completing second argument of cd

completing second argument of cd

[Peter Stephenson]

I don't remember seeing a function like this posted before... it's for
use with compctl and completes the second argument of cd, i.e. it
tries to find a possible new directory by altering an occurrence of
the existing cd argument in $PWD.

e.g.

% pwd
/home/sgi/pws/lgt/su2/phase/data/12_6/2.4
% cd 12_6 <TAB>      ->      cd 12_6 8_4
~/lgt/su2/phase/data/8_4/2.4

(yes, I wrote this to save typing three characters :-))

The comment about the bug refers to this:
% pwd
/groupfs/schierholz3/stephens/b6p00kp1550.bub/rho
% cd rho pion
cd: no such file or directory:
/groupfs/schiepionlz3/stephens/b6p00kp1550.bub/rho

(I've split the error message):  in other words, there's a perfectly
good directory /groupfs/schierholz3/stephens/b6p00kp1550.bub/pion, but
the shell has decided willy-nilly that the first rho it finds is the
one to change.  It's a philosophical bug, if you consider zsh is
supposed to be smart :-).

Here's the function.


# cdswap:  function to be used for completion of second argument of cd
# or pushd.
# Usage:
#   compctl -g '*(-/)' -x 'p[2]' -K cdswap -- cd pushd
# May be combined with $CDPATH searching functions, e.g.:
#   compctl -g '*(-)' -x 'p[2]' -K cdswap -- + -K cdmatch -S / -q cd pushd
# Peter Stephenson (pws@ifh.de)

# reset options after use:  no reply if no match
setopt localoptions nullglob
# stripped bits of PWD not to be eligible for globbing:
# use zsh-style arrays
unsetopt globsubst ksharrays

local args
# args looks like (cd old new)
read -Ac args

# Always use first match for $args[2] (this is how cd works regardless
# of whether resulting directory exists --- is this a bug?)
reply=(${PWD%%$args[2]*}*${PWD#*$args[2]}~$PWD)
reply=(${${reply#${PWD%%$args[2]*}}%${PWD#*$args[2]}})


-- 
Peter Stephenson <pws@ifh.de>       Tel: +49 33762 77366
WWW:  http://www.ifh.de/~pws/       Fax: +49 33762 77330
Deutches Electronen-Synchrotron --- Institut fuer Hochenergiephysik Zeuthen
DESY-IfH, 15735 Zeuthen, Germany.

Re: completing second argument of cd

[Zoltan Hidvegi]

> I don't remember seeing a function like this posted before... it's for
> use with compctl and completes the second argument of cd, i.e. it
> tries to find a possible new directory by altering an occurrence of
> the existing cd argument in $PWD.

Have a look at Misc/compctl-examples and Functions/cdmatch2.  It is in the
zsh distribution since beta17, and it was in my private distribution much
before that.

Cheers,

Zoltan

Re: completing second argument of cd

[Bart Schaefer]

On Jul 22,  4:59pm, Zoltan Hidvegi wrote:
} Subject: Re: completing second argument of cd
}
} Have a look at Misc/compctl-examples and Functions/cdmatch2.

These examples would be a lot more helpful if they included some comments
explaining which of zsh's baroque parameter manipulation features they are
(ab)using, and why.  It's pretty obvious that Peter's function and Zoltan's
are both doing the same basic thing; but I have NO idea what reply[(r)]
in Zoltan's version means, since according to the documentation the (r)
should be followed by a pattern.

-- 
Bart Schaefer                             Brass Lantern Enterprises
http://www.well.com/user/barts            http://www.nbn.com/people/lantern

New male in /home/schaefer:
>N  2 Justin William Schaefer  Sat May 11 03:43  53/4040  "Happy Birthday"

Re: completing second argument of cd

[Zoltan Hidvegi]

> On Jul 22,  4:59pm, Zoltan Hidvegi wrote:
> } Subject: Re: completing second argument of cd
> }
> } Have a look at Misc/compctl-examples and Functions/cdmatch2.
> 
> These examples would be a lot more helpful if they included some comments
> explaining which of zsh's baroque parameter manipulation features they are
> (ab)using, and why.  It's pretty obvious that Peter's function and Zoltan's
> are both doing the same basic thing; but I have NO idea what reply[(r)]
> in Zoltan's version means, since according to the documentation the (r)
> should be followed by a pattern.

There is a pattern, don't you see that :-) ?  There is an empty pattern.

The

[[ ${#reply[(r),-1]} != 0 ]] && reply[(r)]="''"

line just replaces an empty array element with a '' since zle_tricky does
not properly quotes empty strings.  Unfortunately replacing the empty sring
to '' in quotename() does not help since it messes up completion if there
is an empty string in the list.

Zoltan