Object.prototype.__lookupGetter__()

Los __lookupGetter__ metodos retornan la funcion  enlazada como un getter para especificar la propiedad.

Syntax

obj.__lookupGetter__(sprop)

Parameters

sprop

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

Return value

The function bound as a getter to the specified property.

Description

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

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

Examples

var obj = {
  get foo() {
    return Math.random() > 0.5 ? 'foo' : 'bar';
  }
};


// Non-standard and deprecated way
obj.__lookupGetter__('foo');
// (function() { return Math.random() > 0.5 ? 'foo' : 'bar'; })


// Standard-compliant way
Object.getOwnPropertyDescriptor(obj, "foo").get;
// (function() { return Math.random() > 0.5 ? 'foo' : 'bar'; })

Specifications

Browser compatibility

See also

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