var
	// A central reference to the root jQuery(document)
	rootjQuery,

// The deferred used on DOM ready
	readyList,

// Support: IE9
	// For `typeof xmlNode.method` instead of `xmlNode.method !== undefined`
	core_strundefined = typeof undefined,

// Use the correct document accordingly with window argument (sandbox)
	location = window.location,
	document = window.document,
	docElem = document.documentElement,

// Map over jQuery in case of overwrite
	_jQuery = window.jQuery,

// Map over the $ in case of overwrite
	_$ = window.$,

// [[Class]] -> type pairs
	class2type = {},

// List of deleted data cache ids, so we can reuse them
	core_deletedIds = [],

core_version = "@VERSION",

// Save a reference to some core methods
	core_concat = core_deletedIds.concat,
	core_push = core_deletedIds.push,
	core_slice = core_deletedIds.slice,
	core_indexOf = core_deletedIds.indexOf,
	core_toString = class2type.toString,
	core_hasOwn = class2type.hasOwnProperty,
	core_trim = core_version.trim,

// Define a local copy of jQuery
	jQuery = function( selector, context ) {
		// The jQuery object is actually just the init constructor 'enhanced'
		return new jQuery.fn.init( selector, context, rootjQuery );
	},

// Used for matching numbers
	core_pnum = /[+-]?(?:\d*\.|)\d+(?:[eE][+-]?\d+|)/.source,

// Used for splitting on whitespace
	core_rnotwhite = /\S+/g,

// A simple way to check for HTML strings
	// Prioritize #id over <tag> to avoid XSS via location.hash (#9521)
	// Strict HTML recognition (#11290: must start with <)
	rquickExpr = /^(?:(<[\w\W]+>)[^>]*|#([\w-]*))$/,

// Match a standalone tag
	rsingleTag = /^<(\w+)\s*\/?>(?:<\/\1>|)$/,

// Matches dashed string for camelizing
	rmsPrefix = /^-ms-/,
	rdashAlpha = /-([\da-z])/gi,

// Used by jQuery.camelCase as callback to replace()
	fcamelCase = function( all, letter ) {
		return letter.toUpperCase();
	},

// The ready event handler and self cleanup method
	completed = function() {
		document.removeEventListener( "DOMContentLoaded", completed, false );
		window.removeEventListener( "load", completed, false );
		jQuery.ready();
	};

jQuery.fn = jQuery.prototype = {
	// The current version of jQuery being used
	jquery: core_version,

constructor: jQuery,
	init: function( selector, context, rootjQuery ) {
		var match, elem;

// HANDLE: $(""), $(null), $(undefined), $(false)
		if ( !selector ) {
			return this;
		}

// Handle HTML strings
		if ( typeof selector === "string" ) {
			if ( selector.charAt(0) === "<" && selector.charAt( selector.length - 1 ) === ">" && selector.length >= 3 ) {
				// Assume that strings that start and end with <> are HTML and skip the regex check
				match = [ null, selector, null ];

} else {
				match = rquickExpr.exec( selector );
			}

// Match html or make sure no context is specified for #id
			if ( match && (match[1] || !context) ) {

// HANDLE: $(html) -> $(array)
				if ( match[1] ) {
					context = context instanceof jQuery ? context[0] : context;

// scripts is true for back-compat
					jQuery.merge( this, jQuery.parseHTML(
						match[1],
						context && context.nodeType ? context.ownerDocument || context : document,
						true
					) );

// HANDLE: $(html, props)
					if ( rsingleTag.test( match[1] ) && jQuery.isPlainObject( context ) ) {
						for ( match in context ) {
							// Properties of context are called as methods if possible
							if ( jQuery.isFunction( this[ match ] ) ) {
								this[ match ]( context[ match ] );

// ...and otherwise set as attributes
							} else {
								this.attr( match, context[ match ] );
							}
						}
					}

return this;

// HANDLE: $(#id)
				} else {
					elem = document.getElementById( match[2] );

