module.exports.Schema              = require('./js-yaml/schema');
+  module.exports.FAILSAFE_SCHEMA     = require('./js-yaml/schema/failsafe');
+  module.exports.JSON_SCHEMA         = require('./js-yaml/schema/json');
+  module.exports.CORE_SCHEMA         = require('./js-yaml/schema/core');
+  module.exports.DEFAULT_SAFE_SCHEMA = require('./js-yaml/schema/default_safe');
+  module.exports.DEFAULT_FULL_SCHEMA = require('./js-yaml/schema/default_full');
+  module.exports.load                = loader.load;
+  module.exports.loadAll             = loader.loadAll;
+  module.exports.safeLoad            = loader.safeLoad;
+  module.exports.safeLoadAll         = loader.safeLoadAll;
+  module.exports.dump                = dumper.dump;
+  module.exports.safeDump            = dumper.safeDump;
+  module.exports.YAMLException       = require('./js-yaml/exception');
+
+// Deprecated schema names from JS-YAML 2.0.x
+  module.exports.MINIMAL_SCHEMA = require('./js-yaml/schema/failsafe');
+  module.exports.SAFE_SCHEMA    = require('./js-yaml/schema/default_safe');
+  module.exports.DEFAULT_SCHEMA = require('./js-yaml/schema/default_full');
 
 // Deprecated functions from JS-YAML 1.x.x
-module.exports.scan           = deprecated('scan');
-module.exports.parse          = deprecated('parse');
-module.exports.compose        = deprecated('compose');
-module.exports.addConstructor = deprecated('addConstructor');
+  module.exports.scan           = deprecated('scan');
+  module.exports.parse          = deprecated('parse');
+  module.exports.compose        = deprecated('compose');
+  module.exports.addConstructor = deprecated('addConstructor');
 
 },{"./js-yaml/dumper":3,"./js-yaml/exception":4,"./js-yaml/loader":5,"./js-yaml/schema":7,"./js-yaml/schema/core":8,"./js-yaml/schema/default_full":9,"./js-yaml/schema/default_safe":10,"./js-yaml/schema/failsafe":11,"./js-yaml/schema/json":12,"./js-yaml/type":13}],2:[function(require,module,exports){
-'use strict';
+  'use strict';
 
 
-function isNothing(subject) {
-  return (undefined === subject) || (null === subject);
-}
+  function isNothing(subject) {
+    return (typeof subject === 'undefined') || (null === subject);
+  }
 
 
-function isObject(subject) {
-  return ('object' === typeof subject) && (null !== subject);
-}
+  function isObject(subject) {
+    return (typeof subject === 'object') && (null !== subject);
+  }
 
 
-function toArray(sequence) {
-  if (Array.isArray(sequence)) {
-    return sequence;
-  } else if (isNothing(sequence)) {
-    return [];
-  } else {
+  function toArray(sequence) {
+    if (Array.isArray(sequence)) {
+      return sequence;
+    } else if (isNothing(sequence)) {
+      return [];
+    }
     return [ sequence ];
   }
-}
 
 
-function extend(target, source) {
-  var index, length, key, sourceKeys;
+  function extend(target, source) {
+    var index, length, key, sourceKeys;
 
-  if (source) {
-    sourceKeys = Object.keys(source);
+    if (source) {
+      sourceKeys = Object.keys(source);
 
-    for (index = 0, length = sourceKeys.length; index < length; index += 1) {
-      key = sourceKeys[index];
-      target[key] = source[key];
+      for (index = 0, length = sourceKeys.length; index < length; index += 1) {
+        key = sourceKeys[index];
+        target[key] = source[key];
+      }
     }
+
+    return target;
   }
 
-  return target;
-}
 
+  function repeat(string, count) {
+    var result = '', cycle;
 
-function repeat(string, count) {
-  var result = '', cycle;
+    for (cycle = 0; cycle < count; cycle += 1) {
+      result += string;
+    }
 
-  for (cycle = 0; cycle < count; cycle += 1) {
-    result += string;
+    return result;
   }
 
-  return result;
-}
-
 
-function isNegativeZero(number) {
-  return (0 === number) && (Number.NEGATIVE_INFINITY === 1 / number);
-}
+  function isNegativeZero(number) {
+    return (0 === number) && (Number.NEGATIVE_INFINITY === 1 / number);
+  }
 
 
-module.exports.isNothing      = isNothing;
-module.exports.isObject       = isObject;
-module.exports.toArray        = toArray;
-module.exports.repeat         = repeat;
-module.exports.isNegativeZero = isNegativeZero;
-module.exports.extend         = extend;
+  module.exports.isNothing      = isNothing;
+  module.exports.isObject       = isObject;
+  module.exports.toArray        = toArray;
+  module.exports.repeat         = repeat;
+  module.exports.isNegativeZero = isNegativeZero;
+  module.exports.extend         = extend;
 
 },{}],3:[function(require,module,exports){
-'use strict';
+  'use strict';
+
+  /*eslint-disable no-use-before-define*/
+
+  var common              = require('./common');
+  var YAMLException       = require('./exception');
+  var DEFAULT_FULL_SCHEMA = require('./schema/default_full');
+  var DEFAULT_SAFE_SCHEMA = require('./schema/default_safe');
+
+  var _toString       = Object.prototype.toString;
+  var _hasOwnProperty = Object.prototype.hasOwnProperty;
+
+  var CHAR_TAB                  = 0x09; /* Tab */
+  var CHAR_LINE_FEED            = 0x0A; /* LF */
+  var CHAR_CARRIAGE_RETURN      = 0x0D; /* CR */
+  var CHAR_SPACE                = 0x20; /* Space */
+  var CHAR_EXCLAMATION          = 0x21; /* ! */
+  var CHAR_DOUBLE_QUOTE         = 0x22; /* " */
+  var CHAR_SHARP                = 0x23; /* # */
+  var CHAR_PERCENT              = 0x25; /* % */
+  var CHAR_AMPERSAND            = 0x26; /* & */
+  var CHAR_SINGLE_QUOTE         = 0x27; /* ' */
+  var CHAR_ASTERISK             = 0x2A; /* * */
+  var CHAR_COMMA                = 0x2C; /* , */
+  var CHAR_MINUS                = 0x2D; /* - */
+  var CHAR_COLON                = 0x3A; /* : */
+  var CHAR_GREATER_THAN         = 0x3E; /* > */
+  var CHAR_QUESTION             = 0x3F; /* ? */
+  var CHAR_COMMERCIAL_AT        = 0x40; /* @ */
+  var CHAR_LEFT_SQUARE_BRACKET  = 0x5B; /* [ */
+  var CHAR_RIGHT_SQUARE_BRACKET = 0x5D; /* ] */
+  var CHAR_GRAVE_ACCENT         = 0x60; /* ` */
+  var CHAR_LEFT_CURLY_BRACKET   = 0x7B; /* { */
+  var CHAR_VERTICAL_LINE        = 0x7C; /* | */
+  var CHAR_RIGHT_CURLY_BRACKET  = 0x7D; /* } */
+
+  var ESCAPE_SEQUENCES = {};
+
+  ESCAPE_SEQUENCES[0x00]   = '\\0';
+  ESCAPE_SEQUENCES[0x07]   = '\\a';
+  ESCAPE_SEQUENCES[0x08]   = '\\b';
+  ESCAPE_SEQUENCES[0x09]   = '\\t';
+  ESCAPE_SEQUENCES[0x0A]   = '\\n';
+  ESCAPE_SEQUENCES[0x0B]   = '\\v';
+  ESCAPE_SEQUENCES[0x0C]   = '\\f';
+  ESCAPE_SEQUENCES[0x0D]   = '\\r';
+  ESCAPE_SEQUENCES[0x1B]   = '\\e';
+  ESCAPE_SEQUENCES[0x22]   = '\\"';
+  ESCAPE_SEQUENCES[0x5C]   = '\\\\';
+  ESCAPE_SEQUENCES[0x85]   = '\\N';
+  ESCAPE_SEQUENCES[0xA0]   = '\\_';
+  ESCAPE_SEQUENCES[0x2028] = '\\L';
+  ESCAPE_SEQUENCES[0x2029] = '\\P';
+
+  var DEPRECATED_BOOLEANS_SYNTAX = [
+    'y', 'Y', 'yes', 'Yes', 'YES', 'on', 'On', 'ON',
+    'n', 'N', 'no', 'No', 'NO', 'off', 'Off', 'OFF'
+  ];
+
+  function compileStyleMap(schema, map) {
+    var result, keys, index, length, tag, style, type;
+
+    if (null === map) {
+      return {};
+    }
+
+    result = {};
+    keys = Object.keys(map);
+
+    for (index = 0, length = keys.length; index < length; index += 1) {
+      tag = keys[index];
+      style = String(map[tag]);
+
+      if ('!!' === tag.slice(0, 2)) {
+        tag = 'tag:yaml.org,2002:' + tag.slice(2);
+      }
 
+      type = schema.compiledTypeMap[tag];
 
-var common              = require('./common');
-var YAMLException       = require('./exception');
-var DEFAULT_FULL_SCHEMA = require('./schema/default_full');
-var DEFAULT_SAFE_SCHEMA = require('./schema/default_safe');
+      if (type && _hasOwnProperty.call(type.styleAliases, style)) {
+        style = type.styleAliases[style];
+      }
 
+      result[tag] = style;
+    }
 
-var _toString       = Object.prototype.toString;
-var _hasOwnProperty = Object.prototype.hasOwnProperty;
+    return result;
+  }
 
+  function encodeHex(character) {
+    var string, handle, length;
 
-var CHAR_TAB                  = 0x09; /* Tab */
-var CHAR_LINE_FEED            = 0x0A; /* LF */
-var CHAR_CARRIAGE_RETURN      = 0x0D; /* CR */
-var CHAR_SPACE                = 0x20; /* Space */
-var CHAR_EXCLAMATION          = 0x21; /* ! */
-var CHAR_DOUBLE_QUOTE         = 0x22; /* " */
-var CHAR_SHARP                = 0x23; /* # */
-var CHAR_PERCENT              = 0x25; /* % */
-var CHAR_AMPERSAND            = 0x26; /* & */
-var CHAR_SINGLE_QUOTE         = 0x27; /* ' */
-var CHAR_ASTERISK             = 0x2A; /* * */
-var CHAR_COMMA                = 0x2C; /* , */
-var CHAR_MINUS                = 0x2D; /* - */
-var CHAR_COLON                = 0x3A; /* : */
-var CHAR_GREATER_THAN         = 0x3E; /* > */
-var CHAR_QUESTION             = 0x3F; /* ? */
-var CHAR_COMMERCIAL_AT        = 0x40; /* @ */
-var CHAR_LEFT_SQUARE_BRACKET  = 0x5B; /* [ */
-var CHAR_RIGHT_SQUARE_BRACKET = 0x5D; /* ] */
-var CHAR_GRAVE_ACCENT         = 0x60; /* ` */
-var CHAR_LEFT_CURLY_BRACKET   = 0x7B; /* { */
-var CHAR_VERTICAL_LINE        = 0x7C; /* | */
-var CHAR_RIGHT_CURLY_BRACKET  = 0x7D; /* } */
+    string = character.toString(16).toUpperCase();
 
+    if (character <= 0xFF) {
+      handle = 'x';
+      length = 2;
+    } else if (character <= 0xFFFF) {
+      handle = 'u';
+      length = 4;
+    } else if (character <= 0xFFFFFFFF) {
+      handle = 'U';
+      length = 8;
+    } else {
+      throw new YAMLException('code point within a string may not be greater than 0xFFFFFFFF');
+    }
 
-var ESCAPE_SEQUENCES = {};
+    return '\\' + handle + common.repeat('0', length - string.length) + string;
+  }
 
