datapackage/dist/datapackage.js

Utilities to work with Data Packages as defined on specs.frictionlessdata.io

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	if(typeof exports === 'object' && typeof module === 'object')
		module.exports = factory();
	else if(typeof define === 'function' && define.amd)
		define([], factory);
	else if(typeof exports === 'object')
		exports["datapackage"] = factory();
	else
		root["datapackage"] = factory();
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/* 0 */
/***/ (function(module, exports, __webpack_require__) {

var baseGetTag = __webpack_require__(7),
    isArray = __webpack_require__(1),
    isObjectLike = __webpack_require__(4);

/** `Object#toString` result references. */
var stringTag = '[object String]';

/**
 * Checks if `value` is classified as a `String` primitive or object.
 *
 * @static
 * @since 0.1.0
 * @memberOf _
 * @category Lang
 * @param {*} value The value to check.
 * @returns {boolean} Returns `true` if `value` is a string, else `false`.
 * @example
 *
 * _.isString('abc');
 * // => true
 *
 * _.isString(1);
 * // => false
 */
function isString(value) {
  return typeof value == 'string' ||
    (!isArray(value) && isObjectLike(value) && baseGetTag(value) == stringTag);
}

module.exports = isString;


/***/ }),
/* 1 */
/***/ (function(module, exports) {

/**
 * Checks if `value` is classified as an `Array` object.
 *
 * @static
 * @memberOf _
 * @since 0.1.0
 * @category Lang
 * @param {*} value The value to check.
 * @returns {boolean} Returns `true` if `value` is an array, else `false`.
 * @example
 *
 * _.isArray([1, 2, 3]);
 * // => true
 *
 * _.isArray(document.body.children);
 * // => false
 *
 * _.isArray('abc');
 * // => false
 *
 * _.isArray(_.noop);
 * // => false
 */
var isArray = Array.isArray;

module.exports = isArray;


/***/ }),
/* 2 */
/***/ (function(module, exports, __webpack_require__) {

"use strict";


// Module API

var ERROR = 'tableschema.error';
var INFER_THRESHOLD = 10;
var INFER_CONFIDENCE = 0.75;
var DEFAULT_FORMAT = 'csv';
var DEFAULT_ENCODING = 'utf-8';
var DEFAULT_FIELD_TYPE = 'string';
var DEFAULT_FIELD_FORMAT = 'default';
var DEFAULT_MISSING_VALUES = [''];
var IS_BROWSER = typeof window !== 'undefined';

// System

module.exports = {
  ERROR: ERROR,
  INFER_THRESHOLD: INFER_THRESHOLD,
  INFER_CONFIDENCE: INFER_CONFIDENCE,
  DEFAULT_FORMAT: DEFAULT_FORMAT,
  DEFAULT_ENCODING: DEFAULT_ENCODING,
  DEFAULT_FIELD_TYPE: DEFAULT_FIELD_TYPE,
  DEFAULT_FIELD_FORMAT: DEFAULT_FIELD_FORMAT,
  DEFAULT_MISSING_VALUES: DEFAULT_MISSING_VALUES,
  IS_BROWSER: IS_BROWSER
};

/***/ }),
/* 3 */
/***/ (function(module, exports, __webpack_require__) {

var freeGlobal = __webpack_require__(117);

/** Detect free variable `self`. */
var freeSelf = typeof self == 'object' && self && self.Object === Object && self;

/** Used as a reference to the global object. */
var root = freeGlobal || freeSelf || Function('return this')();

module.exports = root;


/***/ }),
/* 4 */
/***/ (function(module, exports) {

/**
 * Checks if `value` is object-like. A value is object-like if it's not `null`
 * and has a `typeof` result of "object".
 *
 * @static
 * @memberOf _
 * @since 4.0.0
 * @category Lang
 * @param {*} value The value to check.
 * @returns {boolean} Returns `true` if `value` is object-like, else `false`.
 * @example
 *
 * _.isObjectLike({});
 * // => true
 *
 * _.isObjectLike([1, 2, 3]);
 * // => true
 *
 * _.isObjectLike(_.noop);
 * // => false
 *
 * _.isObjectLike(null);
 * // => false
 */
function isObjectLike(value) {
  return value != null && typeof value == 'object';
}

module.exports = isObjectLike;


/***/ }),
/* 5 */
/***/ (function(module, exports, __webpack_require__) {

"use strict";


var bind = __webpack_require__(92);

/*global toString:true*/

// utils is a library of generic helper functions non-specific to axios

var toString = Object.prototype.toString;

/**
 * Determine if a value is an Array
 *
 * @param {Object} val The value to test
 * @returns {boolean} True if value is an Array, otherwise false
 */
function isArray(val) {
  return toString.call(val) === '[object Array]';
}

/**
 * Determine if a value is undefined
 *
 * @param {Object} val The value to test
 * @returns {boolean} True if the value is undefined, otherwise false
 */
function isUndefined(val) {
  return typeof val === 'undefined';
}

/**
 * Determine if a value is a Buffer
 *
 * @param {Object} val The value to test
 * @returns {boolean} True if value is a Buffer, otherwise false
 */
function isBuffer(val) {
  return val !== null && !isUndefined(val) && val.constructor !== null && !isUndefined(val.constructor)
    && typeof val.constructor.isBuffer === 'function' && val.constructor.isBuffer(val);
}

/**
 * Determine if a value is an ArrayBuffer
 *
 * @param {Object} val The value to test
 * @returns {boolean} True if value is an ArrayBuffer, otherwise false
 */
function isArrayBuffer(val) {
  return toString.call(val) === '[object ArrayBuffer]';
}

/**
 * Determine if a value is a FormData
 *
 * @param {Object} val The value to test
 * @returns {boolean} True if value is an FormData, otherwise false
 */
function isFormData(val) {
  return (typeof FormData !== 'undefined') && (val instanceof FormData);
}

/**
 * Determine if a value is a view on an ArrayBuffer
 *
 * @param {Object} val The value to test
 * @returns {boolean} True if value is a view on an ArrayBuffer, otherwise false
 */
function isArrayBufferView(val) {
  var result;
  if ((typeof ArrayBuffer !== 'undefined') && (ArrayBuffer.isView)) {
    result = ArrayBuffer.isView(val);
  } else {
    result = (val) && (val.buffer) && (val.buffer instanceof ArrayBuffer);
  }
  return result;
}