// Check parentNode to catch when Blackberry 4.6 returns
					// nodes that are no longer in the document #6963
					if ( elem && elem.parentNode ) {
						// Handle the case where IE and Opera return items
						// by name instead of ID
						if ( elem.id !== match[2] ) {
							return rootjQuery.find( selector );
						}

// Otherwise, we inject the element directly into the jQuery object
						this.length = 1;
						this[0] = elem;
					}

this.context = document;
					this.selector = selector;
					return this;
				}

// HANDLE: $(expr, $(...))
			} else if ( !context || context.jquery ) {
				return ( context || rootjQuery ).find( selector );

// HANDLE: $(expr, context)
			// (which is just equivalent to: $(context).find(expr)
			} else {
				return this.constructor( context ).find( selector );
			}

// HANDLE: $(DOMElement)
		} else if ( selector.nodeType ) {
			this.context = this[0] = selector;
			this.length = 1;
			return this;

// HANDLE: $(function)
		// Shortcut for document ready
		} else if ( jQuery.isFunction( selector ) ) {
			return rootjQuery.ready( selector );
		}

if ( selector.selector !== undefined ) {
			this.selector = selector.selector;
			this.context = selector.context;
		}

return jQuery.makeArray( selector, this );
	},

// Start with an empty selector
	selector: "",

// The default length of a jQuery object is 0
	length: 0,

// The number of elements contained in the matched element set
	size: function() {
		return this.length;
	},

toArray: function() {
		return core_slice.call( this );
	},

// Get the Nth element in the matched element set OR
	// Get the whole matched element set as a clean array
	get: function( num ) {
		return num == null ?

// Return a 'clean' array
			this.toArray() :

// Return just the object
			( num < 0 ? this[ this.length + num ] : this[ num ] );
	},

// Take an array of elements and push it onto the stack
	// (returning the new matched element set)
	pushStack: function( elems ) {

// Build a new jQuery matched element set
		var ret = jQuery.merge( this.constructor(), elems );

// Add the old object onto the stack (as a reference)
		ret.prevObject = this;
		ret.context = this.context;

// Return the newly-formed element set
		return ret;
	},

// Execute a callback for every element in the matched set.
	// (You can seed the arguments with an array of args, but this is
	// only used internally.)
	each: function( callback, args ) {
		return jQuery.each( this, callback, args );
	},

ready: function( fn ) {
		// Add the callback
		jQuery.ready.promise().done( fn );

return this;
	},

slice: function() {
		return this.pushStack( core_slice.apply( this, arguments ) );
	},

first: function() {
		return this.eq( 0 );
	},

last: function() {
		return this.eq( -1 );
	},

eq: function( i ) {
		var len = this.length,
			j = +i + ( i < 0 ? len : 0 );
		return this.pushStack( j >= 0 && j < len ? [ this[j] ] : [] );
	},

map: function( callback ) {
		return this.pushStack( jQuery.map(this, function( elem, i ) {
			return callback.call( elem, i, elem );
		}));
	},

end: function() {
		return this.prevObject || this.constructor(null);
	},

// For internal use only.
	// Behaves like an Array's method, not like a jQuery method.
	push: core_push,
	sort: [].sort,
	splice: [].splice
};

// Give the init function the jQuery prototype for later instantiation
jQuery.fn.init.prototype = jQuery.fn;

jQuery.extend = jQuery.fn.extend = function() {
	var options, name, src, copy, copyIsArray, clone,
		target = arguments[0] || {},
		i = 1,
		length = arguments.length,
		deep = false;

// Handle a deep copy situation
	if ( typeof target === "boolean" ) {
		deep = target;
		target = arguments[1] || {};
		// skip the boolean and the target
		i = 2;
	}

// Handle case when target is a string or something (possible in deep copy)
	if ( typeof target !== "object" && !jQuery.isFunction(target) ) {
		target = {};
	}

// extend jQuery itself if only one argument is passed
	if ( length === i ) {
		target = this;
		--i;
	}

for ( ; i < length; i++ ) {
		// Only deal with non-null/undefined values
		if ( (options = arguments[ i ]) != null ) {
			// Extend the base object
			for ( name in options ) {
				src = target[ name ];
				copy = options[ name ];

