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This is an example: function one() { var a = 1; two(); function two() { var b = 2; three(); function three() { var c = 3; alert(a + b + c); // 6 } } } one()​; //calling the function Now when we call function one(), the result is 6 . So it's all about scope chain, all variables are resolved, now I have one question. Why do we need this " this " keyword when all variables are getting resolved through scope chain? So if we have the following function: function a() { var a = 'function a'; function b() { var b = 'function b'; alert (a); //will be function a, without keyword this alert (this.a); //

This question already has an answer here: Cases where 'this' is the global Object in Javascript 4 answers For obvious reasons, in JavaScript, the following two calls are different: foo.bar(); var bar = foo.bar; bar(); Namely, in the first call, this is the foo object. In the second, it's a reference to the global scope. However, the following example is a little less intuitive: (foo.bar)(); I would expect it to operate the same way as the second example, but it actually operates the same as the first. That is, this references foo , not the global scope. What are JavaScript's rules for deciding

I try to find address of this pointer, but this code is showing a strange error: #include <iostream> using namespace std; class Base { public: void test() { void *address_of_this =&this; cout<<address_of_this<<endl; } }; int main() { Base k; k.test(); return 0; } //error non-lvalue in unary'&' Can you explain this error ? Also point that what is illegal in taking address of this ? this is a pointer containing the address to the "current object". It is not a variable that is stored somewhere (or could even be changed), it is a special keyword with these properties. As such, taking its address

I'm having difficulty referencing "this" from within a javascript inline function, within an object method. var testObject = { oThis : this, testVariable : "somestring", init : function(){ console.log(this.testVariable); // outputs testVariable as expected this.testObject.submit(function(){ var anotherThis = this; console.log(this.testVariable) // undefined console.log(oThis.testVariable) // undefined console.log(testObject.testVariable) // outputs testVariable console.log(anotherThis.testVariable) // undefined } } How do I access this.testVariable from within the submit function? I'm also

After learning Java for sometime, its the first time the use of this keyword has confused me so much. Here is how I got confused. I wrote the following code: class BasicInheritanceTest3Base{ private int x = 0; public int y; public void a() { x++; this.x++; System.out.println("BasicInheritanceTest3Base.a()"); b(); this.b(); System.out.println(x); System.out.println(y); } public void b(){ System.out.println("BasicInheritanceTest3Base.b()"); } } public class BasicInheritanceTest3 extends BasicInheritanceTest3Base { private int x = 3; public int y = 2; public void b() { System.out.println(

In a function, how to you assign this a new value? Luchian Grigore You can't. 9.3.2 The this pointer [class.this] 1 In the body of a non-static (9.3) member function, the keyword this is a prvalue expression whose value is the address of the object for which the function is called. [...] (emphasis & link mine) You can modify the object this points to, which is *this . For example: struct X { int x; void foo() { this->x =3; } }; The method modifies the object itself, but something like this = new X is illegal. You can assign the object this points at: *this = XY; But you can't assign the direct