I'm using protypal inheritance and I would like to call an overridden method on the base class. In PHP I could do this using parent::functionName. Is this possible using JavaScript protypal inheritance?
Consider the following example:
var A = function(){
this.doSomething = function(){
console.log('doSomething in A');
};
};
var B = function() {
this.doSomething = function(){
//I would like to call A.doSomething()
//I tried this.prototype.doSomething() and A.doSomething.call(this), but neither works
console.log('doSomething in B');
};
};
B.prototype = new A();
var test = new B();
test.doSomething();
The output that I'm looking for in the console is:
doSomething in B
doSomething in A
With the code defined as I have it in the following fiddle: http://jsfiddle.net/JAAulde/psdym/2/
The best way is to .call() or .apply() A's method inside of B's:
//Inside of B.doSomething
A.prototype.doSomething.call( this, arg1, arg2 );
Or, to simply pass all params that came into B.doSomething() in one fell swoop
//Inside of B.doSomething
A.prototype.doSomething.apply( this, arguments );
An amazing book (written by a friend of mine) for learning about various patterns for inheritance in JS is http://www.amazon.com/JavaScript-Design-Patterns-Recipes-Problem-Solution/dp/159059908X
from my own best practices, best to create
var parent = ...;
when creating the object if reference to the parent is actually needed - which is not as much as one would expect. then use as desired.
I personally think the term "objects" is misleading in reference to javascript since
object == function == closure
essentially giving the tools for an objectness without limiting to formal object / inheritance constraints. on the up side it makes a very fluid, mutable language; on the downside, you need to fill in yourself missing pieces when needed.
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