What the ***!!
I have written some behaviour some time ago, which has a
iterative method to determine the width of the text in a text
member. I needed something like this, since charpostoloc was only
available for field text members (according to the documentation).
I was just about sharing this behaviour with you when I saw Sean
Wilsons answer. I tried it and yes charpostoloc also works on text
Directors documentation still sucks! LIke it always has done.