Thanks, but I'm not sure I want the whole tree to be redrawn when Hidden is toggled. The user might have a big tree, with various directories opened, and I don't like the idea of losing the state the tree is in when Hidden is hit.
What I usually do is toggle it on, close and reopen immediately a dir to see if it has hidden files in it, and then toggle it back off right away.
I have to think about this. Maybe I should add another command to force redraw everything. or maybe middle clicking on "xplor" could trigger that.
Since the state of the tree is simply how it is printed, I don't think there is a way to save it without saving all the tree as it is, as a textual form (string or char). The fact that I'm using directly the printed text as the tree is both a strength and a weakness.
A better way of storing the state of the tree would be to use a real data structure, with nodes, having parents and children, etc. which is probably the more usual way of doing a files manager. But then it would be a bit more complicated and not as acme-ish, that's why I didn't do it (after consideration). But it's probably a fun project to do if you feel like it.
Sorry for the confusion, when I said saving the state I did not mean to save it in textual form, rather to use a data structure to represent the tree, in a way that would allow to manage the folding/unfolding.
I plan to work on this in the weekend, if for nothing else than it'll be fun. I'll try and make it so it will fit well with the Acme/Plan9 way, if it's alright with you, I would like to send you a patch for consideration/review.