this

Consider the following code: function A() {} A.prototype.go = function() { console.log(this); //A { go=function()} var f = function() { console.log(this); //Window }; f(); } var a = new A(); a.go(); Why does 'this' inside function 'f' refers to the global scope? Why it is not the scope of function 'A' ? JavaScript has a different concept of what the special name this refers to than most other programming languages do. There are exactly five different ways in which the value of this can be bound in the language. The Global Scope this; When using this in global scope, it will simply refer to the

what about using "this" with methods in Java? Is it optional or there are situations when one needs to use it obligatory? The only situation I have encountered is when in the class you invoke a method within a method. But it is optional. Here is a silly example just to show what I mean: public class Test { String s; private String hey() { return s; } public String getS(){ String sm = this.hey(); // here I could just write hey(); without this return sm; } } Three obvious situations where you need it: Calling another constructor in the same class as the first part of your constructor

We have this line in my code base: var uncurryThis = Function.bind.bind(Function.call); That I'm trying to work through. Presumably, it uncurries. How do I work this out? I guess it's a version of Function.bind whose own this is bound to Function.call . Doesn't help me enough. And I haven't found any uses, so I'm not even sure if you call it standalone or need to call it "as a method", only, you know, bind it first. It passes the call function to the bind function, with the bind function itself being the value of this . Thus you get in return a wrapper around the bind function that arranges

I have this method that I want to use $this in but all I get is: Fatal error: Using $this when not in object context. How can I get this to work? public static function userNameAvailibility() { $result = $this->getsomthin(); } This is the correct way public static function userNameAvailibility() { $result = self::getsomthin(); } Use self:: instead of $this-> for static methods . See: PHP Static Methods Tutorial for more info :) You can't use $this inside a static function, because static functions are independent of any instantiated object. Try making the function not static. Edit : By