/**
 * Determine if a value is a String
 *
 * @param {Object} val The value to test
 * @returns {boolean} True if value is a String, otherwise false
 */
function isString(val) {
  return typeof val === 'string';
}

/**
 * Determine if a value is a Number
 *
 * @param {Object} val The value to test
 * @returns {boolean} True if value is a Number, otherwise false
 */
function isNumber(val) {
  return typeof val === 'number';
}

/**
 * Determine if a value is an Object
 *
 * @param {Object} val The value to test
 * @returns {boolean} True if value is an Object, otherwise false
 */
function isObject(val) {
  return val !== null && typeof val === 'object';
}

/**
 * Determine if a value is a plain Object
 *
 * @param {Object} val The value to test
 * @return {boolean} True if value is a plain Object, otherwise false
 */
function isPlainObject(val) {
  if (toString.call(val) !== '[object Object]') {
    return false;
  }

  var prototype = Object.getPrototypeOf(val);
  return prototype === null || prototype === Object.prototype;
}

/**
 * Determine if a value is a Date
 *
 * @param {Object} val The value to test
 * @returns {boolean} True if value is a Date, otherwise false
 */
function isDate(val) {
  return toString.call(val) === '[object Date]';
}

/**
 * Determine if a value is a File
 *
 * @param {Object} val The value to test
 * @returns {boolean} True if value is a File, otherwise false
 */
function isFile(val) {
  return toString.call(val) === '[object File]';
}

/**
 * Determine if a value is a Blob
 *
 * @param {Object} val The value to test
 * @returns {boolean} True if value is a Blob, otherwise false
 */
function isBlob(val) {
  return toString.call(val) === '[object Blob]';
}

/**
 * Determine if a value is a Function
 *
 * @param {Object} val The value to test
 * @returns {boolean} True if value is a Function, otherwise false
 */
function isFunction(val) {
  return toString.call(val) === '[object Function]';
}

/**
 * Determine if a value is a Stream
 *
 * @param {Object} val The value to test
 * @returns {boolean} True if value is a Stream, otherwise false
 */
function isStream(val) {
  return isObject(val) && isFunction(val.pipe);
}

/**
 * Determine if a value is a URLSearchParams object
 *
 * @param {Object} val The value to test
 * @returns {boolean} True if value is a URLSearchParams object, otherwise false
 */
function isURLSearchParams(val) {
  return typeof URLSearchParams !== 'undefined' && val instanceof URLSearchParams;
}

/**
 * Trim excess whitespace off the beginning and end of a string
 *
 * @param {String} str The String to trim
 * @returns {String} The String freed of excess whitespace
 */
function trim(str) {
  return str.replace(/^\s*/, '').replace(/\s*$/, '');
}

/**
 * Determine if we're running in a standard browser environment
 *
 * This allows axios to run in a web worker, and react-native.
 * Both environments support XMLHttpRequest, but not fully standard globals.
 *
 * web workers:
 *  typeof window -> undefined
 *  typeof document -> undefined
 *
 * react-native:
 *  navigator.product -> 'ReactNative'
 * nativescript
 *  navigator.product -> 'NativeScript' or 'NS'
 */
function isStandardBrowserEnv() {
  if (typeof navigator !== 'undefined' && (navigator.product === 'ReactNative' ||
                                           navigator.product === 'NativeScript' ||
                                           navigator.product === 'NS')) {
    return false;
  }
  return (
    typeof window !== 'undefined' &&
    typeof document !== 'undefined'
  );
}

/**
 * Iterate over an Array or an Object invoking a function for each item.
 *
 * If `obj` is an Array callback will be called passing
 * the value, index, and complete array for each item.
 *
 * If 'obj' is an Object callback will be called passing
 * the value, key, and complete object for each property.
 *
 * @param {Object|Array} obj The object to iterate
 * @param {Function} fn The callback to invoke for each item
 */
function forEach(obj, fn) {
  // Don't bother if no value provided
  if (obj === null || typeof obj === 'undefined') {
    return;
  }

  // Force an array if not already something iterable
  if (typeof obj !== 'object') {
    /*eslint no-param-reassign:0*/
    obj = [obj];
  }

  if (isArray(obj)) {
    // Iterate over array values
    for (var i = 0, l = obj.length; i < l; i++) {
      fn.call(null, obj[i], i, obj);
    }
  } else {
    // Iterate over object keys
    for (var key in obj) {
      if (Object.prototype.hasOwnProperty.call(obj, key)) {
        fn.call(null, obj[key], key, obj);
      }
    }
  }
}

/**
 * Accepts varargs expecting each argument to be an object, then
 * immutably merges the properties of each object and returns result.
 *
 * When multiple objects contain the same key the later object in
 * the arguments list will take precedence.
 *
 * Example:
 *
 * ```js
 * var result = merge({foo: 123}, {foo: 456});
 * console.log(result.foo); // outputs 456
 * ```
 *
 * @param {Object} obj1 Object to merge
 * @returns {Object} Result of all merge properties
 */
function merge(/* obj1, obj2, obj3, ... */) {
  var result = {};
  function assignValue(val, key) {
    if (isPlainObject(result[key]) && isPlainObject(val)) {
      result[key] = merge(result[key], val);
    } else if (isPlainObject(val)) {
      result[key] = merge({}, val);
    } else if (isArray(val)) {
      result[key] = val.slice();
    } else {
      result[key] = val;
    }
  }

  for (var i = 0, l = arguments.length; i < l; i++) {
    forEach(arguments[i], assignValue);
  }
  return result;
}

/**
 * Extends object a by mutably adding to it the properties of object b.
 *
 * @param {Object} a The object to be extended
 * @param {Object} b The object to copy properties from
 * @param {Object} thisArg The object to bind function to
 * @return {Object} The resulting value of object a
 */
function extend(a, b, thisArg) {
  forEach(b, function assignValue(val, key) {
    if (thisArg && typeof val === 'function') {
      a[key] = bind(val, thisArg);
    } else {
      a[key] = val;
    }
  });
  return a;
}

