jQuery.fn.extend({
	attr: function( name, value ) {
		return jQuery.access( this, jQuery.attr, name, value, arguments.length > 1 );
	},

removeAttr: function( name ) {
		return this.each(function() {
			jQuery.removeAttr( this, name );
		});
	},

prop: function( name, value ) {
		return jQuery.access( this, jQuery.prop, name, value, arguments.length > 1 );
	},

removeProp: function( name ) {
		name = jQuery.propFix[ name ] || name;
		return this.each(function() {
			// try/catch handles cases where IE balks (such as removing a property on window)
			try {
				this[ name ] = undefined;
				delete this[ name ];
			} catch( e ) {}
		});
	},

addClass: function( value ) {
		var classes, elem, cur, clazz, j,
			i = 0,
			len = this.length,
			proceed = typeof value === "string" && value;

if ( jQuery.isFunction( value ) ) {
			return this.each(function( j ) {
				jQuery( this ).addClass( value.call( this, j, this.className ) );
			});
		}

if ( proceed ) {
			// The disjunction here is for better compressibility (see removeClass)
			classes = ( value || "" ).match( core_rnotwhite ) || [];

for ( ; i < len; i++ ) {
				elem = this[ i ];
				cur = elem.nodeType === 1 && ( elem.className ?
					( " " + elem.className + " " ).replace( rclass, " " ) :
					" "
				);

if ( cur ) {
					j = 0;
					while ( (clazz = classes[j++]) ) {
						if ( cur.indexOf( " " + clazz + " " ) < 0 ) {
							cur += clazz + " ";
						}
					}
					elem.className = jQuery.trim( cur );

}
			}
		}

return this;
	},

removeClass: function( value ) {
		var classes, elem, cur, clazz, j,
			i = 0,
			len = this.length,
			proceed = arguments.length === 0 || typeof value === "string" && value;

if ( jQuery.isFunction( value ) ) {
			return this.each(function( j ) {
				jQuery( this ).removeClass( value.call( this, j, this.className ) );
			});
		}
		if ( proceed ) {
			classes = ( value || "" ).match( core_rnotwhite ) || [];

for ( ; i < len; i++ ) {
				elem = this[ i ];
				// This expression is here for better compressibility (see addClass)
				cur = elem.nodeType === 1 && ( elem.className ?
					( " " + elem.className + " " ).replace( rclass, " " ) :
					""
				);

if ( cur ) {
					j = 0;
					while ( (clazz = classes[j++]) ) {
						// Remove *all* instances
						while ( cur.indexOf( " " + clazz + " " ) >= 0 ) {
							cur = cur.replace( " " + clazz + " ", " " );
						}
					}
					elem.className = value ? jQuery.trim( cur ) : "";
				}
			}
		}

return this;
	},

toggleClass: function( value, stateVal ) {
		var type = typeof value,
			isBool = typeof stateVal === "boolean";

if ( jQuery.isFunction( value ) ) {
			return this.each(function( i ) {
				jQuery( this ).toggleClass( value.call(this, i, this.className, stateVal), stateVal );
			});
		}

return this.each(function() {
			if ( type === "string" ) {
				// toggle individual class names
				var className,
					i = 0,
					self = jQuery( this ),
					state = stateVal,
					classNames = value.match( core_rnotwhite ) || [];

while ( (className = classNames[ i++ ]) ) {
					// check each className given, space separated list
					state = isBool ? state : !self.hasClass( className );
					self[ state ? "addClass" : "removeClass" ]( className );
				}

// Toggle whole class name
			} else if ( type === core_strundefined || type === "boolean" ) {
				if ( this.className ) {
					// store className if set
					jQuery._data( this, "__className__", this.className );
				}

// If the element has a class name or if we're passed "false",
				// then remove the whole classname (if there was one, the above saved it).
				// Otherwise bring back whatever was previously saved (if anything),
				// falling back to the empty string if nothing was stored.
				this.className = this.className || value === false ? "" : jQuery._data( this, "__className__" ) || "";
			}
		});
	},

hasClass: function( selector ) {
		var className = " " + selector + " ",
			i = 0,
			l = this.length;
		for ( ; i < l; i++ ) {
			if ( this[i].nodeType === 1 && (" " + this[i].className + " ").replace(rclass, " ").indexOf( className ) >= 0 ) {
				return true;
			}
		}

return false;
	},

val: function( value ) {
		var hooks, ret, isFunction,
			elem = this[0];

if ( !arguments.length ) {
			if ( elem ) {
				hooks = jQuery.valHooks[ elem.type ] || jQuery.valHooks[ elem.nodeName.toLowerCase() ];

if ( hooks && "get" in hooks && (ret = hooks.get( elem, "value" )) !== undefined ) {
					return ret;
				}

ret = elem.value;

return typeof ret === "string" ?
					// handle most common string cases
					ret.replace(rreturn, "") :
					// handle cases where value is null/undef or number
					ret == null ? "" : ret;
			}

return;
		}

isFunction = jQuery.isFunction( value );

return this.each(function( i ) {
			var val,
				self = jQuery(this);

if ( this.nodeType !== 1 ) {
				return;
			}

if ( isFunction ) {
				val = value.call( this, i, self.val() );
			} else {
				val = value;
			}

