Re: Problem with how to assign an array
"Steven W. Orr" writes:
> 517 > r=($(eval echo "\${${a_all[1]}[@]}"))
If you use $(eval echo ...) you are almost always doing it wrong.
eval "r=(\"\${${a_all[1]}[@]}\")"
Andreas.
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Re: bash tab variable expansion question?
Eric Blake writes: > On 02/24/2011 03:14 PM, Michael Kalisz wrote: >> $ echo $PWD/ >> will expand the $PWD variable to your current directory >> >> while in bash, version 4.2.0(1)-release: >> >> $ echo $PWD/ >> will just escape the $ in front of the $ variable i.e: >> >> $ echo \$PWD/ >> The shell-expand-line (Ctrl-Alt-e) works but before I could use just TAB >> >> Any hints why? Any way to get the 4.1 behavior in 4.2? >> >> Can someone confirm... Is this a bug or a feature? > > I'm not the developer, but in my mind, this is a welcome feature. Looks like you didn't read what Michael wrote. > TAB-completion should NOT modify what I typed, Except that it does. $PWD/ and \$PWD/ are quite different things. Andreas. -- Andreas Schwab, sch...@linux-m68k.org GPG Key fingerprint = 58CA 54C7 6D53 942B 1756 01D3 44D5 214B 8276 4ED5 "And now for something completely different."
Re: bash tab variable expansion question?
On Friday 25 Feb 2011 05:15:24 Eric Blake wrote: > On 02/24/2011 03:14 PM, Michael Kalisz wrote: > > $ echo $PWD/ > > will expand the $PWD variable to your current directory > > > > while in bash, version 4.2.0(1)-release: > > > > $ echo $PWD/ > > will just escape the $ in front of the $ variable i.e: > > > > $ echo \$PWD/ > > The shell-expand-line (Ctrl-Alt-e) works but before I could use just TAB > > > > Any hints why? Any way to get the 4.1 behavior in 4.2? > > > > Can someone confirm... Is this a bug or a feature? > > I'm not the developer, but in my mind, this is a welcome feature. > TAB-completion should NOT modify what I typed, and I consider the 4.1 > behavior to be the bug. Maybe, but then it shouldn't escape the $ either, as the OP is reporting for 4.2 (I don't have a 4.2 handy to test it). -- D.
Re: bash tab variable expansion question?
On Fri, Feb 25, 2011 at 5:46 PM, Davide Brini wrote: > On Friday 25 Feb 2011 05:15:24 Eric Blake wrote: > > > On 02/24/2011 03:14 PM, Michael Kalisz wrote: > > > $ echo $PWD/ > > > will expand the $PWD variable to your current directory > > > > > > while in bash, version 4.2.0(1)-release: > > > > > > $ echo $PWD/ > > > will just escape the $ in front of the $ variable i.e: > > > > > > $ echo \$PWD/ > > > The shell-expand-line (Ctrl-Alt-e) works but before I could use just > TAB > > > > > > Any hints why? Any way to get the 4.1 behavior in 4.2? > > > > > > Can someone confirm... Is this a bug or a feature? > > > > I'm not the developer, but in my mind, this is a welcome feature. > > TAB-completion should NOT modify what I typed, and I consider the 4.1 > > behavior to be the bug. > > Maybe, but then it shouldn't escape the $ either, as the OP is reporting > for > 4.2 (I don't have a 4.2 handy to test it). > > Agree, $ should not be escaped here which is different from pathname completion. -- Clark J. Wang
Re: bash tab variable expansion question?