/**
 * Remove byte order marker. This catches EF BB BF (the UTF-8 BOM)
 *
 * @param {string} content with BOM
 * @return {string} content value without BOM
 */
function stripBOM(content) {
  if (content.charCodeAt(0) === 0xFEFF) {
    content = content.slice(1);
  }
  return content;
}

module.exports = {
  isArray: isArray,
  isArrayBuffer: isArrayBuffer,
  isBuffer: isBuffer,
  isFormData: isFormData,
  isArrayBufferView: isArrayBufferView,
  isString: isString,
  isNumber: isNumber,
  isObject: isObject,
  isPlainObject: isPlainObject,
  isUndefined: isUndefined,
  isDate: isDate,
  isFile: isFile,
  isBlob: isBlob,
  isFunction: isFunction,
  isStream: isStream,
  isURLSearchParams: isURLSearchParams,
  isStandardBrowserEnv: isStandardBrowserEnv,
  forEach: forEach,
  merge: merge,
  extend: extend,
  trim: trim,
  stripBOM: stripBOM
};


/***/ }),
/* 6 */
/***/ (function(module, exports) {

/**
 * Checks if `value` is the
 * [language type](http://www.ecma-international.org/ecma-262/7.0/#sec-ecmascript-language-types)
 * of `Object`. (e.g. arrays, functions, objects, regexes, `new Number(0)`, and `new String('')`)
 *
 * @static
 * @memberOf _
 * @since 0.1.0
 * @category Lang
 * @param {*} value The value to check.
 * @returns {boolean} Returns `true` if `value` is an object, else `false`.
 * @example
 *
 * _.isObject({});
 * // => true
 *
 * _.isObject([1, 2, 3]);
 * // => true
 *
 * _.isObject(_.noop);
 * // => true
 *
 * _.isObject(null);
 * // => false
 */
function isObject(value) {
  var type = typeof value;
  return value != null && (type == 'object' || type == 'function');
}

module.exports = isObject;


/***/ }),
/* 7 */
/***/ (function(module, exports, __webpack_require__) {

var Symbol = __webpack_require__(18),
    getRawTag = __webpack_require__(244),
    objectToString = __webpack_require__(278);

/** `Object#toString` result references. */
var nullTag = '[object Null]',
    undefinedTag = '[object Undefined]';

/** Built-in value references. */
var symToStringTag = Symbol ? Symbol.toStringTag : undefined;

/**
 * The base implementation of `getTag` without fallbacks for buggy environments.
 *
 * @private
 * @param {*} value The value to query.
 * @returns {string} Returns the `toStringTag`.
 */
function baseGetTag(value) {
  if (value == null) {
    return value === undefined ? undefinedTag : nullTag;
  }
  return (symToStringTag && symToStringTag in Object(value))
    ? getRawTag(value)
    : objectToString(value);
}

module.exports = baseGetTag;


/***/ }),
/* 8 */
/***/ (function(module, exports) {

// shim for using process in browser
var process = module.exports = {};

// cached from whatever global is present so that test runners that stub it
// don't break things.  But we need to wrap it in a try catch in case it is
// wrapped in strict mode code which doesn't define any globals.  It's inside a
// function because try/catches deoptimize in certain engines.

var cachedSetTimeout;
var cachedClearTimeout;

function defaultSetTimout() {
    throw new Error('setTimeout has not been defined');
}
function defaultClearTimeout () {
    throw new Error('clearTimeout has not been defined');
}
(function () {
    try {
        if (typeof setTimeout === 'function') {
            cachedSetTimeout = setTimeout;
        } else {
            cachedSetTimeout = defaultSetTimout;
        }
    } catch (e) {
        cachedSetTimeout = defaultSetTimout;
    }
    try {
        if (typeof clearTimeout === 'function') {
            cachedClearTimeout = clearTimeout;
        } else {
            cachedClearTimeout = defaultClearTimeout;
        }
    } catch (e) {
        cachedClearTimeout = defaultClearTimeout;
    }
} ())
function runTimeout(fun) {
    if (cachedSetTimeout === setTimeout) {
        //normal enviroments in sane situations
        return setTimeout(fun, 0);
    }
    // if setTimeout wasn't available but was latter defined
    if ((cachedSetTimeout === defaultSetTimout || !cachedSetTimeout) && setTimeout) {
        cachedSetTimeout = setTimeout;
        return setTimeout(fun, 0);
    }
    try {
        // when when somebody has screwed with setTimeout but no I.E. maddness
        return cachedSetTimeout(fun, 0);
    } catch(e){
        try {
            // When we are in I.E. but the script has been evaled so I.E. doesn't trust the global object when called normally
            return cachedSetTimeout.call(null, fun, 0);
        } catch(e){
            // same as above but when it's a version of I.E. that must have the global object for 'this', hopfully our context correct otherwise it will throw a global error
            return cachedSetTimeout.call(this, fun, 0);
        }
    }


}
function runClearTimeout(marker) {
    if (cachedClearTimeout === clearTimeout) {
        //normal enviroments in sane situations
        return clearTimeout(marker);
    }
    // if clearTimeout wasn't available but was latter defined
    if ((cachedClearTimeout === defaultClearTimeout || !cachedClearTimeout) && clearTimeout) {
        cachedClearTimeout = clearTimeout;
        return clearTimeout(marker);
    }
    try {
        // when when somebody has screwed with setTimeout but no I.E. maddness
        return cachedClearTimeout(marker);
    } catch (e){
        try {
            // When we are in I.E. but the script has been evaled so I.E. doesn't  trust the global object when called normally
            return cachedClearTimeout.call(null, marker);
        } catch (e){
            // same as above but when it's a version of I.E. that must have the global object for 'this', hopfully our context correct otherwise it will throw a global error.
            // Some versions of I.E. have different rules for clearTimeout vs setTimeout
            return cachedClearTimeout.call(this, marker);
        }
    }



}
var queue = [];
var draining = false;
var currentQueue;
var queueIndex = -1;

function cleanUpNextTick() {
    if (!draining || !currentQueue) {
        return;
    }
    draining = false;
    if (currentQueue.length) {
        queue = currentQueue.concat(queue);
    } else {
        queueIndex = -1;
    }
    if (queue.length) {
        drainQueue();
    }
}

function drainQueue() {
    if (draining) {
        return;
    }
    var timeout = runTimeout(cleanUpNextTick);
    draining = true;

    var len = queue.length;
    while(len) {
        currentQueue = queue;
        queue = [];
        while (++queueIndex < len) {
            if (currentQueue) {
                currentQueue[queueIndex].run();
            }
        }
        queueIndex = -1;
        len = queue.length;
    }
    currentQueue = null;
    draining = false;
    runClearTimeout(timeout);
}

process.nextTick = function (fun) {
    var args = new Array(arguments.length - 1);
    if (arguments.length > 1) {
        for (var i = 1; i < arguments.length; i++) {
            args[i - 1] = arguments[i];
        }
    }
    queue.push(new Item(fun, args));
    if (queue.length === 1 && !draining) {
        runTimeout(drainQueue);
    }
};

