_.bindKey

_.bindKey(object, key, [partials])

Creates a function that invokes the method at object[key] with partials prepended to the arguments it receives.

This method differs from _.bind by allowing bound functions to reference methods that may be redefined or don't yet exist. See Peter Michaux's article for more details.

The _.bindKey.placeholder value, which defaults to _ in monolithic builds, may be used as a placeholder for partially applied arguments.

Since

0.10.0

Arguments

1. object (Object): The object to invoke the method on.
2. key (string): The key of the method.
3. [partials] (...*): The arguments to be partially applied.

Returns

(Function): Returns the new bound function.

Example

var object = {
  'user': 'fred',

  'greet': function(greeting, punctuation) {
    return greeting + ' ' + this.user + punctuation;
  }
};
 

var bound = _.bindKey(object, 'greet', 'hi');

bound('!');
// => 'hi fred!'
 
object.greet = function(greeting, punctuation) {
  return greeting + 'ya ' + this.user + punctuation;
};
 

bound('!');
// => 'hiya fred!'
 
// Bound with placeholders.

var bound = _.bindKey(object, 'greet', _, '!');

bound('hi');
// => 'hiya fred!'