On Fri, Feb 25, 2011 at 1:15 PM, Eric Blake wrote: > On 02/24/2011 03:14 PM, Michael Kalisz wrote: > > $ echo $PWD/ > > will expand the $PWD variable to your current directory > > > > while in bash, version 4.2.0(1)-release: > > > > $ echo $PWD/ > > will just escape the $ in front of the $ variable i.e: > > > > $ echo \$PWD/ > > The shell-expand-line (Ctrl-Alt-e) works but before I could use just TAB > > > > Any hints why? Any way to get the 4.1 behavior in 4.2? > > > > Can someone confirm... Is this a bug or a feature? > > I'm not the developer, but in my mind, this is a welcome feature. > TAB-completion should NOT modify what I typed, It's not true, see this discussion: http://lists.gnu.org/archive/html/bug-bash/2011-02/msg00163.html > and I consider the 4.1 > behavior to be the bug. I'd like to view it as a feature. ;) > Consider if I have parallel directory > structures a/c and b/c. If I do: > > d=a > $d/c/test > d=b > $d/c/test > > I want to run two different programs. Now, instead of a one-letter > name, consider that it is something longer, like $HOME. If typing TAB > expands the variable, instead of keeping it intact, then I can't do: > > $HOME/c/t-TAB > $HOME=b > UP-UP-ENTER > > to repeat my test in a new directory, since tab completion wiped out > that I want to evaluate $HOME every time. (The same goes for command > substitution - bash should never pre-maturely lock me in to a single > expansion during tab completion.) > > -- > Eric Blake ebl...@redhat.com+1-801-349-2682 > Libvirt virtualization library http://libvirt.org > > -- Clark J. Wang
Re: Problem with how to assign an array
On Thu, Feb 24, 2011 at 06:59:02PM -0500, Steven W. Orr wrote:
> I intentionally used the star instead of the atsign because I'm taking
> advantage of the fact that these array elements all have no whitespace. So,
> after the assignment to a_all, the value of a[0] is equal to the single
> string represented by "${a1[*]}" (with quotes).
So you're trying to make an array of arrays? To fake a two-dimensional
matrix? Should've said so.
The only sane way to do this is to make an associative array whose
keys are a tuple of the indices you want. (Or, if the indices are
strictly numeric, and bounded, you can do it with regular sparse
non-associative arrays by making the keys i*100+j where 100 is some
constant chosen to be larger than the bound on j.)
And, of course, there's always "don't write it in bash". That's often
a sane answer.
AA example:
declare -A big
big[$i,$j]=foo
Numeric index example:
big[i*100+j]=foo
If you actually wanted an "array of lists" or something that's *not*
mimicking a matrix, then, well, good luck. (Did I mention that there
are other languages besides bash? Some of them actually HAVE such data
structures.)
Re: bash tab variable expansion question?
On Fri, Feb 25, 2011 at 09:46:58AM +, Davide Brini wrote: > Maybe, but then it shouldn't escape the $ either, as the OP is reporting for > 4.2 (I don't have a 4.2 handy to test it). I actually noticed this quite recently, but didn't think to bring it up. I had just typed some "cd" command, and then realized I wanted to view a file in the directory where I had just been. So instead of changing directory again, I typed "cd $OLDPWD/foo" -- and the $OLDPWD became \$OLDPWD and did not do as I wished. Fortunately the workaround was simple enough -- once the filename had been completed I went back and x'ed out the \.
Re: bash tab variable expansion question?
Greg Wooledge writes: > Fortunately the workaround was simple enough -- once the filename had > been completed I went back and x'ed out the \. Or use ~-/. Andreas. -- Andreas Schwab, sch...@linux-m68k.org GPG Key fingerprint = 58CA 54C7 6D53 942B 1756 01D3 44D5 214B 8276 4ED5 "And now for something completely different."