// v8 likes predictible objects
function Item(fun, array) {
    this.fun = fun;
    this.array = array;
}
Item.prototype.run = function () {
    this.fun.apply(null, this.array);
};
process.title = 'browser';
process.browser = true;
process.env = {};
process.argv = [];
process.version = ''; // empty string to avoid regexp issues
process.versions = {};

function noop() {}

process.on = noop;
process.addListener = noop;
process.once = noop;
process.off = noop;
process.removeListener = noop;
process.removeAllListeners = noop;
process.emit = noop;
process.prependListener = noop;
process.prependOnceListener = noop;

process.listeners = function (name) { return [] }

process.binding = function (name) {
    throw new Error('process.binding is not supported');
};

process.cwd = function () { return '/' };
process.chdir = function (dir) {
    throw new Error('process.chdir is not supported');
};
process.umask = function() { return 0; };


/***/ }),
/* 9 */
/***/ (function(module, exports) {



/***/ }),
/* 10 */
/***/ (function(module, exports) {

var g;

// This works in non-strict mode
g = (function() {
	return this;
})();

try {
	// This works if eval is allowed (see CSP)
	g = g || Function("return this")() || (1,eval)("this");
} catch(e) {
	// This works if the window reference is available
	if(typeof window === "object")
		g = window;
}

// g can still be undefined, but nothing to do about it...
// We return undefined, instead of nothing here, so it's
// easier to handle this case. if(!global) { ...}

module.exports = g;


/***/ }),
/* 11 */
/***/ (function(module, exports, __webpack_require__) {

"use strict";


var tableschema = __webpack_require__(148);

// Module API

/**
 * Base class for the all DataPackage errors.
 */
var DataPackageError = tableschema.errors.DataPackageError;

/**
 * Base class for the all TableSchema errors.
 */
var TableSchemaError = tableschema.errors.TableSchemaError;

// System

module.exports = {
  DataPackageError: DataPackageError,
  TableSchemaError: TableSchemaError
};

/***/ }),
/* 12 */
/***/ (function(module, exports, __webpack_require__) {

"use strict";
/* WEBPACK VAR INJECTION */(function(global) {/*!
 * The buffer module from node.js, for the browser.
 *
 * @author   Feross Aboukhadijeh <http://feross.org>
 * @license  MIT
 */
/* eslint-disable no-proto */



var base64 = __webpack_require__(174)
var ieee754 = __webpack_require__(179)
var isArray = __webpack_require__(95)

exports.Buffer = Buffer
exports.SlowBuffer = SlowBuffer
exports.INSPECT_MAX_BYTES = 50

/**
 * If `Buffer.TYPED_ARRAY_SUPPORT`:
 *   === true    Use Uint8Array implementation (fastest)
 *   === false   Use Object implementation (most compatible, even IE6)
 *
 * Browsers that support typed arrays are IE 10+, Firefox 4+, Chrome 7+, Safari 5.1+,
 * Opera 11.6+, iOS 4.2+.
 *
 * Due to various browser bugs, sometimes the Object implementation will be used even
 * when the browser supports typed arrays.
 *
 * Note:
 *
 *   - Firefox 4-29 lacks support for adding new properties to `Uint8Array` instances,
 *     See: https://bugzilla.mozilla.org/show_bug.cgi?id=695438.
 *
 *   - Chrome 9-10 is missing the `TypedArray.prototype.subarray` function.
 *
 *   - IE10 has a broken `TypedArray.prototype.subarray` function which returns arrays of
 *     incorrect length in some situations.

 * We detect these buggy browsers and set `Buffer.TYPED_ARRAY_SUPPORT` to `false` so they
 * get the Object implementation, which is slower but behaves correctly.
 */
Buffer.TYPED_ARRAY_SUPPORT = global.TYPED_ARRAY_SUPPORT !== undefined
  ? global.TYPED_ARRAY_SUPPORT
  : typedArraySupport()

/*
 * Export kMaxLength after typed array support is determined.
 */
exports.kMaxLength = kMaxLength()

function typedArraySupport () {
  try {
    var arr = new Uint8Array(1)
    arr.__proto__ = {__proto__: Uint8Array.prototype, foo: function () { return 42 }}
    return arr.foo() === 42 && // typed array instances can be augmented
        typeof arr.subarray === 'function' && // chrome 9-10 lack `subarray`
        arr.subarray(1, 1).byteLength === 0 // ie10 has broken `subarray`
  } catch (e) {
    return false
  }
}

function kMaxLength () {
  return Buffer.TYPED_ARRAY_SUPPORT
    ? 0x7fffffff
    : 0x3fffffff
}

function createBuffer (that, length) {
  if (kMaxLength() < length) {
    throw new RangeError('Invalid typed array length')
  }
  if (Buffer.TYPED_ARRAY_SUPPORT) {
    // Return an augmented `Uint8Array` instance, for best performance
    that = new Uint8Array(length)
    that.__proto__ = Buffer.prototype
  } else {
    // Fallback: Return an object instance of the Buffer class
    if (that === null) {
      that = new Buffer(length)
    }
    that.length = length
  }

  return that
}

/**
 * The Buffer constructor returns instances of `Uint8Array` that have their
 * prototype changed to `Buffer.prototype`. Furthermore, `Buffer` is a subclass of
 * `Uint8Array`, so the returned instances will have all the node `Buffer` methods
 * and the `Uint8Array` methods. Square bracket notation works as expected -- it
 * returns a single octet.
 *
 * The `Uint8Array` prototype remains unmodified.
 */

function Buffer (arg, encodingOrOffset, length) {
  if (!Buffer.TYPED_ARRAY_SUPPORT && !(this instanceof Buffer)) {
    return new Buffer(arg, encodingOrOffset, length)
  }

