[OSM-talk] JOSM wishlist: forget and undo download

[Frederik Ramm]

Hi,

>> This is when I wish I could "undo" one download batch.  Or make 
>> JOSM "forget" that it downloaded an area that I select.

> This feature was requested Yesterday by Matthias Julius :-)
> Sounds like a popular one. I've added it to JOSM's trac:
> http://josm.eigenheimstrasse.de/ticket/148

I've implemented a "forget" action (accessible from the data menu) in 
this preview:

http://www.remote.org/frederik/tmp/josm-with-forget.jar

This method will remove everything that is currently selected and not 
referenced from non-selected items, without flagging it as "to be 
deleted on the server".

Can someone check if this works ok with mappaint?

A potential problem with this is that even deleted items count towards 
references, so you cannot "forget" a segment if you have deleted the way 
that contained the segment - the way still holds a reference to the 
segment, but you cannot "forget" the way as it is invisible! The reason 
for also counting deleted items is that you could undo the deletion 
anytime (but you cannot undo the forgetting - it is recorded nowhere), 
and thus if you first delete a way, then forget the segments, then undo 
the deletion, you end up with an incomplete way, or if the same thing 
happens with segments and nodes, you have an invalid segment.

Would the function be useful as it is? Should it refuse to "forget" 
items which have unsaved changes?

Bye
Frederik

-- 
Frederik Ramm  ##  eMail frederik at remote.org  ##  N49°00.09' E008°23.33'