Re: Interest in selectively deleting history entries.

[Daniel J Sebald]

On 09/21/2014 04:23 PM, Philip Nienhuis wrote:
> Daniel Sebald wrote
> > On 09/21/2014 12:50 PM, Philip Nienhuis wrote:
> > > Daniel Sebald wrote
> > > > I'm curious what people's thoughts are on the ability to selectively
> > > > delete individual lines of history.  What I see it used for, in
> > <snip>
> > > And it doesn't only hold for Octave but also for shells etc.
> >
> > Yes, I know.  At least in that case one can clear the screen fairly
> > quickly.
>
> Sure, but it remains in the shell's history, also for a looong time.

OK, but out of our control.

[snip]

> > > All of this makes me assume that the history entry number makes most
> > > sense
> > > as a per-session counter. But that's just me.
> >
> > It is per-session, yes.
>
> I'd say just forget about the re-mapping then:
>
> (1) It would add a potentially confusing interpretation layer over command
> sequences;

By mapping I meant that the command list needs to include an index 
number if it doesn't have one already.  If a line is deleted, one can no 
longer compute the line number from where it is in the list.


> (2) Your motives appear to lie primarily in the GUI, with wiping inadvertent
> lines containing sensitive info.

Yes, that's correct.  I myself tend to not use history that much other 
than to hit up arrow a few times.  I generally edit scripts in a file 
and run them.  But now with a GUI, inadvertent passwords are more visible.


> Now in the GUI it is extremely easy to select a block of lines with the
> mouse cursor and copy them into the editor / terminal / whatever. So I see
> little need to painstakingly keep track of what history line number holds
> which command, as command and blocks of commands can much more easily be
> selected with scroll bars / arrow / PGUP / PGDN keys and a mouse cursor
> swipe.
> IOW, the need for some specific parts of the history command set gets moot
> in the GUI.

That's correct.  The GUI doesn't include line numbers in the history 
window.  However, to allow deleting a line from history requires the GUI 
to send a line number to be precise.


> (3) Maybe replace a wiped line by a (hidden?) comment (##) if line numbering
> is to remain consecutive (w/o holes).

That would be another way of doing it.  If there is a hidden placeholder 
in the list, one could still compute the line number without having to 
store it along with the command.

Dan