  // Common case.
  if (typeof arg === 'number') {
    if (typeof encodingOrOffset === 'string') {
      throw new Error(
        'If encoding is specified then the first argument must be a string'
      )
    }
    return allocUnsafe(this, arg)
  }
  return from(this, arg, encodingOrOffset, length)
}

Buffer.poolSize = 8192 // not used by this implementation

// TODO: Legacy, not needed anymore. Remove in next major version.
Buffer._augment = function (arr) {
  arr.__proto__ = Buffer.prototype
  return arr
}

function from (that, value, encodingOrOffset, length) {
  if (typeof value === 'number') {
    throw new TypeError('"value" argument must not be a number')
  }

  if (typeof ArrayBuffer !== 'undefined' && value instanceof ArrayBuffer) {
    return fromArrayBuffer(that, value, encodingOrOffset, length)
  }

  if (typeof value === 'string') {
    return fromString(that, value, encodingOrOffset)
  }

  return fromObject(that, value)
}

/**
 * Functionally equivalent to Buffer(arg, encoding) but throws a TypeError
 * if value is a number.
 * Buffer.from(str[, encoding])
 * Buffer.from(array)
 * Buffer.from(buffer)
 * Buffer.from(arrayBuffer[, byteOffset[, length]])
 **/
Buffer.from = function (value, encodingOrOffset, length) {
  return from(null, value, encodingOrOffset, length)
}

if (Buffer.TYPED_ARRAY_SUPPORT) {
  Buffer.prototype.__proto__ = Uint8Array.prototype
  Buffer.__proto__ = Uint8Array
  if (typeof Symbol !== 'undefined' && Symbol.species &&
      Buffer[Symbol.species] === Buffer) {
    // Fix subarray() in ES2016. See: https://github.com/feross/buffer/pull/97
    Object.defineProperty(Buffer, Symbol.species, {
      value: null,
      configurable: true
    })
  }
}

function assertSize (size) {
  if (typeof size !== 'number') {
    throw new TypeError('"size" argument must be a number')
  } else if (size < 0) {
    throw new RangeError('"size" argument must not be negative')
  }
}

function alloc (that, size, fill, encoding) {
  assertSize(size)
  if (size <= 0) {
    return createBuffer(that, size)
  }
  if (fill !== undefined) {
    // Only pay attention to encoding if it's a string. This
    // prevents accidentally sending in a number that would
    // be interpretted as a start offset.
    return typeof encoding === 'string'
      ? createBuffer(that, size).fill(fill, encoding)
      : createBuffer(that, size).fill(fill)
  }
  return createBuffer(that, size)
}

/**
 * Creates a new filled Buffer instance.
 * alloc(size[, fill[, encoding]])
 **/
Buffer.alloc = function (size, fill, encoding) {
  return alloc(null, size, fill, encoding)
}

function allocUnsafe (that, size) {
  assertSize(size)
  that = createBuffer(that, size < 0 ? 0 : checked(size) | 0)
  if (!Buffer.TYPED_ARRAY_SUPPORT) {
    for (var i = 0; i < size; ++i) {
      that[i] = 0
    }
  }
  return that
}

/**
 * Equivalent to Buffer(num), by default creates a non-zero-filled Buffer instance.
 * */
Buffer.allocUnsafe = function (size) {
  return allocUnsafe(null, size)
}
/**
 * Equivalent to SlowBuffer(num), by default creates a non-zero-filled Buffer instance.
 */
Buffer.allocUnsafeSlow = function (size) {
  return allocUnsafe(null, size)
}

function fromString (that, string, encoding) {
  if (typeof encoding !== 'string' || encoding === '') {
    encoding = 'utf8'
  }

  if (!Buffer.isEncoding(encoding)) {
    throw new TypeError('"encoding" must be a valid string encoding')
  }

  var length = byteLength(string, encoding) | 0
  that = createBuffer(that, length)

  var actual = that.write(string, encoding)

  if (actual !== length) {
    // Writing a hex string, for example, that contains invalid characters will
    // cause everything after the first invalid character to be ignored. (e.g.
    // 'abxxcd' will be treated as 'ab')
    that = that.slice(0, actual)
  }

  return that
}

function fromArrayLike (that, array) {
  var length = array.length < 0 ? 0 : checked(array.length) | 0
  that = createBuffer(that, length)
  for (var i = 0; i < length; i += 1) {
    that[i] = array[i] & 255
  }
  return that
}

function fromArrayBuffer (that, array, byteOffset, length) {
  array.byteLength // this throws if `array` is not a valid ArrayBuffer

  if (byteOffset < 0 || array.byteLength < byteOffset) {
    throw new RangeError('\'offset\' is out of bounds')
  }

  if (array.byteLength < byteOffset + (length || 0)) {
    throw new RangeError('\'length\' is out of bounds')
  }

  if (byteOffset === undefined && length === undefined) {
    array = new Uint8Array(array)
  } else if (length === undefined) {
    array = new Uint8Array(array, byteOffset)
  } else {
    array = new Uint8Array(array, byteOffset, length)
  }

  if (Buffer.TYPED_ARRAY_SUPPORT) {
    // Return an augmented `Uint8Array` instance, for best performance
    that = array
    that.__proto__ = Buffer.prototype
  } else {
    // Fallback: Return an object instance of the Buffer class
    that = fromArrayLike(that, array)
  }
  return that
}

function fromObject (that, obj) {
  if (Buffer.isBuffer(obj)) {
    var len = checked(obj.length) | 0
    that = createBuffer(that, len)

    if (that.length === 0) {
      return that
    }

    obj.copy(that, 0, 0, len)
    return that
  }

  if (obj) {
    if ((typeof ArrayBuffer !== 'undefined' &&
        obj.buffer instanceof ArrayBuffer) || 'length' in obj) {
      if (typeof obj.length !== 'number' || isnan(obj.length)) {
        return createBuffer(that, 0)
      }
      return fromArrayLike(that, obj)
    }

    if (obj.type === 'Buffer' && isArray(obj.data)) {
      return fromArrayLike(that, obj.data)
    }
  }

  throw new TypeError('First argument must be a string, Buffer, ArrayBuffer, Array, or array-like object.')
}

function checked (length) {
  // Note: cannot use `length < kMaxLength()` here because that fails when
  // length is NaN (which is otherwise coerced to zero.)
  if (length >= kMaxLength()) {
    throw new RangeError('Attempt to allocate Buffer larger than maximum ' +
                         'size: 0x' + kMaxLength().toString(16) + ' bytes')
  }
  return length | 0
}

function SlowBuffer (length) {
  if (+length != length) { // eslint-disable-line eqeqeq
    length = 0
  }
  return Buffer.alloc(+length)
}