-ESCAPE_SEQUENCES[0x00]   = '\\0';
-ESCAPE_SEQUENCES[0x07]   = '\\a';
-ESCAPE_SEQUENCES[0x08]   = '\\b';
-ESCAPE_SEQUENCES[0x09]   = '\\t';
-ESCAPE_SEQUENCES[0x0A]   = '\\n';
-ESCAPE_SEQUENCES[0x0B]   = '\\v';
-ESCAPE_SEQUENCES[0x0C]   = '\\f';
-ESCAPE_SEQUENCES[0x0D]   = '\\r';
-ESCAPE_SEQUENCES[0x1B]   = '\\e';
-ESCAPE_SEQUENCES[0x22]   = '\\"';
-ESCAPE_SEQUENCES[0x5C]   = '\\\\';
-ESCAPE_SEQUENCES[0x85]   = '\\N';
-ESCAPE_SEQUENCES[0xA0]   = '\\_';
-ESCAPE_SEQUENCES[0x2028] = '\\L';
-ESCAPE_SEQUENCES[0x2029] = '\\P';
+  function State(options) {
+    this.schema      = options['schema'] || DEFAULT_FULL_SCHEMA;
+    this.indent      = Math.max(1, (options['indent'] || 2));
+    this.skipInvalid = options['skipInvalid'] || false;
+    this.flowLevel   = (common.isNothing(options['flowLevel']) ? -1 : options['flowLevel']);
+    this.styleMap    = compileStyleMap(this.schema, options['styles'] || null);
+    this.sortKeys    = options['sortKeys'] || false;
+    this.lineWidth   = options['lineWidth'] || 80;
+    this.noRefs      = options['noRefs'] || false;
 
+    this.implicitTypes = this.schema.compiledImplicit;
+    this.explicitTypes = this.schema.compiledExplicit;
 
-var DEPRECATED_BOOLEANS_SYNTAX = [
-  'y', 'Y', 'yes', 'Yes', 'YES', 'on', 'On', 'ON',
-  'n', 'N', 'no', 'No', 'NO', 'off', 'Off', 'OFF'
-];
+    this.tag = null;
+    this.result = '';
 
+    this.duplicates = [];
+    this.usedDuplicates = null;
+  }
 
-function compileStyleMap(schema, map) {
-  var result, keys, index, length, tag, style, type;
+  function indentString(string, spaces) {
+    var ind = common.repeat(' ', spaces),
+        position = 0,
+        next = -1,
+        result = '',
+        line,
+        length = string.length;
 
-  if (null === map) {
-    return {};
-  }
+    while (position < length) {
+      next = string.indexOf('\n', position);
+      if (next === -1) {
+        line = string.slice(position);
+        position = length;
+      } else {
+        line = string.slice(position, next + 1);
+        position = next + 1;
+      }
+      if (line.length && line !== '\n') {
+        result += ind;
+      }
+      result += line;
+    }
 
-  result = {};
-  keys = Object.keys(map);
+    return result;
+  }
 
-  for (index = 0, length = keys.length; index < length; index += 1) {
-    tag = keys[index];
-    style = String(map[tag]);
+  function generateNextLine(state, level) {
+    return '\n' + common.repeat(' ', state.indent * level);
+  }
 
-    if ('!!' === tag.slice(0, 2)) {
-      tag = 'tag:yaml.org,2002:' + tag.slice(2);
-    }
+  function testImplicitResolving(state, str) {
+    var index, length, type;
 
-    type = schema.compiledTypeMap[tag];
+    for (index = 0, length = state.implicitTypes.length; index < length; index += 1) {
+      type = state.implicitTypes[index];
 
-    if (type && _hasOwnProperty.call(type.styleAliases, style)) {
-      style = type.styleAliases[style];
+      if (type.resolve(str)) {
+        return true;
+      }
     }
 
-    result[tag] = style;
+    return false;
   }
 
-  return result;
-}
+  function StringBuilder(source) {
+    this.source = source;
+    this.result = '';
+    this.checkpoint = 0;
+  }
 
+  StringBuilder.prototype.takeUpTo = function (position) {
+    var er;
 
-function encodeHex(character) {
-  var string, handle, length;
+    if (position < this.checkpoint) {
+      er = new Error('position should be > checkpoint');
+      er.position = position;
+      er.checkpoint = this.checkpoint;
+      throw er;
+    }
 
-  string = character.toString(16).toUpperCase();
+    this.result += this.source.slice(this.checkpoint, position);
+    this.checkpoint = position;
+    return this;
+  };
 
-  if (character <= 0xFF) {
-    handle = 'x';
-    length = 2;
-  } else if (character <= 0xFFFF) {
-    handle = 'u';
-    length = 4;
-  } else if (character <= 0xFFFFFFFF) {
-    handle = 'U';
-    length = 8;
-  } else {
-    throw new YAMLException('code point within a string may not be greater than 0xFFFFFFFF');
-  }
+  StringBuilder.prototype.escapeChar = function () {
+    var character, esc;
 
-  return '\\' + handle + common.repeat('0', length - string.length) + string;
-}
+    character = this.source.charCodeAt(this.checkpoint);
+    esc = ESCAPE_SEQUENCES[character] || encodeHex(character);
+    this.result += esc;
+    this.checkpoint += 1;
 
+    return this;
+  };
 
-function State(options) {
-  this.schema      = options['schema'] || DEFAULT_FULL_SCHEMA;
-  this.indent      = Math.max(1, (options['indent'] || 2));
-  this.skipInvalid = options['skipInvalid'] || false;
-  this.flowLevel   = (common.isNothing(options['flowLevel']) ? -1 : options['flowLevel']);
-  this.styleMap    = compileStyleMap(this.schema, options['styles'] || null);
+  StringBuilder.prototype.finish = function () {
+    if (this.source.length > this.checkpoint) {
+      this.takeUpTo(this.source.length);
+    }
+  };
 
-  this.implicitTypes = this.schema.compiledImplicit;
-  this.explicitTypes = this.schema.compiledExplicit;
+  function writeScalar(state, object, level, iskey) {
+    var simple, first, spaceWrap, folded, literal, single, double,
+        sawLineFeed, linePosition, longestLine, indent, max, character,
+        position, escapeSeq, hexEsc, previous, lineLength, modifier,
+        trailingLineBreaks, result;
 
-  this.tag = null;
-  this.result = '';
+    if (0 === object.length) {
+      state.dump = "''";
+      return;
+    }
 
-  this.duplicates = [];
-  this.usedDuplicates = null;
-}
+    if (-1 !== DEPRECATED_BOOLEANS_SYNTAX.indexOf(object)) {
+      state.dump = "'" + object + "'";
+      return;
+    }
 
+    simple = true;
+    first = object.length ? object.charCodeAt(0) : 0;
+    spaceWrap = (CHAR_SPACE === first ||
+    CHAR_SPACE === object.charCodeAt(object.length - 1));
 
-function generateNextLine(state, level) {
-  return '\n' + common.repeat(' ', state.indent * level);
-}
+    // Simplified check for restricted first characters
+    // http://www.yaml.org/spec/1.2/spec.html#ns-plain-first%28c%29
+    if (CHAR_MINUS         === first ||
+        CHAR_QUESTION      === first ||
+        CHAR_COMMERCIAL_AT === first ||
+        CHAR_GRAVE_ACCENT  === first) {
+      simple = false;
+    }
 
-function testImplicitResolving(state, str) {
-  var index, length, type;
+    // Can only use > and | if not wrapped in spaces or is not a key.
+    // Also, don't use if in flow mode.
+    if (spaceWrap || (state.flowLevel > -1 && state.flowLevel <= level)) {
+      if (spaceWrap) {
+        simple = false;
+      }
+      folded = false;
+      literal = false;
+    } else {
+      folded = !iskey;
+      literal = !iskey;
+    }
 
-  for (index = 0, length = state.implicitTypes.length; index < length; index += 1) {
-    type = state.implicitTypes[index];
+    single = true;
+    double = new StringBuilder(object);
 
-    if (type.resolve(str)) {
-      return true;
+    sawLineFeed = false;
+    linePosition = 0;
+    longestLine = 0;
+
+    indent = state.indent * level;
+    max = state.lineWidth;
+    if (max === -1) {
+      // Replace -1 with biggest ingeger number according to
+      // http://ecma262-5.com/ELS5_HTML.htm#Section_8.5
+      max = 9007199254740991;
     }
-  }
 
-  return false;
-}
-
-function writeScalar(state, object) {
-  var isQuoted, checkpoint, position, length, character, first;
-
-  state.dump = '';
-  isQuoted = false;
-  checkpoint = 0;
-  first = object.charCodeAt(0) || 0;
-
-  if (-1 !== DEPRECATED_BOOLEANS_SYNTAX.indexOf(object)) {
-    // Ensure compatibility with YAML 1.0/1.1 loaders.
-    isQuoted = true;
-  } else if (0 === object.length) {
-    // Quote empty string
-    isQuoted = true;
-  } else if (CHAR_SPACE    === first ||
-             CHAR_SPACE    === object.charCodeAt(object.length - 1)) {
-    isQuoted = true;
-  } else if (CHAR_MINUS    === first ||
-             CHAR_QUESTION === first) {
-    // Don't check second symbol for simplicity
-    isQuoted = true;
-  }
-
-  for (position = 0, length = object.length; position < length; position += 1) {
-    character = object.charCodeAt(position);
-
-    if (!isQuoted) {
-      if (CHAR_TAB                  === character ||
-          CHAR_LINE_FEED            === character ||
-          CHAR_CARRIAGE_RETURN      === character ||
-          CHAR_COMMA                === character ||
-          CHAR_LEFT_SQUARE_BRACKET  === character ||
-          CHAR_RIGHT_SQUARE_BRACKET === character ||
-          CHAR_LEFT_CURLY_BRACKET   === character ||
-          CHAR_RIGHT_CURLY_BRACKET  === character ||
-          CHAR_SHARP                === character ||
-          CHAR_AMPERSAND            === character ||
-          CHAR_ASTERISK             === character ||
-          CHAR_EXCLAMATION          === character ||
-          CHAR_VERTICAL_LINE        === character ||
-          CHAR_GREATER_THAN         === character ||
-          CHAR_SINGLE_QUOTE         === character ||
-          CHAR_DOUBLE_QUOTE         === character ||
-          CHAR_PERCENT              === character ||
-          CHAR_COMMERCIAL_AT        === character ||
-          CHAR_COLON                === character ||
-          CHAR_GRAVE_ACCENT         === character) {
-        isQuoted = true;
-      }
-    }
-
-    if (ESCAPE_SEQUENCES[character] ||
-        !((0x00020 <= character && character <= 0x00007E) ||
-          (0x00085 === character)                         ||
-          (0x000A0 <= character && character <= 0x00D7FF) ||
-          (0x0E000 <= character && character <= 0x00FFFD) ||
-          (0x10000 <= character && character <= 0x10FFFF))) {
-      state.dump += object.slice(checkpoint, position);
-      state.dump += ESCAPE_SEQUENCES[character] || encodeHex(character);
-      checkpoint = position + 1;
-      isQuoted = true;
-    }
-  }
-
-  if (checkpoint < position) {
-    state.dump += object.slice(checkpoint, position);
-  }
-
-  if (!isQuoted && testImplicitResolving(state, state.dump)) {
-    isQuoted = true;
-  }
-
-  if (isQuoted) {
-    state.dump = '"' + state.dump + '"';
-  }
-}
-
-function writeFlowSequence(state, level, object) {
-  var _result = '',
-      _tag    = state.tag,
-      index,
-      length;
-
-  for (index = 0, length = object.length; index < length; index += 1) {
-    // Write only valid elements.
-    if (writeNode(state, level, object[index], false, false)) {
-      if (0 !== index) {
-        _result += ', ';
-      }
-      _result += state.dump;
+    if (indent < 40) {
+      max -= indent;
+    } else {
+      max = 40;
     }
-  }
 