// Treat null/undefined as ""; convert numbers to string
			if ( val == null ) {
				val = "";
			} else if ( typeof val === "number" ) {
				val += "";
			} else if ( jQuery.isArray( val ) ) {
				val = jQuery.map(val, function ( value ) {
					return value == null ? "" : value + "";
				});
			}

hooks = jQuery.valHooks[ this.type ] || jQuery.valHooks[ this.nodeName.toLowerCase() ];

// If set returns undefined, fall back to normal setting
			if ( !hooks || !("set" in hooks) || hooks.set( this, val, "value" ) === undefined ) {
				this.value = val;
			}
		});
	}
});

jQuery.extend({
	valHooks: {
		option: {
			get: function( elem ) {
				// attributes.value is undefined in Blackberry 4.7 but
				// uses .value. See #6932
				var val = elem.attributes.value;
				return !val || val.specified ? elem.value : elem.text;
			}
		},
		select: {
			get: function( elem ) {
				var value, option,
					options = elem.options,
					index = elem.selectedIndex,
					one = elem.type === "select-one" || index < 0,
					values = one ? null : [],
					max = one ? index + 1 : options.length,
					i = index < 0 ?
						max :
						one ? index : 0;

// Loop through all the selected options
				for ( ; i < max; i++ ) {
					option = options[ i ];

// oldIE doesn't update selected after form reset (#2551)
					if ( ( option.selected || i === index ) &&
							// Don't return options that are disabled or in a disabled optgroup
							( jQuery.support.optDisabled ? !option.disabled : option.getAttribute("disabled") === null ) &&
							( !option.parentNode.disabled || !jQuery.nodeName( option.parentNode, "optgroup" ) ) ) {

// Get the specific value for the option
						value = jQuery( option ).val();

// We don't need an array for one selects
						if ( one ) {
							return value;
						}

// Multi-Selects return an array
						values.push( value );
					}
				}

return values;
			},

set: function( elem, value ) {
				var optionSet, option,
					options = elem.options,
					values = jQuery.makeArray( value ),
					i = options.length;
				
				while ( i-- ) {
					option = options[ i ];
					if ( (option.selected = jQuery.inArray( jQuery(option).val(), values ) >= 0) ) {
						optionSet = true;
					}
				}
				
				// force browsers to behave consistently when non-matching value is set
				if ( !optionSet ) {
					elem.selectedIndex = -1;
				}
				return values;
			}
		}
	},

attr: function( elem, name, value ) {
		var ret, hooks, notxml,
			nType = elem.nodeType;

// don't get/set attributes on text, comment and attribute nodes
		if ( !elem || nType === 3 || nType === 8 || nType === 2 ) {
			return;
		}

// Fallback to prop when attributes are not supported
		if ( typeof elem.getAttribute === core_strundefined ) {
			return jQuery.prop( elem, name, value );
		}

notxml = nType !== 1 || !jQuery.isXMLDoc( elem );

// All attributes are lowercase
		// Grab necessary hook if one is defined
		if ( notxml ) {
			name = name.toLowerCase();
			hooks = jQuery.attrHooks[ name ] || ( rboolean.test( name ) ? boolHook : nodeHook );
		}

if ( value !== undefined ) {

if ( value === null ) {
				jQuery.removeAttr( elem, name );

} else if ( hooks && notxml && "set" in hooks && (ret = hooks.set( elem, value, name )) !== undefined ) {
				return ret;

} else {
				elem.setAttribute( name, value + "" );
				return value;
			}

} else if ( hooks && notxml && "get" in hooks && (ret = hooks.get( elem, name )) !== null ) {
			return ret;

} else {

// In IE9+, Flash objects don't have .getAttribute (#12945)
			// Support: IE9+
			if ( typeof elem.getAttribute !== core_strundefined ) {
				ret =  elem.getAttribute( name );
			}

