Is there a way to "undefine" an instance method to reveal the method defined in a prototype?

I'm trying to wrap my head around javascript prototypes, and started to wonder if there is a way to remove/undefine an instance method defined on an object, so the method in the prototype would be called. So in the following

/* javascript */
function Foo () {};
Foo.prototype.myMethod = function() {alert('foo')};

var foo1 = new Foo();
var foo2 = new Foo();

foo1.myMethod = function () {alert('foo changed for instance')};
Foo.prototype.myMethod = function () {alert('foo changed in prototype')};

foo1.myMethod(); // alerts 'foo ch开发者_Go百科anged for instance'
foo2.myMethod(); // alerts 'foo changed in prototype'

Is there a way to remove myMethod from instance foo1, so that calling foo1.myMethod(); would call the method defined in the prototype and alert "foo changed in prototype"?

I guess I'm after something akin to removing a method from singleton class in Ruby, like:

# ruby
class Foo
  def myMethod
    puts "foo"
  end
end

f = Foo.new
f.myMethod # => foo

# make singleton class, re-define myMethod for this instance
def f.myMethod
  puts "bar"
end
f.myMethod # => bar

# remove method from singleton class
class << f
  remove_method :myMethod
end
f.myMethod # => foo

I'm asking out of sheer interest, so bonus points for practical use cases for this..

You can do so with delete:

The delete operator deletes a property of an object, or an element at a specified index in an array.

delete foo1['myMethod'];

It is the only way to remove properties of an object. A practical use case would be to remove entries from a hash table, which is implemented by using an object.

You can delete it

function Foo () {};
Foo.prototype.myMethod = function() {alert('foo')};

var foo1 = new Foo();
var foo2 = new Foo();

foo1.myMethod = function () {alert('foo changed for instance')};
Foo.prototype.myMethod = function () {alert('foo changed in prototype')};

foo1.myMethod(); // alerts 'foo changed for instance'
foo2.myMethod(); // alerts 'foo changed in prototype'


// deleting the unwanted method
delete foo1.myMethod;

foo1.myMethod(); // alerts 'foo changed in prototype'
foo2.myMethod(); // alerts 'foo changed in prototype'