-  state.tag = _tag;
-  state.dump = '[' + _result + ']';
-}
+    for (position = 0; position < object.length; position++) {
+      character = object.charCodeAt(position);
+      if (simple) {
+        // Characters that can never appear in the simple scalar
+        if (!simpleChar(character)) {
+          simple = false;
+        } else {
+          // Still simple.  If we make it all the way through like
+          // this, then we can just dump the string as-is.
+          continue;
+        }
+      }
+
+      if (single && character === CHAR_SINGLE_QUOTE) {
+        single = false;
+      }
 
-function writeBlockSequence(state, level, object, compact) {
-  var _result = '',
-      _tag    = state.tag,
-      index,
-      length;
+      escapeSeq = ESCAPE_SEQUENCES[character];
+      hexEsc = needsHexEscape(character);
 
-  for (index = 0, length = object.length; index < length; index += 1) {
-    // Write only valid elements.
-    if (writeNode(state, level + 1, object[index], true, true)) {
-      if (!compact || 0 !== index) {
-        _result += generateNextLine(state, level);
+      if (!escapeSeq && !hexEsc) {
+        continue;
       }
-      _result += '- ' + state.dump;
-    }
-  }
 
-  state.tag = _tag;
-  state.dump = _result || '[]'; // Empty sequence if no valid values.
-}
+      if (character !== CHAR_LINE_FEED &&
+          character !== CHAR_DOUBLE_QUOTE &&
+          character !== CHAR_SINGLE_QUOTE) {
+        folded = false;
+        literal = false;
+      } else if (character === CHAR_LINE_FEED) {
+        sawLineFeed = true;
+        single = false;
+        if (position > 0) {
+          previous = object.charCodeAt(position - 1);
+          if (previous === CHAR_SPACE) {
+            literal = false;
+            folded = false;
+          }
+        }
+        if (folded) {
+          lineLength = position - linePosition;
+          linePosition = position;
+          if (lineLength > longestLine) {
+            longestLine = lineLength;
+          }
+        }
+      }
 
-function writeFlowMapping(state, level, object) {
-  var _result       = '',
-      _tag          = state.tag,
-      objectKeyList = Object.keys(object),
-      index,
-      length,
-      objectKey,
-      objectValue,
-      pairBuffer;
+      if (character !== CHAR_DOUBLE_QUOTE) {
+        single = false;
+      }
 
-  for (index = 0, length = objectKeyList.length; index < length; index += 1) {
-    pairBuffer = '';
+      double.takeUpTo(position);
+      double.escapeChar();
+    }
 
-    if (0 !== index) {
-      pairBuffer += ', ';
+    if (simple && testImplicitResolving(state, object)) {
+      simple = false;
     }
 
-    objectKey = objectKeyList[index];
-    objectValue = object[objectKey];
+    modifier = '';
+    if (folded || literal) {
+      trailingLineBreaks = 0;
+      if (object.charCodeAt(object.length - 1) === CHAR_LINE_FEED) {
+        trailingLineBreaks += 1;
+        if (object.charCodeAt(object.length - 2) === CHAR_LINE_FEED) {
+          trailingLineBreaks += 1;
+        }
+      }
 
-    if (!writeNode(state, level, objectKey, false, false)) {
-      continue; // Skip this pair because of invalid key;
+      if (trailingLineBreaks === 0) {
+        modifier = '-';
+      } else if (trailingLineBreaks === 2) {
+        modifier = '+';
+      }
     }
 
-    if (state.dump.length > 1024) {
-      pairBuffer += '? ';
+    if (literal && longestLine < max || state.tag !== null) {
+      folded = false;
     }
 
-    pairBuffer += state.dump + ': ';
+    // If it's literally one line, then don't bother with the literal.
+    // We may still want to do a fold, though, if it's a super long line.
+    if (!sawLineFeed) {
+      literal = false;
+    }
 
-    if (!writeNode(state, level, objectValue, false, false)) {
-      continue; // Skip this pair because of invalid value.
+    if (simple) {
+      state.dump = object;
+    } else if (single) {
+      state.dump = '\'' + object + '\'';
+    } else if (folded) {
+      result = fold(object, max);
+      state.dump = '>' + modifier + '\n' + indentString(result, indent);
+    } else if (literal) {
+      if (!modifier) {
+        object = object.replace(/\n$/, '');
+      }
+      state.dump = '|' + modifier + '\n' + indentString(object, indent);
+    } else if (double) {
+      double.finish();
+      state.dump = '"' + double.result + '"';
+    } else {
+      throw new Error('Failed to dump scalar value');
     }
 
-    pairBuffer += state.dump;
+    return;
+  }
+
+// The `trailing` var is a regexp match of any trailing `\n` characters.
+//
+// There are three cases we care about:
+//
+// 1. One trailing `\n` on the string.  Just use `|` or `>`.
+//    This is the assumed default. (trailing = null)
+// 2. No trailing `\n` on the string.  Use `|-` or `>-` to "chomp" the end.
+// 3. More than one trailing `\n` on the string.  Use `|+` or `>+`.
+//
+// In the case of `>+`, these line breaks are *not* doubled (like the line
+// breaks within the string), so it's important to only end with the exact
+// same number as we started.
+  function fold(object, max) {
+    var result = '',
+        position = 0,
+        length = object.length,
+        trailing = /\n+$/.exec(object),
+        newLine;
+
+    if (trailing) {
+      length = trailing.index + 1;
+    }
+
+    while (position < length) {
+      newLine = object.indexOf('\n', position);
+      if (newLine > length || newLine === -1) {
+        if (result) {
+          result += '\n\n';
+        }
+        result += foldLine(object.slice(position, length), max);
+        position = length;
+      } else {
+        if (result) {
+          result += '\n\n';
+        }
+        result += foldLine(object.slice(position, newLine), max);
+        position = newLine + 1;
+      }
+    }
+    if (trailing && trailing[0] !== '\n') {
+      result += trailing[0];
+    }
 
-    // Both key and value are valid.
-    _result += pairBuffer;
+    return result;
   }
 
-  state.tag = _tag;
-  state.dump = '{' + _result + '}';
-}
+  function foldLine(line, max) {
+    if (line === '') {
+      return line;
+    }
+
+    var foldRe = /[^\s] [^\s]/g,
+        result = '',
+        prevMatch = 0,
+        foldStart = 0,
+        match = foldRe.exec(line),
+        index,
+        foldEnd,
+        folded;
 
-function writeBlockMapping(state, level, object, compact) {
-  var _result       = '',
-      _tag          = state.tag,
-      objectKeyList = Object.keys(object),
-      index,
-      length,
-      objectKey,
-      objectValue,
-      explicitPair,
-      pairBuffer;
+    while (match) {
+      index = match.index;
 
-  for (index = 0, length = objectKeyList.length; index < length; index += 1) {
-    pairBuffer = '';
+      // when we cross the max len, if the previous match would've
+      // been ok, use that one, and carry on.  If there was no previous
+      // match on this fold section, then just have a long line.
+      if (index - foldStart > max) {
+        if (prevMatch !== foldStart) {
+          foldEnd = prevMatch;
+        } else {
+          foldEnd = index;
+        }
 
-    if (!compact || 0 !== index) {
-      pairBuffer += generateNextLine(state, level);
+        if (result) {
+          result += '\n';
+        }
+        folded = line.slice(foldStart, foldEnd);
+        result += folded;
+        foldStart = foldEnd + 1;
+      }
+      prevMatch = index + 1;
+      match = foldRe.exec(line);
     }
 
-    objectKey = objectKeyList[index];
-    objectValue = object[objectKey];
+    if (result) {
+      result += '\n';
+    }
 
-    if (!writeNode(state, level + 1, objectKey, true, true)) {
-      continue; // Skip this pair because of invalid key.
+    // if we end up with one last word at the end, then the last bit might
+    // be slightly bigger than we wanted, because we exited out of the loop.
+    if (foldStart !== prevMatch && line.length - foldStart > max) {
+      result += line.slice(foldStart, prevMatch) + '\n' +
+          line.slice(prevMatch + 1);
+    } else {
+      result += line.slice(foldStart);
+    }
+
+    return result;
+  }
+
+// Returns true if character can be found in a simple scalar
+  function simpleChar(character) {
+    return CHAR_TAB                  !== character &&
+        CHAR_LINE_FEED            !== character &&
+        CHAR_CARRIAGE_RETURN      !== character &&
+        CHAR_COMMA                !== character &&
+        CHAR_LEFT_SQUARE_BRACKET  !== character &&
+        CHAR_RIGHT_SQUARE_BRACKET !== character &&
+        CHAR_LEFT_CURLY_BRACKET   !== character &&
+        CHAR_RIGHT_CURLY_BRACKET  !== character &&
+        CHAR_SHARP                !== character &&
+        CHAR_AMPERSAND            !== character &&
+        CHAR_ASTERISK             !== character &&
+        CHAR_EXCLAMATION          !== character &&
+        CHAR_VERTICAL_LINE        !== character &&
+        CHAR_GREATER_THAN         !== character &&
+        CHAR_SINGLE_QUOTE         !== character &&
+        CHAR_DOUBLE_QUOTE         !== character &&
+        CHAR_PERCENT              !== character &&
+        CHAR_COLON                !== character &&
+        !ESCAPE_SEQUENCES[character]            &&
+        !needsHexEscape(character);
+  }
+
+// Returns true if the character code needs to be escaped.
+  function needsHexEscape(character) {
+    return !((0x00020 <= character && character <= 0x00007E) ||
+    (0x00085 === character)                         ||
+    (0x000A0 <= character && character <= 0x00D7FF) ||
+    (0x0E000 <= character && character <= 0x00FFFD) ||
+    (0x10000 <= character && character <= 0x10FFFF));
+  }
+
+  function writeFlowSequence(state, level, object) {
+    var _result = '',
+        _tag    = state.tag,
+        index,
+        length;
+
+    for (index = 0, length = object.length; index < length; index += 1) {
+      // Write only valid elements.
+      if (writeNode(state, level, object[index], false, false)) {
+        if (0 !== index) {
+          _result += ', ';
+        }
+        _result += state.dump;
+      }
     }
 
-    explicitPair = (null !== state.tag && '?' !== state.tag) ||
-                   (state.dump && state.dump.length > 1024);
+    state.tag = _tag;
+    state.dump = '[' + _result + ']';
+  }
+
+  function writeBlockSequence(state, level, object, compact) {
+    var _result = '',
+        _tag    = state.tag,
+        index,
+        length;
 
-    if (explicitPair) {
-      if (state.dump && CHAR_LINE_FEED === state.dump.charCodeAt(0)) {
-        pairBuffer += '?';
-      } else {
-        pairBuffer += '? ';
+    for (index = 0, length = object.length; index < length; index += 1) {
+      // Write only valid elements.
+      if (writeNode(state, level + 1, object[index], true, true)) {
+        if (!compact || 0 !== index) {
+          _result += generateNextLine(state, level);
+        }
+        _result += '- ' + state.dump;
       }
     }
 
-    pairBuffer += state.dump;
+    state.tag = _tag;
+    state.dump = _result || '[]'; // Empty sequence if no valid values.
+  }
 
-    if (explicitPair) {
-      pairBuffer += generateNextLine(state, level);
-    }
+  function writeFlowMapping(state, level, object) {
+    var _result       = '',
+        _tag          = state.tag,
+        objectKeyList = Object.keys(object),
+        index,
+        length,
+        objectKey,
+        objectValue,
+        pairBuffer;
 
-    if (!writeNode(state, level + 1, objectValue, true, explicitPair)) {
-      continue; // Skip this pair because of invalid value.
-    }
+    for (index = 0, length = objectKeyList.length; index < length; index += 1) {
+      pairBuffer = '';
 
