David Korn wrote:
> > Is there a way to return a compound variable value from a function
> > without dismanteling each single value first (which would be very
> > painfull in the case when the compound variable has hundreds or
> > thousands of members which itself are compound variables (see
> > http://opensolaris.pastebin.ca/raw/683236 for an example)) ?
> >
> > I've tried the following example but it doesn't really work:
> > -- snip --
> > function g
> > {
> > typeset x=(float x=1 y=2)
> > print $x
> > }
> >
> > typeset l=$(g)
> >
> > print "${l.x}"
> > -- snip --
> >
> > The variable "l.x" is empty in this case.
>
> There are two ways to do this:
>
> FIRST:
>
> function foo
> {
> typeset x=(typeset -lE x=1 y=2)
> print -r "$x"
> }
> eval "l=$(g)"
>
> The eval is needed because ( and ) are only recognized by the parser.
> The quotes are needed around "$x" to prevent expansions.
... but the problem still remains when I want to copy a compound
variable with all members, e.g. $ (d=(typeset -lE x=5.5 y=6.7) ; eval
"j=$(print -- "$d")" ; print ${j.x} ) # ... I guess in such a case the
"eval" is unavoidable, right ?
Another scenario may be object serialisation (where "object" means
"compound variable", e.g. convert compound variable to a string, save
string to a file and load it later again (or send the whole thing via
network etc.)) ... and in all these cases the use of "eval" is... uhm...
a bit scary...
> Note that I used
> typeset -lE
> rather than float. For some reason (I guess a bug), the alias is
> not being expanded so that this is being treated as an indexed
> array rather than a compound assignment.
>
> x=(float x=1 y=2)
> works, but
> typeset x=(float x=1 y=2)
>
> I suspect that this is becasue aliases are only recognized for the
> first word of a command.
>
> SECOND WAY (the recommended way)
>
> function g
> {
> nameref x=$1
> x=(float x=1 y=2)
> }
> g l
*bing* ... I forgot that "nameref" can look into the local variables of
the calling function...
... Thanks! :-)
----
Bye,
Roland
--
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