Object.prototype.__lookupSetter__()

The __lookupSetter__ method returns the function bound as a setter to the specified property.

Syntax

obj.__lookupSetter__(sprop)

Parameters

sprop

A string containing the name of the property whose setter should be returned.

Return value

The function bound as a setter to the specified property.

Description

If a setter has been defined for an object's property, it was not possible to reference the setter function through that property, because that property refers to the return value of that function. __lookupSetter__ can be used to obtain a reference to the setter function.

It is now possible to do this in a standardized way using Object.getOwnPropertyDescriptor().

Examples

var obj = {
  set foo(value) {
    this.bar = value;
  }
};
// Non-standard and deprecated way
obj.__lookupSetter__('foo')
// (function(value) { this.bar = value; })
// Standard-compliant way
Object.getOwnPropertyDescriptor(obj, 'foo').set;
// (function(value) { this.bar = value; })

Specifications

Browser compatibility

See also

• Object.prototype.__lookupGetter__()
• set operator
• Object.getOwnPropertyDescriptor() and Object.getPrototypeOf()
• Object.prototype.__defineGetter__()
• Object.prototype.__defineSetter__()
• JS Guide: Defining Getters and Setters