-    if (state.dump && CHAR_LINE_FEED === state.dump.charCodeAt(0)) {
-      pairBuffer += ':';
-    } else {
-      pairBuffer += ': ';
-    }
+      if (0 !== index) {
+        pairBuffer += ', ';
+      }
 
-    pairBuffer += state.dump;
+      objectKey = objectKeyList[index];
+      objectValue = object[objectKey];
 
-    // Both key and value are valid.
-    _result += pairBuffer;
-  }
+      if (!writeNode(state, level, objectKey, false, false)) {
+        continue; // Skip this pair because of invalid key;
+      }
+
+      if (state.dump.length > 1024) {
+        pairBuffer += '? ';
+      }
+
+      pairBuffer += state.dump + ': ';
+
+      if (!writeNode(state, level, objectValue, false, false)) {
+        continue; // Skip this pair because of invalid value.
+      }
 
-  state.tag = _tag;
-  state.dump = _result || '{}'; // Empty mapping if no valid pairs.
-}
+      pairBuffer += state.dump;
 
-function detectType(state, object, explicit) {
-  var _result, typeList, index, length, type, style;
+      // Both key and value are valid.
+      _result += pairBuffer;
+    }
 
-  typeList = explicit ? state.explicitTypes : state.implicitTypes;
+    state.tag = _tag;
+    state.dump = '{' + _result + '}';
+  }
+
+  function writeBlockMapping(state, level, object, compact) {
+    var _result       = '',
+        _tag          = state.tag,
+        objectKeyList = Object.keys(object),
+        index,
+        length,
+        objectKey,
+        objectValue,
+        explicitPair,
+        pairBuffer;
+
+    // Allow sorting keys so that the output file is deterministic
+    if (state.sortKeys === true) {
+      // Default sorting
+      objectKeyList.sort();
+    } else if (typeof state.sortKeys === 'function') {
+      // Custom sort function
+      objectKeyList.sort(state.sortKeys);
+    } else if (state.sortKeys) {
+      // Something is wrong
+      throw new YAMLException('sortKeys must be a boolean or a function');
+    }
+
+    for (index = 0, length = objectKeyList.length; index < length; index += 1) {
+      pairBuffer = '';
 
-  for (index = 0, length = typeList.length; index < length; index += 1) {
-    type = typeList[index];
+      if (!compact || 0 !== index) {
+        pairBuffer += generateNextLine(state, level);
+      }
 
-    if ((type.instanceOf  || type.predicate) &&
-        (!type.instanceOf || (('object' === typeof object) && (object instanceof type.instanceOf))) &&
-        (!type.predicate  || type.predicate(object))) {
+      objectKey = objectKeyList[index];
+      objectValue = object[objectKey];
 
-      state.tag = explicit ? type.tag : '?';
+      if (!writeNode(state, level + 1, objectKey, true, true, true)) {
+        continue; // Skip this pair because of invalid key.
+      }
 
-      if (type.represent) {
-        style = state.styleMap[type.tag] || type.defaultStyle;
+      explicitPair = (null !== state.tag && '?' !== state.tag) ||
+          (state.dump && state.dump.length > 1024);
 
-        if ('[object Function]' === _toString.call(type.represent)) {
-          _result = type.represent(object, style);
-        } else if (_hasOwnProperty.call(type.represent, style)) {
-          _result = type.represent[style](object, style);
+      if (explicitPair) {
+        if (state.dump && CHAR_LINE_FEED === state.dump.charCodeAt(0)) {
+          pairBuffer += '?';
         } else {
-          throw new YAMLException('!<' + type.tag + '> tag resolver accepts not "' + style + '" style');
+          pairBuffer += '? ';
         }
+      }
+
+      pairBuffer += state.dump;
 
-        state.dump = _result;
+      if (explicitPair) {
+        pairBuffer += generateNextLine(state, level);
       }
 
-      return true;
+      if (!writeNode(state, level + 1, objectValue, true, explicitPair)) {
+        continue; // Skip this pair because of invalid value.
+      }
+
+      if (state.dump && CHAR_LINE_FEED === state.dump.charCodeAt(0)) {
+        pairBuffer += ':';
+      } else {
+        pairBuffer += ': ';
+      }
+
+      pairBuffer += state.dump;
+
+      // Both key and value are valid.
+      _result += pairBuffer;
     }
+
+    state.tag = _tag;
+    state.dump = _result || '{}'; // Empty mapping if no valid pairs.
   }
 
-  return false;
-}
+  function detectType(state, object, explicit) {
+    var _result, typeList, index, length, type, style;
+
+    typeList = explicit ? state.explicitTypes : state.implicitTypes;
+
+    for (index = 0, length = typeList.length; index < length; index += 1) {
+      type = typeList[index];
+
+      if ((type.instanceOf  || type.predicate) &&
+          (!type.instanceOf || (('object' === typeof object) && (object instanceof type.instanceOf))) &&
+          (!type.predicate  || type.predicate(object))) {
+
+        state.tag = explicit ? type.tag : '?';
+
+        if (type.represent) {
+          style = state.styleMap[type.tag] || type.defaultStyle;
+
+          if ('[object Function]' === _toString.call(type.represent)) {
+            _result = type.represent(object, style);
+          } else if (_hasOwnProperty.call(type.represent, style)) {
+            _result = type.represent[style](object, style);
+          } else {
+            throw new YAMLException('!<' + type.tag + '> tag resolver accepts not "' + style + '" style');
+          }
+
+          state.dump = _result;
+        }
+
+        return true;
+      }
+    }
+
+    return false;
+  }
 
 // Serializes `object` and writes it to global `result`.
 // Returns true on success, or false on invalid object.
 //
-function writeNode(state, level, object, block, compact) {
-  state.tag = null;
-  state.dump = object;
-
-  if (!detectType(state, object, false)) {
-    detectType(state, object, true);
-  }
+  function writeNode(state, level, object, block, compact, iskey) {
+    state.tag = null;
+    state.dump = object;
 
-  var type = _toString.call(state.dump);
+    if (!detectType(state, object, false)) {
+      detectType(state, object, true);
+    }
 
-  if (block) {
-    block = (0 > state.flowLevel || state.flowLevel > level);
-  }
+    var type = _toString.call(state.dump);
 
-  if ((null !== state.tag && '?' !== state.tag) || (2 !== state.indent && level > 0)) {
-    compact = false;
-  }
+    if (block) {
+      block = (0 > state.flowLevel || state.flowLevel > level);
+    }
 
-  var objectOrArray = '[object Object]' === type || '[object Array]' === type,
-      duplicateIndex,
-      duplicate;
+    var objectOrArray = '[object Object]' === type || '[object Array]' === type,
+        duplicateIndex,
+        duplicate;
 
-  if (objectOrArray) {
-    duplicateIndex = state.duplicates.indexOf(object);
-    duplicate = duplicateIndex !== -1;
-  }
+    if (objectOrArray) {
+      duplicateIndex = state.duplicates.indexOf(object);
+      duplicate = duplicateIndex !== -1;
+    }
 
-  if (duplicate && state.usedDuplicates[duplicateIndex]) {
-    state.dump = '*ref_' + duplicateIndex;
-  } else {
-    if (objectOrArray && duplicate && !state.usedDuplicates[duplicateIndex]) {
-      state.usedDuplicates[duplicateIndex] = true;
+    if ((null !== state.tag && '?' !== state.tag) || duplicate || (2 !== state.indent && level > 0)) {
+      compact = false;
     }
-    if ('[object Object]' === type) {
-      if (block && (0 !== Object.keys(state.dump).length)) {
-        writeBlockMapping(state, level, state.dump, compact);
-        if (duplicate) {
-          state.dump = '&ref_' + duplicateIndex + (0 === level ? '\n' : '') + state.dump;
+
+    if (duplicate && state.usedDuplicates[duplicateIndex]) {
+      state.dump = '*ref_' + duplicateIndex;
+    } else {
+      if (objectOrArray && duplicate && !state.usedDuplicates[duplicateIndex]) {
+        state.usedDuplicates[duplicateIndex] = true;
+      }
+      if ('[object Object]' === type) {
+        if (block && (0 !== Object.keys(state.dump).length)) {
+          writeBlockMapping(state, level, state.dump, compact);
+          if (duplicate) {
+            state.dump = '&ref_' + duplicateIndex + state.dump;
+          }
+        } else {
+          writeFlowMapping(state, level, state.dump);
+          if (duplicate) {
+            state.dump = '&ref_' + duplicateIndex + ' ' + state.dump;
+          }
         }
-      } else {
-        writeFlowMapping(state, level, state.dump);
-        if (duplicate) {
-          state.dump = '&ref_' + duplicateIndex + ' ' + state.dump;
+      } else if ('[object Array]' === type) {
+        if (block && (0 !== state.dump.length)) {
+          writeBlockSequence(state, level, state.dump, compact);
+          if (duplicate) {
+            state.dump = '&ref_' + duplicateIndex + state.dump;
+          }
+        } else {
+          writeFlowSequence(state, level, state.dump);
+          if (duplicate) {
+            state.dump = '&ref_' + duplicateIndex + ' ' + state.dump;
+          }
         }
-      }
-    } else if ('[object Array]' === type) {
-      if (block && (0 !== state.dump.length)) {
-        writeBlockSequence(state, level, state.dump, compact);
-        if (duplicate) {
-          state.dump = '&ref_' + duplicateIndex + (0 === level ? '\n' : '') + state.dump;
+      } else if ('[object String]' === type) {
+        if ('?' !== state.tag) {
+          writeScalar(state, state.dump, level, iskey);
         }
       } else {
-        writeFlowSequence(state, level, state.dump);
-        if (duplicate) {
-          state.dump = '&ref_' + duplicateIndex + ' ' + state.dump;
+        if (state.skipInvalid) {
+          return false;
         }
+        throw new YAMLException('unacceptable kind of an object to dump ' + type);
       }
-    } else if ('[object String]' === type) {
-      if ('?' !== state.tag) {
-        writeScalar(state, state.dump);
+
+      if (null !== state.tag && '?' !== state.tag) {
+        state.dump = '!<' + state.tag + '> ' + state.dump;
       }
-    } else if (state.skipInvalid) {
-      return false;
-    } else {
-      throw new YAMLException('unacceptable kind of an object to dump ' + type);
     }
 
-    if (null !== state.tag && '?' !== state.tag) {
-      state.dump = '!<' + state.tag + '> ' + state.dump;
-    }
+    return true;
   }
 
-  return true;
-}
+  function getDuplicateReferences(object, state) {
+    var objects = [],
+        duplicatesIndexes = [],
+        index,
+        length;
 
-function getDuplicateReferences(object, state) {
-  var objects = [],
-      duplicatesIndexes = [],
-      index,
-      length;
+    inspectNode(object, objects, duplicatesIndexes);
 
-  inspectNode(object, objects, duplicatesIndexes);
-
-  for (index = 0, length = duplicatesIndexes.length; index < length; index += 1) {
-    state.duplicates.push(objects[duplicatesIndexes[index]]);
+    for (index = 0, length = duplicatesIndexes.length; index < length; index += 1) {
+      state.duplicates.push(objects[duplicatesIndexes[index]]);
+    }
+    state.usedDuplicates = new Array(length);
   }
-  state.usedDuplicates = new Array(length);
-}
 
-function inspectNode(object, objects, duplicatesIndexes) {
-  var type = _toString.call(object),
-      objectKeyList,
-      index,
-      length;
+  function inspectNode(object, objects, duplicatesIndexes) {
+    var objectKeyList,
+        index,
+        length;
 