Buffer.isBuffer = function isBuffer (b) {
  return !!(b != null && b._isBuffer)
}

Buffer.compare = function compare (a, b) {
  if (!Buffer.isBuffer(a) || !Buffer.isBuffer(b)) {
    throw new TypeError('Arguments must be Buffers')
  }

  if (a === b) return 0

  var x = a.length
  var y = b.length

  for (var i = 0, len = Math.min(x, y); i < len; ++i) {
    if (a[i] !== b[i]) {
      x = a[i]
      y = b[i]
      break
    }
  }

  if (x < y) return -1
  if (y < x) return 1
  return 0
}

Buffer.isEncoding = function isEncoding (encoding) {
  switch (String(encoding).toLowerCase()) {
    case 'hex':
    case 'utf8':
    case 'utf-8':
    case 'ascii':
    case 'latin1':
    case 'binary':
    case 'base64':
    case 'ucs2':
    case 'ucs-2':
    case 'utf16le':
    case 'utf-16le':
      return true
    default:
      return false
  }
}

Buffer.concat = function concat (list, length) {
  if (!isArray(list)) {
    throw new TypeError('"list" argument must be an Array of Buffers')
  }

  if (list.length === 0) {
    return Buffer.alloc(0)
  }

  var i
  if (length === undefined) {
    length = 0
    for (i = 0; i < list.length; ++i) {
      length += list[i].length
    }
  }

  var buffer = Buffer.allocUnsafe(length)
  var pos = 0
  for (i = 0; i < list.length; ++i) {
    var buf = list[i]
    if (!Buffer.isBuffer(buf)) {
      throw new TypeError('"list" argument must be an Array of Buffers')
    }
    buf.copy(buffer, pos)
    pos += buf.length
  }
  return buffer
}

function byteLength (string, encoding) {
  if (Buffer.isBuffer(string)) {
    return string.length
  }
  if (typeof ArrayBuffer !== 'undefined' && typeof ArrayBuffer.isView === 'function' &&
      (ArrayBuffer.isView(string) || string instanceof ArrayBuffer)) {
    return string.byteLength
  }
  if (typeof string !== 'string') {
    string = '' + string
  }

  var len = string.length
  if (len === 0) return 0

  // Use a for loop to avoid recursion
  var loweredCase = false
  for (;;) {
    switch (encoding) {
      case 'ascii':
      case 'latin1':
      case 'binary':
        return len
      case 'utf8':
      case 'utf-8':
      case undefined:
        return utf8ToBytes(string).length
      case 'ucs2':
      case 'ucs-2':
      case 'utf16le':
      case 'utf-16le':
        return len * 2
      case 'hex':
        return len >>> 1
      case 'base64':
        return base64ToBytes(string).length
      default:
        if (loweredCase) return utf8ToBytes(string).length // assume utf8
        encoding = ('' + encoding).toLowerCase()
        loweredCase = true
    }
  }
}
Buffer.byteLength = byteLength

function slowToString (encoding, start, end) {
  var loweredCase = false

  // No need to verify that "this.length <= MAX_UINT32" since it's a read-only
  // property of a typed array.

  // This behaves neither like String nor Uint8Array in that we set start/end
  // to their upper/lower bounds if the value passed is out of range.
  // undefined is handled specially as per ECMA-262 6th Edition,
  // Section 13.3.3.7 Runtime Semantics: KeyedBindingInitialization.
  if (start === undefined || start < 0) {
    start = 0
  }
  // Return early if start > this.length. Done here to prevent potential uint32
  // coercion fail below.
  if (start > this.length) {
    return ''
  }

  if (end === undefined || end > this.length) {
    end = this.length
  }

  if (end <= 0) {
    return ''
  }

  // Force coersion to uint32. This will also coerce falsey/NaN values to 0.
  end >>>= 0
  start >>>= 0

  if (end <= start) {
    return ''
  }

  if (!encoding) encoding = 'utf8'

  while (true) {
    switch (encoding) {
      case 'hex':
        return hexSlice(this, start, end)

      case 'utf8':
      case 'utf-8':
        return utf8Slice(this, start, end)

      case 'ascii':
        return asciiSlice(this, start, end)

      case 'latin1':
      case 'binary':
        return latin1Slice(this, start, end)

      case 'base64':
        return base64Slice(this, start, end)

      case 'ucs2':
      case 'ucs-2':
      case 'utf16le':
      case 'utf-16le':
        return utf16leSlice(this, start, end)

      default:
        if (loweredCase) throw new TypeError('Unknown encoding: ' + encoding)
        encoding = (encoding + '').toLowerCase()
        loweredCase = true
    }
  }
}

// The property is used by `Buffer.isBuffer` and `is-buffer` (in Safari 5-7) to detect
// Buffer instances.
Buffer.prototype._isBuffer = true

function swap (b, n, m) {
  var i = b[n]
  b[n] = b[m]
  b[m] = i
}

Buffer.prototype.swap16 = function swap16 () {
  var len = this.length
  if (len % 2 !== 0) {
    throw new RangeError('Buffer size must be a multiple of 16-bits')
  }
  for (var i = 0; i < len; i += 2) {
    swap(this, i, i + 1)
  }
  return this
}

Buffer.prototype.swap32 = function swap32 () {
  var len = this.length
  if (len % 4 !== 0) {
    throw new RangeError('Buffer size must be a multiple of 32-bits')
  }
  for (var i = 0; i < len; i += 4) {
    swap(this, i, i + 3)
    swap(this, i + 1, i + 2)
  }
  return this
}

Buffer.prototype.swap64 = function swap64 () {
  var len = this.length
  if (len % 8 !== 0) {
    throw new RangeError('Buffer size must be a multiple of 64-bits')
  }
  for (var i = 0; i < len; i += 8) {
    swap(this, i, i + 7)
    swap(this, i + 1, i + 6)
    swap(this, i + 2, i + 5)
    swap(this, i + 3, i + 4)
  }
  return this
}

Buffer.prototype.toString = function toString () {
  var length = this.length | 0
  if (length === 0) return ''
  if (arguments.length === 0) return utf8Slice(this, 0, length)
  return slowToString.apply(this, arguments)
}