// Prevent never-ending loop
				if ( target === copy ) {
					continue;
				}

// Recurse if we're merging plain objects or arrays
				if ( deep && copy && ( jQuery.isPlainObject(copy) || (copyIsArray = jQuery.isArray(copy)) ) ) {
					if ( copyIsArray ) {
						copyIsArray = false;
						clone = src && jQuery.isArray(src) ? src : [];

} else {
						clone = src && jQuery.isPlainObject(src) ? src : {};
					}

// Never move original objects, clone them
					target[ name ] = jQuery.extend( deep, clone, copy );

// Don't bring in undefined values
				} else if ( copy !== undefined ) {
					target[ name ] = copy;
				}
			}
		}
	}

// Return the modified object
	return target;
};

jQuery.extend({
	// Unique for each copy of jQuery on the page
	expando: "jQuery" + ( core_version + Math.random() ).replace( /\D/g, "" ),

noConflict: function( deep ) {
		if ( window.$ === jQuery ) {
			window.$ = _$;
		}

if ( deep && window.jQuery === jQuery ) {
			window.jQuery = _jQuery;
		}

return jQuery;
	},

// Is the DOM ready to be used? Set to true once it occurs.
	isReady: false,

// A counter to track how many items to wait for before
	// the ready event fires. See #6781
	readyWait: 1,

// Hold (or release) the ready event
	holdReady: function( hold ) {
		if ( hold ) {
			jQuery.readyWait++;
		} else {
			jQuery.ready( true );
		}
	},

// Handle when the DOM is ready
	ready: function( wait ) {

// Abort if there are pending holds or we're already ready
		if ( wait === true ? --jQuery.readyWait : jQuery.isReady ) {
			return;
		}

// Remember that the DOM is ready
		jQuery.isReady = true;

// If a normal DOM Ready event fired, decrement, and wait if need be
		if ( wait !== true && --jQuery.readyWait > 0 ) {
			return;
		}

// If there are functions bound, to execute
		readyList.resolveWith( document, [ jQuery ] );

// Trigger any bound ready events
		if ( jQuery.fn.trigger ) {
			jQuery( document ).trigger("ready").off("ready");
		}
	},

// See test/unit/core.js for details concerning isFunction.
	// Since version 1.3, DOM methods and functions like alert
	// aren't supported. They return false on IE (#2968).
	isFunction: function( obj ) {
		return jQuery.type(obj) === "function";
	},

isArray: Array.isArray,

isWindow: function( obj ) {
		return obj != null && obj == obj.window;
	},

isNumeric: function( obj ) {
		return !isNaN( parseFloat(obj) ) && isFinite( obj );
	},

type: function( obj ) {
		if ( obj == null ) {
			return String( obj );
		}
		// Support: Safari <=5.1 (functionish RegExp)
		return typeof obj === "object" || typeof obj === "function" ?
			class2type[ core_toString.call(obj) ] || "object" :
			typeof obj;
	},

isPlainObject: function( obj ) {
		// Not plain objects:
		// - Any object or value whose internal [[Class]] property is not "[object Object]"
		// - DOM nodes
		// - window
		if ( jQuery.type( obj ) !== "object" || obj.nodeType || jQuery.isWindow( obj ) ) {
			return false;
		}

// Support: Firefox >16
		// The try/catch suppresses exceptions thrown when attempting to access
		// the "constructor" property of certain host objects, ie. |window.location|
		try {
			if ( obj.constructor &&
					!core_hasOwn.call( obj.constructor.prototype, "isPrototypeOf" ) ) {
				return false;
			}
		} catch ( e ) {
			return false;
		}

// If the function hasn't returned already, we're confident that
		// |obj| is a plain object, created by {} or constructed with new Object
		return true;
	},

isEmptyObject: function( obj ) {
		var name;
		for ( name in obj ) {
			return false;
		}
		return true;
	},

error: function( msg ) {
		throw new Error( msg );
	},

// data: string of html
	// context (optional): If specified, the fragment will be created in this context, defaults to document
	// keepScripts (optional): If true, will include scripts passed in the html string
	parseHTML: function( data, context, keepScripts ) {
		if ( !data || typeof data !== "string" ) {
			return null;
		}
		if ( typeof context === "boolean" ) {
			keepScripts = context;
			context = false;
		}
		context = context || document;

var parsed = rsingleTag.exec( data ),
			scripts = !keepScripts && [];

