endEditingFor:nil

I am sure there is a simple answer, but I have not seen it anywhere.


In Hillegass, the method

is edited to archive the document.

One of the calls to stop all editing is:

The documentation says of the argument for "endEditingFor"

Could anyone help me understand then why "nil" is provided as an argument, when it is supposed to be directed at an object using the field editor...in other words...what objects are supposed to be receiving this message. It obviously works, but I am just trying to figure out why.

Thanks as always.