Bash-4.1 Official Patch 10
BASH PATCH REPORT = Bash-Release: 4.1 Patch-ID: bash41-010 Bug-Reported-by:Stephane Jourdois Bug-Reference-ID: Bug-Reference-URL: http://lists.gnu.org/archive/html/bug-bash/2010-05/msg00165.html Bug-Description: The expansion of the \W prompt string escape sequence incorrectly used strcpy to copy overlapping strings. Only memmove works in this case. Patch (apply with `patch -p0'): *** ../bash-4.1-patched/parse.y 2009-12-30 12:51:42.0 -0500 --- parse.y 2011-02-24 16:40:48.0 -0500 *** *** 5153,5157 t = strrchr (t_string, '/'); if (t) ! strcpy (t_string, t + 1); } } --- 5153,5157 t = strrchr (t_string, '/'); if (t) ! memmove (t_string, t + 1, strlen (t)); } } *** ../bash-4.1-patched/y.tab.c 2009-12-30 12:52:02.0 -0500 --- y.tab.c 2011-02-24 16:50:27.0 -0500 *** *** 7482,7486 t = strrchr (t_string, '/'); if (t) ! strcpy (t_string, t + 1); } } --- 7482,7486 t = strrchr (t_string, '/'); if (t) ! memmove (t_string, t + 1, strlen (t)); } } *** *** 8244,8246 } #endif /* HANDLE_MULTIBYTE */ - --- 8244,8245 *** ../bash-4.1-patched/patchlevel.h2009-10-01 16:39:22.0 -0400 --- patchlevel.h2010-01-14 09:38:08.0 -0500 *** *** 26,30 looks for to find the patch level (for the sccs version string). */ ! #define PATCHLEVEL 9 #endif /* _PATCHLEVEL_H_ */ --- 26,30 looks for to find the patch level (for the sccs version string). */ ! #define PATCHLEVEL 10 #endif /* _PATCHLEVEL_H_ */ -- ``The lyf so short, the craft so long to lerne.'' - Chaucer ``Ars longa, vita brevis'' - Hippocrates Chet Ramey, ITS, CWRUc...@case.eduhttp://cnswww.cns.cwru.edu/~chet/
Re: Problem with how to assign an array
On 2/25/2011 4:22 AM, Andreas Schwab wrote:
"Steven W. Orr" writes:
517> r=($(eval echo "\${${a_all[1]}[@]}"))
If you use $(eval echo ...) you are almost always doing it wrong.
eval "r=(\"\${${a_all[1]}[@]}\")"
Andreas.
Thanks. I changed things of the form
r=($(eval "echo "\${${a_all[1]}[@]}\""))
to
eval "r=(\"\${${a_all[1]}[@]}\")"
One place where I can't see how to eliminate the construct is where I pass in
the name of an array and parse it using set
set -- $(eval echo \"\${$name[@]}\")
would I be better off with something like
eval "set -- \"\${$name[@]}\""
?
TIA
--
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happened but none stranger than this. Does your driver's license say Organ ..0
Donor?Black holes are where God divided by zero. Listen to me! We are all- 000
individuals! What if this weren't a hypothetical question?
steveo at syslang.net
Re: bash tab variable expansion question?
Look at the following example: # touch 'file name with a space' if I press # ll file then I get: # ll file\ name\ with\ a\ space -rw-r--r-- 1 root sys 0 Feb 25 13:10 file name with a space The backslash '\' which reminds me of: # cd /tmp # mkdir hello # cd $PWD/hello Which gives me: # cd \$PWD/hello instead # cd /tmp/hello (if I press ESC Ctrl-e twice it when the \$PWD is diplayd the it will expand the $PWD variable correctly) Anyhow...This "feature" seems new to 4.2.0 and differs from previous bash versions. Any hints how the get back the old behavior? //Michael
Re: bash tab variable expansion question?
What do you mean? ~-/. is no equal to $PWD On 25 Feb, 16:03, Andreas Schwab wrote: > Greg Wooledge writes: > > Fortunately the workaround was simple enough -- once the filename had > > been completed I went back and x'ed out the \. > > Or use ~-/. > > Andreas. > > -- > Andreas Schwab, sch...@linux-m68k.org > GPG Key fingerprint = 58CA 54C7 6D53 942B 1756 01D3 44D5 214B 8276 4ED5 > "And now for something completely different."
Re: bash tab variable expansion question?
gnu.bash.bug wrote: > Andreas Schwab wrote: > > Greg Wooledge wrote: > > > directory again, I typed "cd $OLDPWD/foo" -- and the $OLDPWD > > > became \$OLDPWD and did not do as I wished. > > > > Or use ~-/. > > What do you mean? > > ~-/. is no equal to $PWD No. But it is similar to $OLDPWD which is what Greg had written about. Bob