// Single tag
		if ( parsed ) {
			return [ context.createElement( parsed[1] ) ];
		}

parsed = jQuery.buildFragment( [ data ], context, scripts );

if ( scripts ) {
			jQuery( scripts ).remove();
		}

return jQuery.merge( [], parsed.childNodes );
	},

parseJSON: JSON.parse,

// Cross-browser xml parsing
	parseXML: function( data ) {
		var xml, tmp;
		if ( !data || typeof data !== "string" ) {
			return null;
		}

// Support: IE9
		try {
			tmp = new DOMParser();
			xml = tmp.parseFromString( data , "text/xml" );
		} catch ( e ) {
			xml = undefined;
		}

if ( !xml || xml.getElementsByTagName( "parsererror" ).length ) {
			jQuery.error( "Invalid XML: " + data );
		}
		return xml;
	},

noop: function() {},

// Evaluates a script in a global context
	globalEval: function( data ) {
		var indirect = eval;
		if ( jQuery.trim( data ) ) {
			indirect( data + ";" );
		}
	},

// Convert dashed to camelCase; used by the css and data modules
	// Microsoft forgot to hump their vendor prefix (#9572)
	camelCase: function( string ) {
		return string.replace( rmsPrefix, "ms-" ).replace( rdashAlpha, fcamelCase );
	},

nodeName: function( elem, name ) {
		return elem.nodeName && elem.nodeName.toLowerCase() === name.toLowerCase();
	},

// args is for internal usage only
	each: function( obj, callback, args ) {
		var value,
			i = 0,
			length = obj.length,
			isArray = isArraylike( obj );

if ( args ) {
			if ( isArray ) {
				for ( ; i < length; i++ ) {
					value = callback.apply( obj[ i ], args );

if ( value === false ) {
						break;
					}
				}
			} else {
				for ( i in obj ) {
					value = callback.apply( obj[ i ], args );

if ( value === false ) {
						break;
					}
				}
			}

// A special, fast, case for the most common use of each
		} else {
			if ( isArray ) {
				for ( ; i < length; i++ ) {
					value = callback.call( obj[ i ], i, obj[ i ] );

if ( value === false ) {
						break;
					}
				}
			} else {
				for ( i in obj ) {
					value = callback.call( obj[ i ], i, obj[ i ] );

if ( value === false ) {
						break;
					}
				}
			}
		}

return obj;
	},

trim: function( text ) {
		return text == null ? "" : core_trim.call( text );
	},

// results is for internal usage only
	makeArray: function( arr, results ) {
		var ret = results || [];

if ( arr != null ) {
			if ( isArraylike( Object(arr) ) ) {
				jQuery.merge( ret,
					typeof arr === "string" ?
					[ arr ] : arr
				);
			} else {
				core_push.call( ret, arr );
			}
		}

return ret;
	},

inArray: function( elem, arr, i ) {
		return arr == null ? -1 : core_indexOf.call( arr, elem, i );
	},

merge: function( first, second ) {
		var l = second.length,
			i = first.length,
			j = 0;

if ( typeof l === "number" ) {
			for ( ; j < l; j++ ) {
				first[ i++ ] = second[ j ];
			}
		} else {
			while ( second[j] !== undefined ) {
				first[ i++ ] = second[ j++ ];
			}
		}

first.length = i;

return first;
	},

grep: function( elems, callback, inv ) {
		var retVal,
			ret = [],
			i = 0,
			length = elems.length;
		inv = !!inv;

// Go through the array, only saving the items
		// that pass the validator function
		for ( ; i < length; i++ ) {
			retVal = !!callback( elems[ i ], i );
			if ( inv !== retVal ) {
				ret.push( elems[ i ] );
			}
		}

return ret;
	},

// arg is for internal usage only
	map: function( elems, callback, arg ) {
		var value,
			i = 0,
			length = elems.length,
			isArray = isArraylike( elems ),
			ret = [];

