Re: Weird reset-prompt behavior

[Bart Schaefer <schaefer@xxxxxxxxxxxxxxxx>]

On Aug 23, 10:49pm, Björn wrote:
} Subject: Weird reset-prompt behavior
}
} I'm pretty new to zsh so i don't know if this is already known, but i 
} discovered a pretty weird behavior when resetting the prompt and rprompt

To address your specific problem, you shouldn't need zle-line-init at
all for this.  The editor always starts in the same state with the
viins keymap, so just set up PROMPT and RPROMPT in your precmd and let
zle-keymap-select do all the rest of the work.

However, your example does point out a bit of odd behavior.  Ignoring
zle-keymap-select for the moment, try the following in a new shell.

torch% n=0
torch% zle-line-init() { RPS1=$[n++]; zle reset-prompt }
torch% zle -N zle-line-init
torch% 

Hmm.  Why didn't the right prompt appear when the new left prompt was
printed after creating the widget?  It gets stranger, though; enter
a command, such as "print $n" (using a 40-column terminal below so as
to avoid line-wrapping) ...

torch% print $n
1
torch%                                0

Well, OK, n=1 and RPS1=0, which is sort of as expected.  But now it gets
really strange.  Begin typing anything (I started to type "print" again
in the cut-and-paste below):

torch% p                              1

RPS1 just belatedly updated itself!  I'm pretty sure zle-line-init was
not called again here, so there's some kind of delayed reaction (the
$[n++] did happen when the widget was created, but the display was
never updated).  Further demonstration, again starting fresh:

torch%  zle-line-init() {
function> zle -R $SECONDS
function> PS1="$SECONDS %# "
function> zle reset-prompt
function> }
torch% zle -N zle-line-init
torch% 
42

Now start to type anything, and the screen suddenly looks like this:

torch%  zle-line-init() {
function> zle -R $SECONDS
function> PS1="$SECONDS %# "
function> zle reset-prompt
function> }
torch% zle -N zle-line-init
42 % p

Note the "torch%" prompt has been updated and the "zle -R" output has
been erased.  (Things are even stranger if I used "zle -M" instead,
but leave that aside for now.)  Proceeding ...

function> }
torch% zle -N zle-line-init
42 % print $SECONDS
156
42 % 
156

This proves that zle-line-init ran when the editor started, but that
Again start to type ...

42 % print $SECONDS
156
156 % p

I almost suspect this is just a matter of a fflush() that hasn't yet
happened, except for that $[n++] oddity in the very first example.