Re: set -x output of test operator is irretating

[Chet Ramey <chet.ramey@xxxxxxxx>]

Toralf Förster wrote:

> Bash Version: 3.2
> Patch Level: 33
> Release Status: release
>
> Description:
>         I'm wondering why in the example (see below) the right side is prefixed 
> with a '\' wheras the left side is unchanged.
>
> Repeat-By:
>         tfoerste@n22 ~ $ echo "1 2 3 4" | while read a b c d; do [[ "$a" = "$b" || "$a" = "$c" || 
> "$a" = "$d" ]] && echo oops; done
>         + read a b c d
>         + echo '1 2 3 4'
>         + [[ 1 = \2 ]]
>         + [[ 1 = \3 ]]
>         + [[ 1 = \4 ]]
>         + read a b c d
>         ++ echo -ne '\033]0;tfoerste@n22:~\007'

Because the ==/!=/= operators are defined to match the rhs as a pattern
unless it's quoted.  You quoted the original string, and the `set -x'
output is supposed to be re-usable as input, so the trace output is
quoted appropriately.

Chet
--
``The lyf so short, the craft so long to lerne.'' - Chaucer

Chet Ramey, ITS, CWRU    chet@xxxxxxxx    http://cnswww.cns.cwru.edu/~chet/