// Go through the array, translating each of the items to their
		if ( isArray ) {
			for ( ; i < length; i++ ) {
				value = callback( elems[ i ], i, arg );

if ( value != null ) {
					ret[ ret.length ] = value;
				}
			}

// Go through every key on the object,
		} else {
			for ( i in elems ) {
				value = callback( elems[ i ], i, arg );

if ( value != null ) {
					ret[ ret.length ] = value;
				}
			}
		}

// Flatten any nested arrays
		return core_concat.apply( [], ret );
	},

// A global GUID counter for objects
	guid: 1,

// Bind a function to a context, optionally partially applying any
	// arguments.
	proxy: function( fn, context ) {
		var tmp, args, proxy;

if ( typeof context === "string" ) {
			tmp = fn[ context ];
			context = fn;
			fn = tmp;
		}

// Quick check to determine if target is callable, in the spec
		// this throws a TypeError, but we will just return undefined.
		if ( !jQuery.isFunction( fn ) ) {
			return undefined;
		}

// Simulated bind
		args = core_slice.call( arguments, 2 );
		proxy = function() {
			return fn.apply( context || this, args.concat( core_slice.call( arguments ) ) );
		};

// Set the guid of unique handler to the same of original handler, so it can be removed
		proxy.guid = fn.guid = fn.guid || jQuery.guid++;

return proxy;
	},

// Multifunctional method to get and set values of a collection
	// The value/s can optionally be executed if it's a function
	access: function( elems, fn, key, value, chainable, emptyGet, raw ) {
		var i = 0,
			length = elems.length,
			bulk = key == null;

// Sets many values
		if ( jQuery.type( key ) === "object" ) {
			chainable = true;
			for ( i in key ) {
				jQuery.access( elems, fn, i, key[i], true, emptyGet, raw );
			}

// Sets one value
		} else if ( value !== undefined ) {
			chainable = true;

if ( !jQuery.isFunction( value ) ) {
				raw = true;
			}

if ( bulk ) {
				// Bulk operations run against the entire set
				if ( raw ) {
					fn.call( elems, value );
					fn = null;

// ...except when executing function values
				} else {
					bulk = fn;
					fn = function( elem, key, value ) {
						return bulk.call( jQuery( elem ), value );
					};
				}
			}

if ( fn ) {
				for ( ; i < length; i++ ) {
					fn( elems[i], key, raw ? value : value.call( elems[i], i, fn( elems[i], key ) ) );
				}
			}
		}

return chainable ?
			elems :

// Gets
			bulk ?
				fn.call( elems ) :
				length ? fn( elems[0], key ) : emptyGet;
	},

now: Date.now
});

jQuery.ready.promise = function( obj ) {
	if ( !readyList ) {

readyList = jQuery.Deferred();

// Catch cases where $(document).ready() is called after the browser event has already occurred.
		// we once tried to use readyState "interactive" here, but it caused issues like the one
		// discovered by ChrisS here: http://bugs.jquery.com/ticket/12282#comment:15
		if ( document.readyState === "complete" ) {
			// Handle it asynchronously to allow scripts the opportunity to delay ready
			setTimeout( jQuery.ready );

} else {

// Use the handy event callback
			document.addEventListener( "DOMContentLoaded", completed, false );

// A fallback to window.onload, that will always work
			window.addEventListener( "load", completed, false );
		}
	}
	return readyList.promise( obj );
};

// Populate the class2type map
jQuery.each("Boolean Number String Function Array Date RegExp Object Error".split(" "), function(i, name) {
	class2type[ "[object " + name + "]" ] = name.toLowerCase();
});

function isArraylike( obj ) {
	var length = obj.length,
		type = jQuery.type( obj );

if ( jQuery.isWindow( obj ) ) {
		return false;
	}

if ( obj.nodeType === 1 && length ) {
		return true;
	}

return type === "array" || type !== "function" &&
		( length === 0 ||
		typeof length === "number" && length > 0 && ( length - 1 ) in obj );
}

// All jQuery objects should point back to these
rootjQuery = jQuery(document);

src/core.js

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