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Re: PATCH: small parameter fix
- X-seq: zsh-workers 5686
 
- From: Peter Stephenson <pws@xxxxxxxxxxxxxxxxx>
 
- To: zsh-workers@xxxxxxxxxxxxxx (Zsh hackers list)
 
- Subject: Re: PATCH: small parameter fix
 
- Date: Mon, 08 Mar 1999 16:55:08 +0100
 
- In-reply-to: "Bart Schaefer"'s message of "Mon, 08 Mar 1999 01:01:01 NFT."             <14051.37325.463850.598816@xxxxxxxxxxxxxxxxxxxxx> 
 
- Mailing-list: contact zsh-workers-help@xxxxxxxxxxxxxx; run by ezmlm
 
>  > 
>  >   ${${...}[...]}
>  > 
>  > previously didn't really work: if the inner ${...} produced an array
>  > with only one element, the outer ${...} treated it as a string and the 
>  > subscript gave the n'th character.
> 
> AHA!  This must be the reason that "${${(@)...}...}" is required in so
> many mystifying circumstances.  I, too, would like to hear whether the
> previous behavior was intentional ... this change does potentially
> break scripts, including I think 3.0.5 scripts, so we'd better tread
> carefully.
in particular it has this effect:
% print "${$(uname -n)[1]}"
ibmth
where you might guess $(...) in quotes produced a scalar for subscripting
--- indeed it did, but the subscripting decided to treat it as an array
element.  In fact, since the nested substitution recognises the quotes
whereas the subscripting doesn't, you get,
% print "${${path}[1]}"
/home/user2/pws/bin /home/user2/pws/links /home/user2/pws/mh/bin
/home/user2/pws/scripts /usr/local/bin /usr/sue/bin /usr/bin /usr/bin/X11
/usr/ucb /usr/local/bin/X11 /cern/pro/bin /usr/local/cap /etc .
(wrapped a bit --- well, you don't get that, but I do) which is distinctly
on the strange side.  I would suggest that in quotes the old behaviour
character-subscripting behaviour is the right one.
-- 
Peter Stephenson <pws@xxxxxxxxxxxxxxxxx>       Tel: +39 050 844536
WWW:  http://www.ifh.de/~pws/
Dipartimento di Fisica, Via Buonarroti 2, 56127 Pisa, Italy
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