Re: aliases not getting expanded inside functions?

[Carlos Carvalho <carlos@fisica.ufpr.br>]

Zefram (zefram@fysh.org) wrote on 3 January 2003 18:54:
 >That's the "p" (*small* p) flag.  Phil was demonstrating the "P"
 >(*capital* P) parameter expansion flag, which zshexpn(1) describes thus:
 >
 >#        P      This  forces  the value of the parameter name to be
 >#               interpreted as  a  further  parameter  name,  whose
 >#               value  will be used where appropriate. If used with
 >#               a nested parameter  or  command  substitution,  the
...

Oops... This didn't appear in my manual. After some digging I found
that I was reading the old manual, for zsh 3, when this didn't exist
yet. Now I've cleaned the remnants of the old installation and I can
see the current manuals. Impressive! I'm starting to use some of the
new features, but it's just the beginning :-)

 >To use this kind of parameter alias for setting, you can do
...
 >% : ${(P)foo::=xxx}
 >% echo ${(P)foo}
 >xxx
 >% echo $foo $bar
 >bar xxx
 >
 >which also works where foo is an array reference such as "array[3]".

Thanks, I think I understood now. I wouldn't call it the simplest
thing to find out... In my case I'd have to do

% a[1]=name1 a[2]=name2 etc.
% b[1]=b_name1 b[2]=b_name2 etc.

and then to do the transfer

for ((i=1; i< number-of-elements; i++)) {
	: ${(P)b[i]::=$a[i]}
}

However this is too much of a contortion to be useful... Is there a
way to do the whole assignment without a loop? Something like
${(P)b::=$a} or similar (yes, this one cannot work of course).

It seems that putting assignments like b_name1=$name1 b_name2=$name2
etc. in a function and simply calling it ends up working better. The
only advantage of using the loop above is that it's independent of the
number of elements, but I think this independence isn't worth the
trouble.

Thanks a lot to the developers in the list, the level of support is
amazing.