Re: Exponentiation operator

[Chet Ramey]

sanchis@iut-rodez.fr wrote:
> Configuration Information [Automatically generated, do not change]:
> Machine: i386
> OS: linux-gnu
> Compiler: gcc
> Compilation CFLAGS:  -DPROGRAM='bash' -DCONF_HOSTTYPE='i386' 
> -DCONF_OSTYPE='linux-gnu' -DCONF_MACHTYPE='i386-pc-linux-gnu' 
> -DCONF_VENDOR='pc' -DSHELL -DHAVE_CONFIG_H  -I.  -I../bash -I../bash/include 
> -I../bash/lib  -g -O2
> uname output: Linux jade 2.6.8-2-686-smp #1 SMP Mon Jan 24 02:32:52 EST 2005 
> i686 GNU/Linux
> Machine Type: i386-pc-linux-gnu
>
> Bash Version: 2.05b
> Patch Level: 0
> Release Status: release
>
> Description:
>         A syntax error with the expression : a**b**c
>         What is the associativity of the exponentiation operator ?
>
> Repeat-By:
>
> $ echo $((2**3**2))
> bash: 2**3**2: syntax error in expression (error token is "**2")

I made the ** operator associative between bash-2.05b and bash-3.0,
but made it left associative like the rest of the binary operators.
It's more mathematically correct to make it right-associative, so
bash-3.1 will do that.

Chet
--
``The lyf so short, the craft so long to lerne.'' - Chaucer
( ``Discere est Dolere'' -- chet )
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Chet Ramey, ITS, CWRU    chet@case.edu    http://cnswww.cns.cwru.edu/~chet/