> I need to express an insert into a text document - eg, "Insert 'a' at position X". The obvious question that comes up is - how should we define "X"? Perhaps

> I need to express an insert into a text document - eg, "Insert 'a' at position X". The obvious question that comes up is - how should we define "X"? Perhaps using a cursor/rider/however-you-call-it into whatever data structure you're using for editable sequences (since there's a bunch of them) is the preferred solution here? I'm hardly an editor expert but I thought that's how this has been being done for decades (and for some possibly useful but really complicated text representations, numerical indices for positions of operations wouldn't really work very well anyway).