-  if (null !== object && 'object' === typeof object) {
-    index = objects.indexOf(object);
-    if (-1 !== index) {
-      if (-1 === duplicatesIndexes.indexOf(index)) {
-        duplicatesIndexes.push(index);
-      }
-    } else {
-      objects.push(object);
-    
-      if(Array.isArray(object)) {
-        for (index = 0, length = object.length; index < length; index += 1) {
-          inspectNode(object[index], objects, duplicatesIndexes);
+    if (null !== object && 'object' === typeof object) {
+      index = objects.indexOf(object);
+      if (-1 !== index) {
+        if (-1 === duplicatesIndexes.indexOf(index)) {
+          duplicatesIndexes.push(index);
         }
       } else {
-        objectKeyList = Object.keys(object);
+        objects.push(object);
 
-        for (index = 0, length = objectKeyList.length; index < length; index += 1) {
-          inspectNode(object[objectKeyList[index]], objects, duplicatesIndexes);
+        if (Array.isArray(object)) {
+          for (index = 0, length = object.length; index < length; index += 1) {
+            inspectNode(object[index], objects, duplicatesIndexes);
+          }
+        } else {
+          objectKeyList = Object.keys(object);
+
+          for (index = 0, length = objectKeyList.length; index < length; index += 1) {
+            inspectNode(object[objectKeyList[index]], objects, duplicatesIndexes);
+          }
         }
       }
     }
   }
-}
 
-function dump(input, options) {
-  options = options || {};
+  function dump(input, options) {
+    options = options || {};
 
-  var state = new State(options);
+    var state = new State(options);
 
-  getDuplicateReferences(input, state);
+    if (!state.noRefs) {
+      getDuplicateReferences(input, state);
+    }
 
-  if (writeNode(state, 0, input, true, true)) {
-    return state.dump + '\n';
-  } else {
+    if (writeNode(state, 0, input, true, true)) {
+      return state.dump + '\n';
+    }
     return '';
   }
-}
-
-
-function safeDump(input, options) {
-  return dump(input, common.extend({ schema: DEFAULT_SAFE_SCHEMA }, options));
-}
 
+  function safeDump(input, options) {
+    return dump(input, common.extend({ schema: DEFAULT_SAFE_SCHEMA }, options));
+  }
 
-module.exports.dump     = dump;
-module.exports.safeDump = safeDump;
+  module.exports.dump     = dump;
+  module.exports.safeDump = safeDump;
 
 },{"./common":2,"./exception":4,"./schema/default_full":9,"./schema/default_safe":10}],4:[function(require,module,exports){
-'use strict';
+// YAML error class. http://stackoverflow.com/questions/8458984
+//
+  'use strict';
 
+  function YAMLException(reason, mark) {
+    // Super constructor
+    Error.call(this);
 
-function YAMLException(reason, mark) {
-  this.name    = 'YAMLException';
-  this.reason  = reason;
-  this.mark    = mark;
-  this.message = this.toString(false);
-}
+    // Include stack trace in error object
+    if (Error.captureStackTrace) {
+      // Chrome and NodeJS
+      Error.captureStackTrace(this, this.constructor);
+    } else {
+      // FF, IE 10+ and Safari 6+. Fallback for others
+      this.stack = (new Error()).stack || '';
+    }
 
+    this.name = 'YAMLException';
+    this.reason = reason;
+    this.mark = mark;
+    this.message = (this.reason || '(unknown reason)') + (this.mark ? ' ' + this.mark.toString() : '');
+  }
 
-YAMLException.prototype.toString = function toString(compact) {
-  var result;
 
-  result = 'JS-YAML: ' + (this.reason || '(unknown reason)');
+// Inherit from Error
+  YAMLException.prototype = Object.create(Error.prototype);
+  YAMLException.prototype.constructor = YAMLException;
 
-  if (!compact && this.mark) {
-    result += ' ' + this.mark.toString();
-  }
 
-  return result;
-};
+  YAMLException.prototype.toString = function toString(compact) {
+    var result = this.name + ': ';
 
+    result += this.reason || '(unknown reason)';
 
-module.exports = YAMLException;
+    if (!compact && this.mark) {
+      result += ' ' + this.mark.toString();
+    }
 
-},{}],5:[function(require,module,exports){
-'use strict';
+    return result;
+  };
 
 
-var common              = require('./common');
-var YAMLException       = require('./exception');
-var Mark                = require('./mark');
-var DEFAULT_SAFE_SCHEMA = require('./schema/default_safe');
-var DEFAULT_FULL_SCHEMA = require('./schema/default_full');
+  module.exports = YAMLException;
 
+},{}],5:[function(require,module,exports){
+  'use strict';
 
-var _hasOwnProperty = Object.prototype.hasOwnProperty;
+  /*eslint-disable max-len,no-use-before-define*/
 
+  var common              = require('./common');
+  var YAMLException       = require('./exception');
+  var Mark                = require('./mark');
+  var DEFAULT_SAFE_SCHEMA = require('./schema/default_safe');
+  var DEFAULT_FULL_SCHEMA = require('./schema/default_full');
 
-var CONTEXT_FLOW_IN   = 1;
-var CONTEXT_FLOW_OUT  = 2;
-var CONTEXT_BLOCK_IN  = 3;
-var CONTEXT_BLOCK_OUT = 4;
 
+  var _hasOwnProperty = Object.prototype.hasOwnProperty;
 
-var CHOMPING_CLIP  = 1;
-var CHOMPING_STRIP = 2;
-var CHOMPING_KEEP  = 3;
 
+  var CONTEXT_FLOW_IN   = 1;
+  var CONTEXT_FLOW_OUT  = 2;
+  var CONTEXT_BLOCK_IN  = 3;
+  var CONTEXT_BLOCK_OUT = 4;
 
-var PATTERN_NON_PRINTABLE         = /[\x00-\x08\x0B\x0C\x0E-\x1F\x7F-\x84\x86-\x9F\uD800-\uDFFF\uFFFE\uFFFF]/;
-var PATTERN_NON_ASCII_LINE_BREAKS = /[\x85\u2028\u2029]/;
-var PATTERN_FLOW_INDICATORS       = /[,\[\]\{\}]/;
-var PATTERN_TAG_HANDLE            = /^(?:!|!!|![a-z\-]+!)$/i;
-var PATTERN_TAG_URI               = /^(?:!|[^,\[\]\{\}])(?:%[0-9a-f]{2}|[0-9a-z\-#;\/\?:@&=\+\$,_\.!~\*'\(\)\[\]])*$/i;
 
+  var CHOMPING_CLIP  = 1;
+  var CHOMPING_STRIP = 2;
+  var CHOMPING_KEEP  = 3;
 
-function is_EOL(c) {
-  return (c === 0x0A/* LF */) || (c === 0x0D/* CR */);
-}
 
-function is_WHITE_SPACE(c) {
-  return (c === 0x09/* Tab */) || (c === 0x20/* Space */);
-}
+  var PATTERN_NON_PRINTABLE         = /[\x00-\x08\x0B\x0C\x0E-\x1F\x7F-\x84\x86-\x9F\uFFFE\uFFFF]|[\uD800-\uDBFF](?![\uDC00-\uDFFF])|(?:[^\uD800-\uDBFF]|^)[\uDC00-\uDFFF]/;
+  var PATTERN_NON_ASCII_LINE_BREAKS = /[\x85\u2028\u2029]/;
+  var PATTERN_FLOW_INDICATORS       = /[,\[\]\{\}]/;
+  var PATTERN_TAG_HANDLE            = /^(?:!|!!|![a-z\-]+!)$/i;
+  var PATTERN_TAG_URI               = /^(?:!|[^,\[\]\{\}])(?:%[0-9a-f]{2}|[0-9a-z\-#;\/\?:@&=\+\$,_\.!~\*'\(\)\[\]])*$/i;
 
-function is_WS_OR_EOL(c) {
-  return (c === 0x09/* Tab */) ||
-         (c === 0x20/* Space */) ||
-         (c === 0x0A/* LF */) ||
-         (c === 0x0D/* CR */);
-}
 
-function is_FLOW_INDICATOR(c) {
-  return 0x2C/* , */ === c ||
-         0x5B/* [ */ === c ||
-         0x5D/* ] */ === c ||
-         0x7B/* { */ === c ||
-         0x7D/* } */ === c;
-}
+  function is_EOL(c) {
+    return (c === 0x0A/* LF */) || (c === 0x0D/* CR */);
+  }
 
-function fromHexCode(c) {
-  var lc;
+  function is_WHITE_SPACE(c) {
+    return (c === 0x09/* Tab */) || (c === 0x20/* Space */);
+  }
 
-  if ((0x30/* 0 */ <= c) && (c <= 0x39/* 9 */)) {
-    return c - 0x30;
+  function is_WS_OR_EOL(c) {
+    return (c === 0x09/* Tab */) ||
+        (c === 0x20/* Space */) ||
+        (c === 0x0A/* LF */) ||
+        (c === 0x0D/* CR */);
   }
 
-  lc = c | 0x20;
-  if ((0x61/* a */ <= lc) && (lc <= 0x66/* f */)) {
-    return lc - 0x61 + 10;
+  function is_FLOW_INDICATOR(c) {
+    return 0x2C/* , */ === c ||
+        0x5B/* [ */ === c ||
+        0x5D/* ] */ === c ||
+        0x7B/* { */ === c ||
+        0x7D/* } */ === c;
   }
 
-  return -1;
-}
+  function fromHexCode(c) {
+    var lc;
+
+    if ((0x30/* 0 */ <= c) && (c <= 0x39/* 9 */)) {
+      return c - 0x30;
+    }
+
+    /*eslint-disable no-bitwise*/
+    lc = c | 0x20;
+
+    if ((0x61/* a */ <= lc) && (lc <= 0x66/* f */)) {
+      return lc - 0x61 + 10;
+    }
 
-function escapedHexLen(c) {
-  if (c === 0x78/* x */) { return 2; }
-  if (c === 0x75/* u */) { return 4; }
-  if (c === 0x55/* U */) { return 8; }
-  return 0;
-}
+    return -1;
+  }
 
-function fromDecimalCode(c) {
-  if ((0x30/* 0 */ <= c) && (c <= 0x39/* 9 */)) {
-    return c - 0x30;
+  function escapedHexLen(c) {
+    if (c === 0x78/* x */) { return 2; }
+    if (c === 0x75/* u */) { return 4; }
+    if (c === 0x55/* U */) { return 8; }
+    return 0;
   }
 
-  return -1;
-}
+  function fromDecimalCode(c) {
+    if ((0x30/* 0 */ <= c) && (c <= 0x39/* 9 */)) {
+      return c - 0x30;
+    }
+
+    return -1;
+  }
 
