Programmatically stop Javascript execution in FireFox/FireBug

Question

I am currently debugging complex Javascript/AJAX code written with mootools with FireBug. I am looking for a way to stop the JS execution as if it was a breakpoint programmatically.

Ex:

instructions ...
degugger.breakpoint(); // the execution stops here as if a breakpoint was
                       // manually set
other instructions ...

any idea?

Answer 1

In Firefox, IE, Safari and Chrome (not Opera) you can set the debugger directive.

// your JS code
...
// break here
debugger;

This is extremely useful with Firebug.

Answer 2

you can debug using firebug just open the script tab and blick on the line where you want the execution to stop