Re: Bash prints syntax error when command in $(...) contains case-esac

[Bernd Eggink]

Juergen Gohlke schrieb:
> Configuration Information [Automatically generated, do not change]:
> Machine: i686
> OS: cygwin
> Compiler: gcc
> Compilation CFLAGS:  -DPROGRAM='bash.exe' -DCONF_HOSTTYPE='i686' 
> -DCONF_OSTYPE='cygwin' -DCONF_MACHTYPE='i686-pc-cygwin' 
> -DCONF_VENDOR='pc' -DLOCALEDIR='/usr/share/locale' -DPACKAGE='bash' 
> -DSHELL -DHAVE_CONFIG_H -DRECYCLES_PIDS   -I.  
> -I/home/eblake/bash-3.2.9-11/src/bash-3.2 
> -I/home/eblake/bash-3.2.9-11/src/bash-3.2/include 
> -I/home/eblake/bash-3.2.9-11/src/bash-3.2/lib   -O2 -pipe
> uname output: CYGWIN_NT-5.0 JONA 1.5.24(0.156/4/2) 2007-01-31 10:57 i686 
> Cygwin
> Machine Type: i686-pc-cygwin
>
> Bash Version: 3.2
> Patch Level: 9
> Release Status: release
>
> Description:
>        If a command in $(...) contains a case-esac construction, the 
> bash prints a syntax error instead
>        of executing the code:
>        bash: syntax error near unexpected token `;;'
>
> Repeat-By:
>        A simple example is: x=$(a=4; case $a in 3) echo a=3;; 4) echo 
> a=4;; esac)
>        (typed in an interactive shell or being part of a shell script).
>        The same error has been seen on Windows Vista, Windows XP and 
> Windows2000.
>        The same error has been seen with an earlier version of bash, 
> i.e. 2.05b.0(8)-release
>        If $(...) is replaced by `...`, it works.

The problem is caused by the semi-parenthesized case labels 3) and 4). 
Bash matches the first unpaired right paren (after the 3) with the last 
unpaired left paren (in $( ). Using (3) and (4) instead makes the 
example work.
Unpaired parens are hideous anyway, IMHO.

Regards,
Bernd

--
Bernd Eggink
monoped@sudrala.de
http://sudrala.de