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From: Ch Lamprecht on 21 Sep 2006 03:57
Tad McClellan wrote:
> David Squire <David.Squire(a)no.spam.from.here.au> wrote:
>
>>ed wrote:
>
>
>>> my %h = %_;
>>
>>Hmmm. Is there such a variable s %_?
>
>
>
> Yes there is. (but it doesn't do anything for the OP.)
>
> There is a $_ variable, so then there is also @_ and %_ (and
> a few more) variables.
>
>
> eg: Since there is a $@ variable, this works fine, even with strictures:
^^^^^^^^^^^^^^^^^^^^^^^^^^^^


perlvar:

Perl identifiers that begin with digits, control characters, or punctuation
characters are exempt from the effects of the package declaration and are always
forced to be in package main; they are also exempt from strict 'vars' errors.


>
> -----------------
> #!/usr/bin/perl
> use warnings;
> use strict;
>
> @@ = qw/foo bar/;
> print "$_\n" for @@;
>
> %@ = qw/foo FOO bar BAR/;
> print "$_ => $@{$_}\n" for keys %@;
> -----------------
>
>

so this will work with any variable name starting with a control character:

use warnings;
use strict;

@? = qw/foo bar/;
print "$_\n" for @?;

%? = qw/foo FOO bar BAR/;
print "$_ => $?{$_}\n" for keys (%?);



Christoph

--

perl -e "print scalar reverse q/ed.enilno(a)ergn.l.hc/"
From: Dr.Ruud on 21 Sep 2006 04:13
Ch Lamprecht schreef:

> so this will work with any variable name starting with a
> control character:
>
> use warnings;
> use strict;
>
> @? = qw/foo bar/;
> print "$_\n" for @?;
>
> %? = qw/foo FOO bar BAR/;
> print "$_ => $?{$_}\n" for keys (%?);

I see no "variable name starting with a
control character" in your example.

--
Affijn, Ruud

"Gewoon is een tijger."


From: Ch Lamprecht on 21 Sep 2006 04:55
Dr.Ruud wrote:
> Ch Lamprecht schreef:
>
>
>>so this will work with any variable name starting with a
>>control character:
>>
>>use warnings;
>>use strict;
>>
>>@? = qw/foo bar/;
>>print "$_\n" for @?;
>>
>>%? = qw/foo FOO bar BAR/;
>>print "$_ => $?{$_}\n" for keys (%?);
>
>
> I see no "variable name starting with a
> control character" in your example.
>

Of course you are right.

s/control/punctuation/


--

perl -e "print scalar reverse q/ed.enilno(a)ergn.l.hc/"
From: ed on 21 Sep 2006 14:27
On Wed, 20 Sep 2006 22:31:53 GMT
"John W. Krahn" <someone(a)example.com> wrote:

> ed wrote:
> > I'm having a bit of trouble sending hash elements to sub routines
> > and back.
> >
> > Any help appreciated!
> >
> > sub entry {
> > my $l = shift;
> > my %h = %_;
> >
> > while( ( my $k, my $v ) = each ( %h ) ) {
> > print( "K: $k V: $v\n" );
> > }
> > return(%h);
> > }
> >
> > $h{'stuff'} = "hello";
> > %h = entry( "1", \%h );
> >
> > When run %h becomes empty in entry.
>
> You are calling entry() with a hash reference so you have to
> dereference it inside the sub:
>
> sub entry {
> my $l = shift;
> my $h = shift;
>
> while( my ( $k, $v ) = each ( %$h ) ) {
> print( "K: $k V: $v\n" );
> }
> return %h;
> }


Thank you all very much, Abigail, David and Tad. Problem solved. This
was a very difficult problem for me, I would never have solved it alone.


--
Regards, Ed :: http://www.linuxwarez.co.uk
proud bash person
When Chuck Norris roundhouse kicks people, they do not die of blunt
trauma or tissue damage. They simple lose their will to live.
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