Usage of on(…):
attach an inline event handler using .on() without any callback

How to attach an inline event handler using .on() without any callback?

Compact syntax with timing methods:

1 $('.some').on('click').doSome().jQueryStuff();

The return value of .on() is an inline handler if the callback function is skipped or given as jQuery token $.

Compare this to the old way with more syntactic fluff:

1 $('.some').on('click', function(){
2   $(this).doSome().jQueryStuff();
3 });