Buffer.prototype.equals = function equals (b) {
  if (!Buffer.isBuffer(b)) throw new TypeError('Argument must be a Buffer')
  if (this === b) return true
  return Buffer.compare(this, b) === 0
}

Buffer.prototype.inspect = function inspect () {
  var str = ''
  var max = exports.INSPECT_MAX_BYTES
  if (this.length > 0) {
    str = this.toString('hex', 0, max).match(/.{2}/g).join(' ')
    if (this.length > max) str += ' ... '
  }
  return '<Buffer ' + str + '>'
}

Buffer.prototype.compare = function compare (target, start, end, thisStart, thisEnd) {
  if (!Buffer.isBuffer(target)) {
    throw new TypeError('Argument must be a Buffer')
  }

  if (start === undefined) {
    start = 0
  }
  if (end === undefined) {
    end = target ? target.length : 0
  }
  if (thisStart === undefined) {
    thisStart = 0
  }
  if (thisEnd === undefined) {
    thisEnd = this.length
  }

  if (start < 0 || end > target.length || thisStart < 0 || thisEnd > this.length) {
    throw new RangeError('out of range index')
  }

  if (thisStart >= thisEnd && start >= end) {
    return 0
  }
  if (thisStart >= thisEnd) {
    return -1
  }
  if (start >= end) {
    return 1
  }

  start >>>= 0
  end >>>= 0
  thisStart >>>= 0
  thisEnd >>>= 0

  if (this === target) return 0

  var x = thisEnd - thisStart
  var y = end - start
  var len = Math.min(x, y)

  var thisCopy = this.slice(thisStart, thisEnd)
  var targetCopy = target.slice(start, end)

  for (var i = 0; i < len; ++i) {
    if (thisCopy[i] !== targetCopy[i]) {
      x = thisCopy[i]
      y = targetCopy[i]
      break
    }
  }

  if (x < y) return -1
  if (y < x) return 1
  return 0
}

// Finds either the first index of `val` in `buffer` at offset >= `byteOffset`,
// OR the last index of `val` in `buffer` at offset <= `byteOffset`.
//
// Arguments:
// - buffer - a Buffer to search
// - val - a string, Buffer, or number
// - byteOffset - an index into `buffer`; will be clamped to an int32
// - encoding - an optional encoding, relevant is val is a string
// - dir - true for indexOf, false for lastIndexOf
function bidirectionalIndexOf (buffer, val, byteOffset, encoding, dir) {
  // Empty buffer means no match
  if (buffer.length === 0) return -1

  // Normalize byteOffset
  if (typeof byteOffset === 'string') {
    encoding = byteOffset
    byteOffset = 0
  } else if (byteOffset > 0x7fffffff) {
    byteOffset = 0x7fffffff
  } else if (byteOffset < -0x80000000) {
    byteOffset = -0x80000000
  }
  byteOffset = +byteOffset  // Coerce to Number.
  if (isNaN(byteOffset)) {
    // byteOffset: it it's undefined, null, NaN, "foo", etc, search whole buffer
    byteOffset = dir ? 0 : (buffer.length - 1)
  }

  // Normalize byteOffset: negative offsets start from the end of the buffer
  if (byteOffset < 0) byteOffset = buffer.length + byteOffset
  if (byteOffset >= buffer.length) {
    if (dir) return -1
    else byteOffset = buffer.length - 1
  } else if (byteOffset < 0) {
    if (dir) byteOffset = 0
    else return -1
  }

  // Normalize val
  if (typeof val === 'string') {
    val = Buffer.from(val, encoding)
  }

  // Finally, search either indexOf (if dir is true) or lastIndexOf
  if (Buffer.isBuffer(val)) {
    // Special case: looking for empty string/buffer always fails
    if (val.length === 0) {
      return -1
    }
    return arrayIndexOf(buffer, val, byteOffset, encoding, dir)
  } else if (typeof val === 'number') {
    val = val & 0xFF // Search for a byte value [0-255]
    if (Buffer.TYPED_ARRAY_SUPPORT &&
        typeof Uint8Array.prototype.indexOf === 'function') {
      if (dir) {
        return Uint8Array.prototype.indexOf.call(buffer, val, byteOffset)
      } else {
        return Uint8Array.prototype.lastIndexOf.call(buffer, val, byteOffset)
      }
    }
    return arrayIndexOf(buffer, [ val ], byteOffset, encoding, dir)
  }

  throw new TypeError('val must be string, number or Buffer')
}

function arrayIndexOf (arr, val, byteOffset, encoding, dir) {
  var indexSize = 1
  var arrLength = arr.length
  var valLength = val.length

  if (encoding !== undefined) {
    encoding = String(encoding).toLowerCase()
    if (encoding === 'ucs2' || encoding === 'ucs-2' ||
        encoding === 'utf16le' || encoding === 'utf-16le') {
      if (arr.length < 2 || val.length < 2) {
        return -1
      }
      indexSize = 2
      arrLength /= 2
      valLength /= 2
      byteOffset /= 2
    }
  }

  function read (buf, i) {
    if (indexSize === 1) {
      return buf[i]
    } else {
      return buf.readUInt16BE(i * indexSize)
    }
  }

  var i
  if (dir) {
    var foundIndex = -1
    for (i = byteOffset; i < arrLength; i++) {
      if (read(arr, i) === read(val, foundIndex === -1 ? 0 : i - foundIndex)) {
        if (foundIndex === -1) foundIndex = i
        if (i - foundIndex + 1 === valLength) return foundIndex * indexSize
      } else {
        if (foundIndex !== -1) i -= i - foundIndex
        foundIndex = -1
      }
    }
  } else {
    if (byteOffset + valLength > arrLength) byteOffset = arrLength - valLength
    for (i = byteOffset; i >= 0; i--) {
      var found = true
      for (var j = 0; j < valLength; j++) {
        if (read(arr, i + j) !== read(val, j)) {
          found = false
          break
        }
      }
      if (found) return i
    }
  }

  return -1
}

Buffer.prototype.includes = function includes (val, byteOffset, encoding) {
  return this.indexOf(val, byteOffset, encoding) !== -1
}

Buffer.prototype.indexOf = function indexOf (val, byteOffset, encoding) {
  return bidirectionalIndexOf(this, val, byteOffset, encoding, true)
}

