Why checkbox just ignoring event.namespace, and fires all the bound handlers

The jQuery .on() and .trriger() methods provide a way to bind and fire multi handlers on one single element by specifying event.namespace, without disturbing each other.

However, I found namespace is not working for checkbox, it just fires all the bound handlers which are attached in different namespaces.

The code is very simple, something like:

$('checkbox').on('click.n1',func1).on('click.n2',func2);

$('checkbox').trigger('click.n1');

Both func1 and func2 would be fired. The same code works fine on other elements.

Is it a BUG? Or did I miss anything for checkboxex?

Thank you for any help!

foo();

function foo() {
  $("#checks input")
  .on('click.checks1',function(){console.log('click.checks1')})
  .on('click.checks2',function(){console.log('click.checks2')});
  $("#checks input").eq(0)
  .trigger('click.checks1');
  $("#radios input")
  .on('click.radios1',function(){console.log('click.radios1')})
  .on('click.radios2',function(){console.log('click.radios2')});
  $("#radios input").eq(0)
  .trigger('click.radios1');
}

<script src="http://ift.tt/1oMJErh"></script>
<div id='checks'>
  <input type='checkbox' />1
  <br>
  <input type='checkbox' />2
  <br>
</div>
<div id='radios'>
  <input type='radio' />1
  <br>
  <input type='radio' />2
  <br>
</div>