-function simpleEscapeSequence(c) {
- return (c === 0x30/* 0 */) ? '\x00' :
+  function simpleEscapeSequence(c) {
+    return (c === 0x30/* 0 */) ? '\x00' :
         (c === 0x61/* a */) ? '\x07' :
-        (c === 0x62/* b */) ? '\x08' :
-        (c === 0x74/* t */) ? '\x09' :
-        (c === 0x09/* Tab */) ? '\x09' :
-        (c === 0x6E/* n */) ? '\x0A' :
-        (c === 0x76/* v */) ? '\x0B' :
-        (c === 0x66/* f */) ? '\x0C' :
-        (c === 0x72/* r */) ? '\x0D' :
-        (c === 0x65/* e */) ? '\x1B' :
-        (c === 0x20/* Space */) ? ' ' :
-        (c === 0x22/* " */) ? '\x22' :
-        (c === 0x2F/* / */) ? '/' :
-        (c === 0x5C/* \ */) ? '\x5C' :
-        (c === 0x4E/* N */) ? '\x85' :
-        (c === 0x5F/* _ */) ? '\xA0' :
-        (c === 0x4C/* L */) ? '\u2028' :
-        (c === 0x50/* P */) ? '\u2029' : '';
-}
-
-function charFromCodepoint(c) {
-  if (c <= 0xFFFF) {
-    return String.fromCharCode(c);
-  } else {
+            (c === 0x62/* b */) ? '\x08' :
+                (c === 0x74/* t */) ? '\x09' :
+                    (c === 0x09/* Tab */) ? '\x09' :
+                        (c === 0x6E/* n */) ? '\x0A' :
+                            (c === 0x76/* v */) ? '\x0B' :
+                                (c === 0x66/* f */) ? '\x0C' :
+                                    (c === 0x72/* r */) ? '\x0D' :
+                                        (c === 0x65/* e */) ? '\x1B' :
+                                            (c === 0x20/* Space */) ? ' ' :
+                                                (c === 0x22/* " */) ? '\x22' :
+                                                    (c === 0x2F/* / */) ? '/' :
+                                                        (c === 0x5C/* \ */) ? '\x5C' :
+                                                            (c === 0x4E/* N */) ? '\x85' :
+                                                                (c === 0x5F/* _ */) ? '\xA0' :
+                                                                    (c === 0x4C/* L */) ? '\u2028' :
+                                                                        (c === 0x50/* P */) ? '\u2029' : '';
+  }
+
+  function charFromCodepoint(c) {
+    if (c <= 0xFFFF) {
+      return String.fromCharCode(c);
+    }
     // Encode UTF-16 surrogate pair
     // https://en.wikipedia.org/wiki/UTF-16#Code_points_U.2B010000_to_U.2B10FFFF
     return String.fromCharCode(((c - 0x010000) >> 10) + 0xD800,
-                               ((c - 0x010000) & 0x03FF) + 0xDC00);
+        ((c - 0x010000) & 0x03FF) + 0xDC00);
   }
-}
-
-var simpleEscapeCheck = new Array(256); // integer, for fast access
-var simpleEscapeMap = new Array(256);
-for (var i = 0; i < 256; i++) {
-  simpleEscapeCheck[i] = simpleEscapeSequence(i) ? 1 : 0;
-  simpleEscapeMap[i] = simpleEscapeSequence(i);
-}
 
+  var simpleEscapeCheck = new Array(256); // integer, for fast access
+  var simpleEscapeMap = new Array(256);
+  for (var i = 0; i < 256; i++) {
+    simpleEscapeCheck[i] = simpleEscapeSequence(i) ? 1 : 0;
+    simpleEscapeMap[i] = simpleEscapeSequence(i);
+  }
 
-function State(input, options) {
-  this.input = input;
 
-  this.filename  = options['filename']  || null;
-  this.schema    = options['schema']    || DEFAULT_FULL_SCHEMA;
-  this.onWarning = options['onWarning'] || null;
-  this.legacy    = options['legacy']    || false;
+  function State(input, options) {
+    this.input = input;
 
-  this.implicitTypes = this.schema.compiledImplicit;
-  this.typeMap       = this.schema.compiledTypeMap;
+    this.filename  = options['filename']  || null;
+    this.schema    = options['schema']    || DEFAULT_FULL_SCHEMA;
+    this.onWarning = options['onWarning'] || null;
+    this.legacy    = options['legacy']    || false;
+    this.json      = options['json']      || false;
 
-  this.length     = input.length;
-  this.position   = 0;
-  this.line       = 0;
-  this.lineStart  = 0;
-  this.lineIndent = 0;
+    this.implicitTypes = this.schema.compiledImplicit;
+    this.typeMap       = this.schema.compiledTypeMap;
 
-  this.documents = [];
+    this.length     = input.length;
+    this.position   = 0;
+    this.line       = 0;
+    this.lineStart  = 0;
+    this.lineIndent = 0;
 
-  /*
-  this.version;
-  this.checkLineBreaks;
-  this.tagMap;
-  this.anchorMap;
-  this.tag;
-  this.anchor;
-  this.kind;
-  this.result;*/
+    this.documents = [];
 
-}
+    /*
+     this.version;
+     this.checkLineBreaks;
+     this.tagMap;
+     this.anchorMap;
+     this.tag;
+     this.anchor;
+     this.kind;
+     this.result;*/
 
+  }
 
-function generateError(state, message) {
-  return new YAMLException(
-    message,
-    new Mark(state.filename, state.input, state.position, state.line, (state.position - state.lineStart)));
-}
 
-function throwError(state, message) {
-  throw generateError(state, message);
-}
+  function generateError(state, message) {
+    return new YAMLException(
+        message,
+        new Mark(state.filename, state.input, state.position, state.line, (state.position - state.lineStart)));
+  }
 
-function throwWarning(state, message) {
-  var error = generateError(state, message);
+  function throwError(state, message) {
+    throw generateError(state, message);
+  }
 
-  if (state.onWarning) {
-    state.onWarning.call(null, error);
-  } else {
-    throw error;
+  function throwWarning(state, message) {
+    if (state.onWarning) {
+      state.onWarning.call(null, generateError(state, message));
+    }
   }
-}
 
 
-var directiveHandlers = {
+  var directiveHandlers = {
 
-  'YAML': function handleYamlDirective(state, name, args) {
+    YAML: function handleYamlDirective(state, name, args) {
 
       var match, major, minor;
 
@@ -899,7 +1215,7 @@ var directiveHandlers = {
       }
     },
 
-  'TAG': function handleTagDirective(state, name, args) {
+    TAG: function handleTagDirective(state, name, args) {
 
       var handle, prefix;
 
@@ -924,793 +1240,809 @@ var directiveHandlers = {
 
       state.tagMap[handle] = prefix;
     }
-};
+  };
 
 
-function captureSegment(state, start, end, checkJson) {
-  var _position, _length, _character, _result;
+  function captureSegment(state, start, end, checkJson) {
+    var _position, _length, _character, _result;
 
-  if (start < end) {
-    _result = state.input.slice(start, end);
+    if (start < end) {
+      _result = state.input.slice(start, end);
 
-    if (checkJson) {
-      for (_position = 0, _length = _result.length;
-           _position < _length;
-           _position += 1) {
-        _character = _result.charCodeAt(_position);
-        if (!(0x09 === _character ||
+      if (checkJson) {
+        for (_position = 0, _length = _result.length;
+             _position < _length;
+             _position += 1) {
+          _character = _result.charCodeAt(_position);
+          if (!(0x09 === _character ||
               0x20 <= _character && _character <= 0x10FFFF)) {
-          throwError(state, 'expected valid JSON character');
+            throwError(state, 'expected valid JSON character');
+          }
         }
+      } else if (PATTERN_NON_PRINTABLE.test(_result)) {
+        throwError(state, 'the stream contains non-printable characters');
       }
-    }
 
-    state.result += _result;
+      state.result += _result;
+    }
   }
-}
 
-function mergeMappings(state, destination, source) {
-  var sourceKeys, key, index, quantity;
+  function mergeMappings(state, destination, source, overridableKeys) {
+    var sourceKeys, key, index, quantity;
 
-  if (!common.isObject(source)) {
-    throwError(state, 'cannot merge mappings; the provided source object is unacceptable');
-  }
+    if (!common.isObject(source)) {
+      throwError(state, 'cannot merge mappings; the provided source object is unacceptable');
+    }
 
-  sourceKeys = Object.keys(source);
+    sourceKeys = Object.keys(source);
 
-  for (index = 0, quantity = sourceKeys.length; index < quantity; index += 1) {
-    key = sourceKeys[index];
+    for (index = 0, quantity = sourceKeys.length; index < quantity; index += 1) {
+      key = sourceKeys[index];
 
-    if (!_hasOwnProperty.call(destination, key)) {
-      destination[key] = source[key];
+      if (!_hasOwnProperty.call(destination, key)) {
+        destination[key] = source[key];
+        overridableKeys[key] = true;
+      }
     }
   }
-}
 
-function storeMappingPair(state, _result, keyTag, keyNode, valueNode) {
-  var index, quantity;
+  function storeMappingPair(state, _result, overridableKeys, keyTag, keyNode, valueNode) {
+    var index, quantity;
 
-  keyNode = String(keyNode);
+    keyNode = String(keyNode);
 
-  if (null === _result) {
-    _result = {};
-  }
+    if (null === _result) {
+      _result = {};
+    }
 
-  if ('tag:yaml.org,2002:merge' === keyTag) {
-    if (Array.isArray(valueNode)) {
-      for (index = 0, quantity = valueNode.length; index < quantity; index += 1) {
-        mergeMappings(state, _result, valueNode[index]);
+    if ('tag:yaml.org,2002:merge' === keyTag) {
+      if (Array.isArray(valueNode)) {
+        for (index = 0, quantity = valueNode.length; index < quantity; index += 1) {
+          mergeMappings(state, _result, valueNode[index], overridableKeys);
+        }
+      } else {
+        mergeMappings(state, _result, valueNode, overridableKeys);
       }
     } else {
-      mergeMappings(state, _result, valueNode);
+      if (!state.json &&
+          !_hasOwnProperty.call(overridableKeys, keyNode) &&
+          _hasOwnProperty.call(_result, keyNode)) {
+        throwError(state, 'duplicated mapping key');
+      }
+      _result[keyNode] = valueNode;
+      delete overridableKeys[keyNode];
     }
-  } else {
-    _result[keyNode] = valueNode;
-  }
 
-  return _result;
-}
+    return _result;
+  }
 
-function readLineBreak(state) {
-  var ch;
+  function readLineBreak(state) {
+    var ch;
 
-  ch = state.input.charCodeAt(state.position);
+    ch = state.input.charCodeAt(state.position);
 
-  if (0x0A/* LF */ === ch) {
-    state.position++;
-  } else if (0x0D/* CR */ === ch) {
-    state.position++;
-    if (0x0A/* LF */ === state.input.charCodeAt(state.position)) {
+    if (0x0A/* LF */ === ch) {
       state.position++;
+    } else if (0x0D/* CR */ === ch) {
+      state.position++;
+      if (0x0A/* LF */ === state.input.charCodeAt(state.position)) {
+        state.position++;
+      }
+    } else {
+      throwError(state, 'a line break is expected');
     }
-  } else {
-    throwError(state, 'a line break is expected');
-  }
-
-  state.line += 1;
-  state.lineStart = state.position;
-}
 
-function skipSeparationSpace(state, allowComments, checkIndent) {
-  var lineBreaks = 0,
-      ch = state.input.charCodeAt(state.position);
+    state.line += 1;
+    state.lineStart = state.position;
+  }
 
-  while (0 !== ch) {
-    while (is_WHITE_SPACE(ch)) {
-      ch = state.input.charCodeAt(++state.position);
-    }
+  function skipSeparationSpace(state, allowComments, checkIndent) {
+    var lineBreaks = 0,
+        ch = state.input.charCodeAt(state.position);
 
-    if (allowComments && 0x23/* # */ === ch) {
-      do {
+    while (0 !== ch) {
+      while (is_WHITE_SPACE(ch)) {
         ch = state.input.charCodeAt(++state.position);
-      } while (ch !== 0x0A/* LF */ && ch !== 0x0D/* CR */ && 0 !== ch);
-    }
+      }
 
-    if (is_EOL(ch)) {
-      readLineBreak(state);
+      if (allowComments && 0x23/* # */ === ch) {
+        do {
+          ch = state.input.charCodeAt(++state.position);
+        } while (ch !== 0x0A/* LF */ && ch !== 0x0D/* CR */ && 0 !== ch);
+      }
 
-      ch = state.input.charCodeAt(state.position);
-      lineBreaks++;
-      state.lineIndent = 0;
+      if (is_EOL(ch)) {
+        readLineBreak(state);
 
