// Initialize a jQuery object

  define( [

  	"../core",

  	"../var/document",

  	"./var/rsingleTag",
  	"../traversing/findFilter"

  ], function( jQuery, document, rsingleTag ) {
  
  "use strict";

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

  	// 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 <)

  	// Shortcut simple #id case for speed
  	rquickExpr = /^(?:\s*(<[\w\W]+>)[^>]*|#([\w-]+))$/,

  	init = jQuery.fn.init = function( selector, context, root ) {

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

  		// Method init() accepts an alternate rootjQuery
  		// so migrate can support jQuery.sub (gh-2101)
  		root = root || rootjQuery;

  		// Handle HTML strings
  		if ( typeof selector === "string" ) {

  			if ( selector[ 0 ] === "<" &&
  				selector[ 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;

  					// Option to run scripts is true for back-compat

  					// Intentionally let the error be thrown if parseHTML is not present
  					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 ] );

  					if ( elem ) {
  
  						// Inject the element directly into the jQuery object
  						this[ 0 ] = elem;

  						this.length = 1;

  					}

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

  				return ( context || root ).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[ 0 ] = selector;

  			this.length = 1;
  			return this;
  
  		// HANDLE: $(function)
  		// Shortcut for document ready
  		} else if ( jQuery.isFunction( selector ) ) {

  			return root.ready !== undefined ?
  				root.ready( selector ) :

  				// Execute immediately if ready is not present
  				selector( jQuery );
  		}

  		return jQuery.makeArray( selector, this );
  	};
  
  // Give the init function the jQuery prototype for later instantiation
  init.prototype = jQuery.fn;
  
  // Initialize central reference
  rootjQuery = jQuery( document );
  
  return init;

  } );