Javascript run() function

Question

var test = function(msg) {
  alert(msg)
};

(new test("hi")).run();
(new test("hello")).run();

When I run above javascript code, I am able to get alert "hi". But alert "hello" is not coming up.

Anybody can explain what is above, I am completely new to this. Only I know is that "test" is a function
What is run() method does?, because when I removed run in the above code, I am able to see both alerts, pls help...
```
var test = function(msg) {
  alert(msg)
};

(new test("hi"));
(new test("hello"));
```

Even that works.... Then what is "run" and "new" does?. Any ideas? — , Jul 14 '15 at 08:34

score 9 · Accepted Answer · edited May 23 '17 at 11:58

9

Simple, there is no run function, when your code runs (new test("hi")).run() it runs the (new test("hi")) part first, and then errors on the run so the second line is never executed.

If you want to call a function, call it:

test("hi");

Don't run functions (that are not constructors) as constructors. Here is what new does.

edited May 23 '17 at 11:58

Community

1
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answered Jul 14 '15 at 08:34

Benjamin Gruenbaum

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Or rather, "only run functions intended to be constructors as constructors." :) – Amadan Jul 14 '15 at 08:36
1

And this explains why it doesn't go on to run the next line :) – TaoPR Jul 14 '15 at 08:37

mechanicals · Answer 2 · 2015-07-14T08:46:45.933

"run" is not a defined function. Even if you replace "run" by "xyz"|| "abc" or any other random function name which is not defined, the code above will work in the same way.

var test = function(msg) {
  alert(msg)
};

/** test("hi") getting called, then xyz() throws a javascript error **/ 
(new test("hi")).xyz();

/** No Execution as there was an error on previous line **/ 
(new test("hello")).xyz();

Its's just that initially the "test" function is called once and when it encounters a .run() which is not defined, it throws an error and execution stops.

score 0 · Answer 3 · answered Feb 18 '19 at 22:10

Couldn't you use a find & Replace routine to read the cookie and then replace it with ''?

I have not been able to delete all path cookies using all of the tips above and am still playing with it, but I did make a bookmarklet to extract all the cookies and put them in an iframe so that you can copy&paste them.

javascript: var c=document.cookie;if (c==''){alert('This site didn\'t give you any cookies at all.\nNot a single one!');}else{w=window.open('','Links','scrollbars,resizable,width=400,height=600');w.document.write(c);    }

Javascript run() function

3 Answers3