// Non-existent attributes return null, we normalize to undefined
			return ret == null ?
				undefined :
				ret;
		}
	},

removeAttr: function( elem, value ) {
		var name, propName,
			i = 0,
			attrNames = value && value.match( core_rnotwhite );

if ( attrNames && elem.nodeType === 1 ) {
			while ( (name = attrNames[i++]) ) {
				propName = jQuery.propFix[ name ] || name;

// Boolean attributes get special treatment (#10870)
				// Set corresponding property to false for boolean attributes
				if ( rboolean.test( name ) ) {
					elem[ propName ] = false;
				}

elem.removeAttribute( name );
			}
		}
	},

attrHooks: {
		type: {
			set: function( elem, value ) {
				if ( !jQuery.support.radioValue && value === "radio" && jQuery.nodeName(elem, "input") ) {
					// Setting the type on a radio button after the value resets the value in IE6-9
					// Reset value to default in case type is set after value during creation
					var val = elem.value;
					elem.setAttribute( "type", value );
					if ( val ) {
						elem.value = val;
					}
					return value;
				}
			}
		}
	},

propFix: {
		tabindex: "tabIndex",
		readonly: "readOnly",
		"for": "htmlFor",
		"class": "className",
		maxlength: "maxLength",
		cellspacing: "cellSpacing",
		cellpadding: "cellPadding",
		rowspan: "rowSpan",
		colspan: "colSpan",
		usemap: "useMap",
		frameborder: "frameBorder",
		contenteditable: "contentEditable"
	},

prop: function( elem, name, value ) {
		var ret, hooks, notxml,
			nType = elem.nodeType;

// don't get/set properties on text, comment and attribute nodes
		if ( !elem || nType === 3 || nType === 8 || nType === 2 ) {
			return;
		}

notxml = nType !== 1 || !jQuery.isXMLDoc( elem );

if ( notxml ) {
			// Fix name and attach hooks
			name = jQuery.propFix[ name ] || name;
			hooks = jQuery.propHooks[ name ];
		}

if ( value !== undefined ) {
			if ( hooks && "set" in hooks && (ret = hooks.set( elem, value, name )) !== undefined ) {
				return ret;

} else {
				return ( elem[ name ] = value );
			}

} else {
			if ( hooks && "get" in hooks && (ret = hooks.get( elem, name )) !== null ) {
				return ret;

} else {
				return elem[ name ];
			}
		}
	},

propHooks: {
		tabIndex: {
			get: function( elem ) {
				// elem.tabIndex doesn't always return the correct value when it hasn't been explicitly set
				// http://fluidproject.org/blog/2008/01/09/getting-setting-and-removing-tabindex-values-with-javascript/
				var attributeNode = elem.getAttributeNode("tabindex");

return attributeNode && attributeNode.specified ?
					parseInt( attributeNode.value, 10 ) :
					rfocusable.test( elem.nodeName ) || rclickable.test( elem.nodeName ) && elem.href ?
						0 :
						undefined;
			}
		}
	}
});

// Hook for boolean attributes
boolHook = {
	get: function( elem, name ) {
		return elem.getAttribute( name ) !== null ?
			name.toLowerCase() :
			undefined;
	},
	set: function( elem, value, name ) {
		if ( value === false ) {
			// Remove boolean attributes when set to false
			jQuery.removeAttr( elem, name );
		} else {
			elem.setAttribute( name, name );
		}
		return name;
	}
};

// Radios and checkboxes getter/setter
if ( !jQuery.support.checkOn ) {
	jQuery.each([ "radio", "checkbox" ], function() {
		jQuery.valHooks[ this ] = {
			get: function( elem ) {
				// Handle the case where in Webkit "" is returned instead of "on" if a value isn't specified
				return elem.getAttribute("value") === null ? "on" : elem.value;
			}
		};
	});
}
jQuery.each([ "radio", "checkbox" ], function() {
	jQuery.valHooks[ this ] = jQuery.extend( jQuery.valHooks[ this ], {
		set: function( elem, value ) {
			if ( jQuery.isArray( value ) ) {
				return ( elem.checked = jQuery.inArray( jQuery(elem).val(), value ) >= 0 );
			}
		}
	});
});

// IE9/10 do not see a selected option inside an optgroup unless you access it
// Support: IE9, IE10
if ( !jQuery.support.optSelected ) {
	jQuery.propHooks.selected = jQuery.extend( jQuery.propHooks.selected, {
		get: function( elem ) {
			var parent = elem.parentNode;
			if ( parent && parent.parentNode ) {
				parent.parentNode.selectedIndex;
			}
			return null;
		}
	});
}

src/attributes.js

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