-      while (0x20/* Space */ === ch) {
-        state.lineIndent++;
-        ch = state.input.charCodeAt(++state.position);
+        ch = state.input.charCodeAt(state.position);
+        lineBreaks++;
+        state.lineIndent = 0;
+
+        while (0x20/* Space */ === ch) {
+          state.lineIndent++;
+          ch = state.input.charCodeAt(++state.position);
+        }
+      } else {
+        break;
       }
-    } else {
-      break;
     }
-  }
 
-  if (-1 !== checkIndent && 0 !== lineBreaks && state.lineIndent < checkIndent) {
-    throwWarning(state, 'deficient indentation');
-  }
+    if (-1 !== checkIndent && 0 !== lineBreaks && state.lineIndent < checkIndent) {
+      throwWarning(state, 'deficient indentation');
+    }
 
-  return lineBreaks;
-}
+    return lineBreaks;
+  }
 
-function testDocumentSeparator(state) {
-  var _position = state.position,
-      ch;
+  function testDocumentSeparator(state) {
+    var _position = state.position,
+        ch;
 
-  ch = state.input.charCodeAt(_position);
+    ch = state.input.charCodeAt(_position);
 
-  // Condition state.position === state.lineStart is tested
-  // in parent on each call, for efficiency. No needs to test here again.
-  if ((0x2D/* - */ === ch || 0x2E/* . */ === ch) &&
-      state.input.charCodeAt(_position + 1) === ch &&
-      state.input.charCodeAt(_position+ 2) === ch) {
+    // Condition state.position === state.lineStart is tested
+    // in parent on each call, for efficiency. No needs to test here again.
+    if ((0x2D/* - */ === ch || 0x2E/* . */ === ch) &&
+        state.input.charCodeAt(_position + 1) === ch &&
+        state.input.charCodeAt(_position + 2) === ch) {
 
-    _position += 3;
+      _position += 3;
 
-    ch = state.input.charCodeAt(_position);
+      ch = state.input.charCodeAt(_position);
 
-    if (ch === 0 || is_WS_OR_EOL(ch)) {
-      return true;
+      if (ch === 0 || is_WS_OR_EOL(ch)) {
+        return true;
+      }
     }
-  }
 
-  return false;
-}
-
-function writeFoldedLines(state, count) {
-  if (1 === count) {
-    state.result += ' ';
-  } else if (count > 1) {
-    state.result += common.repeat('\n', count - 1);
-  }
-}
-
-
-function readPlainScalar(state, nodeIndent, withinFlowCollection) {
-  var preceding,
-      following,
-      captureStart,
-      captureEnd,
-      hasPendingContent,
-      _line,
-      _lineStart,
-      _lineIndent,
-      _kind = state.kind,
-      _result = state.result,
-      ch;
-
-  ch = state.input.charCodeAt(state.position);
-
-  if (is_WS_OR_EOL(ch)             ||
-      is_FLOW_INDICATOR(ch)        ||
-      0x23/* # */           === ch ||
-      0x26/* & */           === ch ||
-      0x2A/* * */           === ch ||
-      0x21/* ! */           === ch ||
-      0x7C/* | */           === ch ||
-      0x3E/* > */           === ch ||
-      0x27/* ' */           === ch ||
-      0x22/* " */           === ch ||
-      0x25/* % */           === ch ||
-      0x40/* @ */           === ch ||
-      0x60/* ` */           === ch) {
     return false;
   }
 
-  if (0x3F/* ? */ === ch || 0x2D/* - */ === ch) {
-    following = state.input.charCodeAt(state.position + 1);
-
-    if (is_WS_OR_EOL(following) ||
-        withinFlowCollection && is_FLOW_INDICATOR(following)) {
-      return false;
+  function writeFoldedLines(state, count) {
+    if (1 === count) {
+      state.result += ' ';
+    } else if (count > 1) {
+      state.result += common.repeat('\n', count - 1);
     }
   }
 
-  state.kind = 'scalar';
-  state.result = '';
-  captureStart = captureEnd = state.position;
-  hasPendingContent = false;
 
-  while (0 !== ch) {
-    if (0x3A/* : */ === ch) {
-      following = state.input.charCodeAt(state.position+1);
+  function readPlainScalar(state, nodeIndent, withinFlowCollection) {
+    var preceding,
+        following,
+        captureStart,
+        captureEnd,
+        hasPendingContent,
+        _line,
+        _lineStart,
+        _lineIndent,
+        _kind = state.kind,
+        _result = state.result,
+        ch;
+
+    ch = state.input.charCodeAt(state.position);
+
+    if (is_WS_OR_EOL(ch)             ||
+        is_FLOW_INDICATOR(ch)        ||
+        0x23/* # */           === ch ||
+        0x26/* & */           === ch ||
+        0x2A/* * */           === ch ||
+        0x21/* ! */           === ch ||
+        0x7C/* | */           === ch ||
+        0x3E/* > */           === ch ||
+        0x27/* ' */           === ch ||
+        0x22/* " */           === ch ||
+        0x25/* % */           === ch ||
+        0x40/* @ */           === ch ||
+        0x60/* ` */           === ch) {
+      return false;
+    }
+
+    if (0x3F/* ? */ === ch || 0x2D/* - */ === ch) {
+      following = state.input.charCodeAt(state.position + 1);
 
       if (is_WS_OR_EOL(following) ||
           withinFlowCollection && is_FLOW_INDICATOR(following)) {
-        break;
+        return false;
       }
+    }
 
-    } else if (0x23/* # */ === ch) {
-      preceding = state.input.charCodeAt(state.position - 1);
+    state.kind = 'scalar';
+    state.result = '';
+    captureStart = captureEnd = state.position;
+    hasPendingContent = false;
 
-      if (is_WS_OR_EOL(preceding)) {
-        break;
-      }
+    while (0 !== ch) {
+      if (0x3A/* : */ === ch) {
+        following = state.input.charCodeAt(state.position + 1);
 
-    } else if ((state.position === state.lineStart && testDocumentSeparator(state)) ||
-               withinFlowCollection && is_FLOW_INDICATOR(ch)) {
-      break;
+        if (is_WS_OR_EOL(following) ||
+            withinFlowCollection && is_FLOW_INDICATOR(following)) {
+          break;
+        }
 
-    } else if (is_EOL(ch)) {
-      _line = state.line;
-      _lineStart = state.lineStart;
-      _lineIndent = state.lineIndent;
-      skipSeparationSpace(state, false, -1);
+      } else if (0x23/* # */ === ch) {
+        preceding = state.input.charCodeAt(state.position - 1);
 
-      if (state.lineIndent >= nodeIndent) {
-        hasPendingContent = true;
-        ch = state.input.charCodeAt(state.position);
-        continue;
-      } else {
-        state.position = captureEnd;
-        state.line = _line;
-        state.lineStart = _lineStart;
-        state.lineIndent = _lineIndent;
+        if (is_WS_OR_EOL(preceding)) {
+          break;
+        }
+
+      } else if ((state.position === state.lineStart && testDocumentSeparator(state)) ||
+          withinFlowCollection && is_FLOW_INDICATOR(ch)) {
         break;
+
+      } else if (is_EOL(ch)) {
+        _line = state.line;
+        _lineStart = state.lineStart;
+        _lineIndent = state.lineIndent;
+        skipSeparationSpace(state, false, -1);
+
+        if (state.lineIndent >= nodeIndent) {
+          hasPendingContent = true;
+          ch = state.input.charCodeAt(state.position);
+          continue;
+        } else {
+          state.position = captureEnd;
+          state.line = _line;
+          state.lineStart = _lineStart;
+          state.lineIndent = _lineIndent;
+          break;
+        }
       }
-    }
 
-    if (hasPendingContent) {
-      captureSegment(state, captureStart, captureEnd, false);
-      writeFoldedLines(state, state.line - _line);
-      captureStart = captureEnd = state.position;
-      hasPendingContent = false;
-    }
+      if (hasPendingContent) {
+        captureSegment(state, captureStart, captureEnd, false);
+        writeFoldedLines(state, state.line - _line);
+        captureStart = captureEnd = state.position;
+        hasPendingContent = false;
+      }
+
+      if (!is_WHITE_SPACE(ch)) {
+        captureEnd = state.position + 1;
+      }
 
-    if (!is_WHITE_SPACE(ch)) {
-      captureEnd = state.position + 1;
+      ch = state.input.charCodeAt(++state.position);
     }
 
-    ch = state.input.charCodeAt(++state.position);
-  }
+    captureSegment(state, captureStart, captureEnd, false);
 
-  captureSegment(state, captureStart, captureEnd, false);
+    if (state.result) {
+      return true;
+    }
 
-  if (state.result) {
-    return true;
-  } else {
     state.kind = _kind;
     state.result = _result;
     return false;
   }
-}
-
-function readSingleQuotedScalar(state, nodeIndent) {
-  var ch,
-      captureStart, captureEnd;
 
-  ch = state.input.charCodeAt(state.position);
+  function readSingleQuotedScalar(state, nodeIndent) {
+    var ch,
+        captureStart, captureEnd;
 
-  if (0x27/* ' */ !== ch) {
-    return false;
-  }
+    ch = state.input.charCodeAt(state.position);
 
-  state.kind = 'scalar';
-  state.result = '';
-  state.position++;
-  captureStart = captureEnd = state.position;
+    if (0x27/* ' */ !== ch) {
+      return false;
+    }
 
-  while (0 !== (ch = state.input.charCodeAt(state.position))) {
-    if (0x27/* ' */ === ch) {
-      captureSegment(state, captureStart, state.position, true);
-      ch = state.input.charCodeAt(++state.position);
+    state.kind = 'scalar';
+    state.result = '';
+    state.position++;
+    captureStart = captureEnd = state.position;
 
+    while (0 !== (ch = state.input.charCodeAt(state.position))) {
       if (0x27/* ' */ === ch) {
+        captureSegment(state, captureStart, state.position, true);
+        ch = state.input.charCodeAt(++state.position);
+
+        if (0x27/* ' */ === ch) {
+          captureStart = captureEnd = state.position;
+          state.position++;
+        } else {
+          return true;
+        }
+
+      } else if (is_EOL(ch)) {
+        captureSegment(state, captureStart, captureEnd, true);
+        writeFoldedLines(state, skipSeparationSpace(state, false, nodeIndent));
         captureStart = captureEnd = state.position;
-        state.position++;
+
+      } else if (state.position === state.lineStart && testDocumentSeparator(state)) {
+        throwError(state, 'unexpected end of the document within a single quoted scalar');
+
       } else {
-        return true;
+        state.position++;
+        captureEnd = state.position;
       }
+    }
 
-    } else if (is_EOL(ch)) {
-      captureSegment(state, captureStart, captureEnd, true);
-      writeFoldedLines(state, skipSeparationSpace(state, false, nodeIndent));
-      captureStart = captureEnd = state.position;
+    throwError(state, 'unexpected end of the stream within a single quoted scalar');
+  }
 
-    } else if (state.position === state.lineStart && testDocumentSeparator(state)) {
-      throwError(state, 'unexpected end of the document within a single quoted scalar');
+  function readDoubleQuotedScalar(state, nodeIndent) {
+    var captureStart,
+        captureEnd,
+        hexLength,
+        hexResult,
+        tmp,
+        ch;
 
-    } else {
-      state.position++;
-      captureEnd = state.position;
-    }
-  }
+    ch = state.input.charCodeAt(state.position);
 
-  throwError(state, 'unexpected end of the stream within a single quoted scalar');
-}
+    if (0x22/* " */ !== ch) {
+      return false;
+    }
 
-function readDoubleQuotedScalar(state, nodeIndent) {
-  var captureStart,
-      captureEnd,
-      hexLength,
-      hexResult,
-      tmp, tmpEsc,
-      ch;
+    state.kind = 'scalar';
+    state.result = '';
+    state.position++;
+    captureStart = captureEnd = state.position;
 
