Re: Interpretation of escapes in expansions in pattern matching contexts

[Chet Ramey]

On 4/6/13 9:59 PM, Chris F.A. Johnson wrote:

>   In bash, the expansion differs when in  [[ ... ]]:
> 
> $ x=\\x; if [[ x == $x ]]; then echo yes; else echo no; fi
> yes
> $ x=\\x; if [ x == $x ]; then echo yes; else echo no; fi
> no

OK.  The [[ conditional command does pattern matching.  The [ (test)
command does string comparison.  $x expands to `\x' in both cases.

> 
>   But not in ksh93:

I'm going to assume ksh93 dequotes the variable.  I don't know why.

-- 
``The lyf so short, the craft so long to lerne.'' - Chaucer
                 ``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, ITS, CWRU    chet@case.edu    http://cnswww.cns.cwru.edu/~chet/