Re: set -A

[Peter Stephenson <pws@xxxxxxx>]

"Bart Schaefer" wrote:
> On Feb 6,  7:01pm, Paul Ackersviller wrote:
> } Subject: set -A
> }
> } unset arr
> } set -A arr "${arr[@]}" first
> } [ ${#arr[@]} = 2 ] && echo "arr[0]='${arr[0]}' arr[1]='${arr[1]}'"
> } 
> } Note the null entry on the start of the array.
> 
> This really has nothing to do with "set -A".
> 
> If you've unset arr, then arr is not an array, and hence ${arr[@]} is
> not an array either, and therefore "${arr[@]}" does not behave like
> an array; rather, it behaves like a string, so putting it in double
> quotes yields the empty string.

But the `@' subscript is not documented to do anything useful for
strings, nor can I see why anyone would assume it was useful in that
case, nor, if they *did* think, that why they would assume that it
produced a null string instead of the usual elision of the argument.  (I
haven't put that very well.)

I think we could safely and consistently have a non-existent parameter
treated as an array in this special case without any negative impact.

The main problem with doing anything is that this part of the code is
particularly ghastly and I shudder at going anywhere near it.

-- 
Peter Stephenson <pws@xxxxxxx>                  Software Engineer
CSR Ltd., Science Park, Milton Road,
Cambridge, CB4 0WH, UK                          Tel: +44 (0)1223 692070


**********************************************************************
The information transmitted is intended only for the person or
entity to which it is addressed and may contain confidential 
and/or privileged material. 
Any review, retransmission, dissemination or other use of, or
taking of any action in reliance upon, this information by 
persons or entities other than the intended recipient is 
prohibited.  
If you received this in error, please contact the sender and 
delete the material from any computer.
**********************************************************************