Buffer.prototype.lastIndexOf = function lastIndexOf (val, byteOffset, encoding) {
  return bidirectionalIndexOf(this, val, byteOffset, encoding, false)
}

function hexWrite (buf, string, offset, length) {
  offset = Number(offset) || 0
  var remaining = buf.length - offset
  if (!length) {
    length = remaining
  } else {
    length = Number(length)
    if (length > remaining) {
      length = remaining
    }
  }

  // must be an even number of digits
  var strLen = string.length
  if (strLen % 2 !== 0) throw new TypeError('Invalid hex string')

  if (length > strLen / 2) {
    length = strLen / 2
  }
  for (var i = 0; i < length; ++i) {
    var parsed = parseInt(string.substr(i * 2, 2), 16)
    if (isNaN(parsed)) return i
    buf[offset + i] = parsed
  }
  return i
}

function utf8Write (buf, string, offset, length) {
  return blitBuffer(utf8ToBytes(string, buf.length - offset), buf, offset, length)
}

function asciiWrite (buf, string, offset, length) {
  return blitBuffer(asciiToBytes(string), buf, offset, length)
}

function latin1Write (buf, string, offset, length) {
  return asciiWrite(buf, string, offset, length)
}

function base64Write (buf, string, offset, length) {
  return blitBuffer(base64ToBytes(string), buf, offset, length)
}

function ucs2Write (buf, string, offset, length) {
  return blitBuffer(utf16leToBytes(string, buf.length - offset), buf, offset, length)
}

Buffer.prototype.write = function write (string, offset, length, encoding) {
  // Buffer#write(string)
  if (offset === undefined) {
    encoding = 'utf8'
    length = this.length
    offset = 0
  // Buffer#write(string, encoding)
  } else if (length === undefined && typeof offset === 'string') {
    encoding = offset
    length = this.length
    offset = 0
  // Buffer#write(string, offset[, length][, encoding])
  } else if (isFinite(offset)) {
    offset = offset | 0
    if (isFinite(length)) {
      length = length | 0
      if (encoding === undefined) encoding = 'utf8'
    } else {
      encoding = length
      length = undefined
    }
  // legacy write(string, encoding, offset, length) - remove in v0.13
  } else {
    throw new Error(
      'Buffer.write(string, encoding, offset[, length]) is no longer supported'
    )
  }

  var remaining = this.length - offset
  if (length === undefined || length > remaining) length = remaining

  if ((string.length > 0 && (length < 0 || offset < 0)) || offset > this.length) {
    throw new RangeError('Attempt to write outside buffer bounds')
  }

  if (!encoding) encoding = 'utf8'

  var loweredCase = false
  for (;;) {
    switch (encoding) {
      case 'hex':
        return hexWrite(this, string, offset, length)

      case 'utf8':
      case 'utf-8':
        return utf8Write(this, string, offset, length)

      case 'ascii':
        return asciiWrite(this, string, offset, length)

      case 'latin1':
      case 'binary':
        return latin1Write(this, string, offset, length)

      case 'base64':
        // Warning: maxLength not taken into account in base64Write
        return base64Write(this, string, offset, length)

      case 'ucs2':
      case 'ucs-2':
      case 'utf16le':
      case 'utf-16le':
        return ucs2Write(this, string, offset, length)

      default:
        if (loweredCase) throw new TypeError('Unknown encoding: ' + encoding)
        encoding = ('' + encoding).toLowerCase()
        loweredCase = true
    }
  }
}

Buffer.prototype.toJSON = function toJSON () {
  return {
    type: 'Buffer',
    data: Array.prototype.slice.call(this._arr || this, 0)
  }
}

function base64Slice (buf, start, end) {
  if (start === 0 && end === buf.length) {
    return base64.fromByteArray(buf)
  } else {
    return base64.fromByteArray(buf.slice(start, end))
  }
}

function utf8Slice (buf, start, end) {
  end = Math.min(buf.length, end)
  var res = []

  var i = start
  while (i < end) {
    var firstByte = buf[i]
    var codePoint = null
    var bytesPerSequence = (firstByte > 0xEF) ? 4
      : (firstByte > 0xDF) ? 3
      : (firstByte > 0xBF) ? 2
      : 1

    if (i + bytesPerSequence <= end) {
      var secondByte, thirdByte, fourthByte, tempCodePoint

      switch (bytesPerSequence) {
        case 1:
          if (firstByte < 0x80) {
            codePoint = firstByte
          }
          break
        case 2:
          secondByte = buf[i + 1]
          if ((secondByte & 0xC0) === 0x80) {
            tempCodePoint = (firstByte & 0x1F) << 0x6 | (secondByte & 0x3F)
            if (tempCodePoint > 0x7F) {
              codePoint = tempCodePoint
            }
          }
          break
        case 3:
          secondByte = buf[i + 1]
          thirdByte = buf[i + 2]
          if ((secondByte & 0xC0) === 0x80 && (thirdByte & 0xC0) === 0x80) {
            tempCodePoint = (firstByte & 0xF) << 0xC | (secondByte & 0x3F) << 0x6 | (thirdByte & 0x3F)
            if (tempCodePoint > 0x7FF && (tempCodePoint < 0xD800 || tempCodePoint > 0xDFFF)) {
              codePoint = tempCodePoint
            }
          }
          break
        case 4:
          secondByte = buf[i + 1]
          thirdByte = buf[i + 2]
          fourthByte = buf[i + 3]
          if ((secondByte & 0xC0) === 0x80 && (thirdByte & 0xC0) === 0x80 && (fourthByte & 0xC0) === 0x80) {
            tempCodePoint = (firstByte & 0xF) << 0x12 | (secondByte & 0x3F) << 0xC | (thirdByte & 0x3F) << 0x6 | (fourthByte & 0x3F)
            if (tempCodePoint > 0xFFFF && tempCodePoint < 0x110000) {
              codePoint = tempCodePoint
            }
          }
      }
    }

    if (codePoint === null) {
      // we did not generate a valid codePoint so insert a
      // replacement char (U+FFFD) and advance only 1 byte
      codePoint = 0xFFFD
      bytesPerSequence = 1
    } else if (codePoint > 0xFFFF) {
      // encode to utf16 (surrogate pair dance)
      codePoint -= 0x10000
      res.push(codePoint >>> 10 & 0x3FF | 0xD800)