-  ch = state.input.charCodeAt(state.position);
+    while (0 !== (ch = state.input.charCodeAt(state.position))) {
+      if (0x22/* " */ === ch) {
+        captureSegment(state, captureStart, state.position, true);
+        state.position++;
+        return true;
 
-  if (0x22/* " */ !== ch) {
-    return false;
-  }
+      } else if (0x5C/* \ */ === ch) {
+        captureSegment(state, captureStart, state.position, true);
+        ch = state.input.charCodeAt(++state.position);
 
-  state.kind = 'scalar';
-  state.result = '';
-  state.position++;
-  captureStart = captureEnd = state.position;
+        if (is_EOL(ch)) {
+          skipSeparationSpace(state, false, nodeIndent);
 
-  while (0 !== (ch = state.input.charCodeAt(state.position))) {
-    if (0x22/* " */ === ch) {
-      captureSegment(state, captureStart, state.position, true);
-      state.position++;
-      return true;
+          // TODO: rework to inline fn with no type cast?
+        } else if (ch < 256 && simpleEscapeCheck[ch]) {
+          state.result += simpleEscapeMap[ch];
+          state.position++;
 
-    } else if (0x5C/* \ */ === ch) {
-      captureSegment(state, captureStart, state.position, true);
-      ch = state.input.charCodeAt(++state.position);
+        } else if ((tmp = escapedHexLen(ch)) > 0) {
+          hexLength = tmp;
+          hexResult = 0;
 
-      if (is_EOL(ch)) {
-        skipSeparationSpace(state, false, nodeIndent);
+          for (; hexLength > 0; hexLength--) {
+            ch = state.input.charCodeAt(++state.position);
 
-        //TODO: rework to inline fn with no type cast?
-      } else if (ch < 256 && simpleEscapeCheck[ch]) {
-        state.result += simpleEscapeMap[ch];
-        state.position++;
+            if ((tmp = fromHexCode(ch)) >= 0) {
+              hexResult = (hexResult << 4) + tmp;
 
-      } else if ((tmp = escapedHexLen(ch)) > 0) {
-        hexLength = tmp;
-        hexResult = 0;
+            } else {
+              throwError(state, 'expected hexadecimal character');
+            }
+          }
 
-        for (; hexLength > 0; hexLength--) {
-          ch = state.input.charCodeAt(++state.position);
+          state.result += charFromCodepoint(hexResult);
 
-          if ((tmp = fromHexCode(ch)) >= 0) {
-            hexResult = (hexResult << 4) + tmp;
+          state.position++;
 
-          } else {
-            throwError(state, 'expected hexadecimal character');
-          }
+        } else {
+          throwError(state, 'unknown escape sequence');
         }
 
-        state.result += charFromCodepoint(hexResult);
+        captureStart = captureEnd = state.position;
 
-        state.position++;
+      } else if (is_EOL(ch)) {
+        captureSegment(state, captureStart, captureEnd, true);
+        writeFoldedLines(state, skipSeparationSpace(state, false, nodeIndent));
+        captureStart = captureEnd = state.position;
+
+      } else if (state.position === state.lineStart && testDocumentSeparator(state)) {
+        throwError(state, 'unexpected end of the document within a double quoted scalar');
 
       } else {
-        throwError(state, 'unknown escape sequence');
+        state.position++;
+        captureEnd = state.position;
       }
+    }
 
-      captureStart = captureEnd = state.position;
+    throwError(state, 'unexpected end of the stream within a double quoted scalar');
+  }
 
-    } else if (is_EOL(ch)) {
-      captureSegment(state, captureStart, captureEnd, true);
-      writeFoldedLines(state, skipSeparationSpace(state, false, nodeIndent));
-      captureStart = captureEnd = state.position;
+  function readFlowCollection(state, nodeIndent) {
+    var readNext = true,
+        _line,
+        _tag     = state.tag,
+        _result,
+        _anchor  = state.anchor,
+        following,
+        terminator,
+        isPair,
+        isExplicitPair,
+        isMapping,
+        overridableKeys = {},
+        keyNode,
+        keyTag,
+        valueNode,
+        ch;
 
-    } else if (state.position === state.lineStart && testDocumentSeparator(state)) {
-      throwError(state, 'unexpected end of the document within a double quoted scalar');
+    ch = state.input.charCodeAt(state.position);
 
+    if (ch === 0x5B/* [ */) {
+      terminator = 0x5D;/* ] */
+      isMapping = false;
+      _result = [];
+    } else if (ch === 0x7B/* { */) {
+      terminator = 0x7D;/* } */
+      isMapping = true;
+      _result = {};
     } else {
-      state.position++;
-      captureEnd = state.position;
-    }
-  }
-
-  throwError(state, 'unexpected end of the stream within a double quoted scalar');
-}
-
-function readFlowCollection(state, nodeIndent) {
-  var readNext = true,
-      _line,
-      _tag     = state.tag,
-      _result,
-      _anchor  = state.anchor,
-      following,
-      terminator,
-      isPair,
-      isExplicitPair,
-      isMapping,
-      keyNode,
-      keyTag,
-      valueNode,
-      ch;
-
-  ch = state.input.charCodeAt(state.position);
-
-  if (ch === 0x5B/* [ */) {
-    terminator = 0x5D/* ] */;
-    isMapping = false;
-    _result = [];
-  } else if (ch === 0x7B/* { */) {
-    terminator = 0x7D/* } */;
-    isMapping = true;
-    _result = {};
-  } else {
-    return false;
-  }
+      return false;
+    }
 
-  if (null !== state.anchor) {
-    state.anchorMap[state.anchor] = _result;
-  }
+    if (null !== state.anchor) {
+      state.anchorMap[state.anchor] = _result;
+    }
 
-  ch = state.input.charCodeAt(++state.position);
+    ch = state.input.charCodeAt(++state.position);
 
-  while (0 !== ch) {
-    skipSeparationSpace(state, true, nodeIndent);
+    while (0 !== ch) {
+      skipSeparationSpace(state, true, nodeIndent);
 
-    ch = state.input.charCodeAt(state.position);
+      ch = state.input.charCodeAt(state.position);
 
-    if (ch === terminator) {
-      state.position++;
-      state.tag = _tag;
-      state.anchor = _anchor;
-      state.kind = isMapping ? 'mapping' : 'sequence';
-      state.result = _result;
-      return true;
-    } else if (!readNext) {
-      throwError(state, 'missed comma between flow collection entries');
-    }
+      if (ch === terminator) {
+        state.position++;
+        state.tag = _tag;
+        state.anchor = _anchor;
+        state.kind = isMapping ? 'mapping' : 'sequence';
+        state.result = _result;
+        return true;
+      } else if (!readNext) {
+        throwError(state, 'missed comma between flow collection entries');
+      }
 
-    keyTag = keyNode = valueNode = null;
-    isPair = isExplicitPair = false;
+      keyTag = keyNode = valueNode = null;
+      isPair = isExplicitPair = false;
 
-    if (0x3F/* ? */ === ch) {
-      following = state.input.charCodeAt(state.position + 1);
+      if (0x3F/* ? */ === ch) {
+        following = state.input.charCodeAt(state.position + 1);
 
-      if (is_WS_OR_EOL(following)) {
-        isPair = isExplicitPair = true;
-        state.position++;
-        skipSeparationSpace(state, true, nodeIndent);
+        if (is_WS_OR_EOL(following)) {
+          isPair = isExplicitPair = true;
+          state.position++;
+          skipSeparationSpace(state, true, nodeIndent);
+        }
       }
-    }
 
-    _line = state.line;
-    composeNode(state, nodeIndent, CONTEXT_FLOW_IN, false, true);
-    keyTag = state.tag;
-    keyNode = state.result;
-    skipSeparationSpace(state, true, nodeIndent);
+      _line = state.line;
+      composeNode(state, nodeIndent, CONTEXT_FLOW_IN, false, true);
+      keyTag = state.tag;
+      keyNode = state.result;
+      skipSeparationSpace(state, true, nodeIndent);
 
-    ch = state.input.charCodeAt(state.position);
+      ch = state.input.charCodeAt(state.position);
 
-    if ((isExplicitPair || state.line === _line) && 0x3A/* : */ === ch) {
-      isPair = true;
-      ch = state.input.charCodeAt(++state.position);
-      skipSeparationSpace(state, true, nodeIndent);
-      composeNode(state, nodeIndent, CONTEXT_FLOW_IN, false, true);
-      valueNode = state.result;
-    }
+      if ((isExplicitPair || state.line === _line) && 0x3A/* : */ === ch) {
+        isPair = true;
+        ch = state.input.charCodeAt(++state.position);
+        skipSeparationSpace(state, true, nodeIndent);
+        composeNode(state, nodeIndent, CONTEXT_FLOW_IN, false, true);
+        valueNode = state.result;
+      }
 
-    if (isMapping) {
-      storeMappingPair(state, _result, keyTag, keyNode, valueNode);
-    } else if (isPair) {
-      _result.push(storeMappingPair(state, null, keyTag, keyNode, valueNode));
-    } else {
-      _result.push(keyNode);
-    }
+      if (isMapping) {
+        storeMappingPair(state, _result, overridableKeys, keyTag, keyNode, valueNode);
+      } else if (isPair) {
+        _result.push(storeMappingPair(state, null, overridableKeys, keyTag, keyNode, valueNode));
+      } else {
+        _result.push(keyNode);
+      }
 
-    skipSeparationSpace(state, true, nodeIndent);
+      skipSeparationSpace(state, true, nodeIndent);
 
-    ch = state.input.charCodeAt(state.position);
+      ch = state.input.charCodeAt(state.position);
 
-    if (0x2C/* , */ === ch) {
-      readNext = true;
-      ch = state.input.charCodeAt(++state.position);
-    } else {
-      readNext = false;
+      if (0x2C/* , */ === ch) {
+        readNext = true;
+        ch = state.input.charCodeAt(++state.position);
+      } else {
+        readNext = false;
+      }
     }
+
+    throwError(state, 'unexpected end of the stream within a flow collection');
   }
 
-  throwError(state, 'unexpected end of the stream within a flow collection');
-}
+  function readBlockScalar(state, nodeIndent) {
+    var captureStart,
+        folding,
+        chomping       = CHOMPING_CLIP,
+        detectedIndent = false,
+        textIndent     = nodeIndent,
+        emptyLines     = 0,
+        atMoreIndented = false,
+        tmp,
+        ch;
 
-function readBlockScalar(state, nodeIndent) {
-  var captureStart,
-      folding,
-      chomping       = CHOMPING_CLIP,
-      detectedIndent = false,
-      textIndent     = nodeIndent,
-      emptyLines     = 0,
-      atMoreIndented = false,
-      tmp,
-      ch;
+    ch = state.input.charCodeAt(state.position);
 
-  ch = state.input.charCodeAt(state.position);
+    if (ch === 0x7C/* | */) {
+      folding = false;
+    } else if (ch === 0x3E/* > */) {
+      folding = true;
+    } else {
+      return false;
+    }
 
-  if (ch === 0x7C/* | */) {
-    folding = false;
-  } else if (ch === 0x3E/* > */) {
-    folding = true;
-  } else {
-    return false;
-  }
+    state.kind = 'scalar';
+    state.result = '';
 
-  state.kind = 'scalar';
-  state.result = '';
+    while (0 !== ch) {
+      ch = state.input.charCodeAt(++state.position);
 
-  while (0 !== ch) {
-    ch = state.input.charCodeAt(++state.position);
+      if (0x2B/* + */ === ch || 0x2D/* - */ === ch) {
+        if (CHOMPING_CLIP === chomping) {
+          chomping = (0x2B/* + */ === ch) ? CHOMPING_KEEP : CHOMPING_STRIP;
+        } else {
+          throwError(state, 'repeat of 

<TRUNCATED>