Object type inquiry enhancments via $.nativeType()

nativeType.jquery.js

(function( jQuery, undefined ){

	var toString = ({}).toString,
		hasOwn = ({}).hasOwnProperty,
		slice = [].slice,
		push = [].push,

		// [[Class]] --> type (for all natives)
		class2type = {},

		// Used to test if an object is a host one - IE6-8 only.
		testSlice = function( obj ) {
			try {
				slice.call( obj, 0, 0 );
				return true;
			} catch (e) {
				return false;
			}
		};

	// If not IE6-8, do not use the slice test!
	if ( testSlice( window ) ) {
		testSlice = 0;
	}

	// First 3 has to be considered objects.
	// (There is no a strong cross-browser way to detect arguments.)
	jQuery.each("Object Arguments Math Boolean Number String Function Array Date RegExp".split(" "), function( i, name ) {
		class2type[ "[object " + name + "]" ] = i < 3 ? "object" : name.toLowerCase();
	});

	// Returns "" for not natives.
	jQuery.nativeType = function( obj ) {
		if ( obj == null ) {
			return "" + obj;
		}

		var type = class2type[ toString.call( obj ) ];

		return !type || testSlice && type === "object" &&
			( !("hasOwnProperty" in obj) || "setInterval" in obj && !testSlice(obj) ) ?
			"" : type;
	};

	jQuery.isWindow = function( obj ) {
		return !jQuery.nativeType( obj ) && "setInterval" in obj;
	};

	jQuery.isPlainObject = function( obj ) {
		if ( !obj || jQuery.nativeType( obj ) !== "object" ||
			// Not own constructor property must be Object.
			obj.constructor &&
			!hasOwn.call(obj, "constructor") &&
			!hasOwn.call(obj.constructor.prototype || {}, "isPrototypeOf") ) {
			return false;
		}

		// All (enumerable) properties should be own (not inherited).
		for ( var name in obj ) {
			if ( !hasOwn.call( obj, name ) ) {
				return false;
			}
		}

		return true;
	};

	jQuery.makeArray = function( obj, ret ) {
		ret = ret || [];

		if ( obj != null ) {
			var native_type = jQuery.nativeType( obj );

			if ( native_type === "array" ) {
				push.apply( ret, obj );

			} else if ( obj.length == null || ( native_type ? native_type !== "object" : "setInterval" in obj ) ) {
				push.call( ret, obj );

			} else {
				jQuery.merge( ret, obj );
			}
		}

		return ret;
	};

	//------------------------------
	// EXAMPLES:

	jQuery.isNode = function( obj ) {
		return !jQuery.nativeType( obj ) && "nodeType" in obj && !( "setInterval" in obj );
	};

	jQuery.xtype = function( obj ) {
		return jQuery.nativeType( obj ) ||
			// Test if window first because it can easily contain other properties too.
			"setInterval" in obj && "window" ||
			"nodeType" in obj && "node" ||
			"item" in obj && "length" in obj && "list" ||
			"";
	};

	jQuery.isjQuery = function( obj ) {
		return typeof obj === "object" && "jquery" in obj && !hasOwn.call( obj, "jquery" );
	};

})( jQuery );