CCNA, CCNP, MCSA, CCNA Final Exam, All Answer Test Module With 100/100

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? Source: Tips4all