"my" variables don't work with symbolic

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

When I have a list declared with my, it doesn't let use a symbolic reference to get to it. Here's my code:

#!/usr/local/bin/perl5.00503

@foo_list    = (1,2,3);
my @bar_list = (4,5,6);

my $src  = "foo";
my @list = @{"${src}_list"};
print "length = " . scalar @list . "\n";

$src  = "pnotes";
@list = @{"${src}_list"};
print "length = " . scalar @list . "\n";
[download]

The output is:

length = 3
length = 0
[download]

What's the deal? Why do only non-my variables work?

Comment on "my" variables don't work with symbolic Select or Download Code

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Re: "my" variables don't work with symbolic by davorg (Chancellor) on May 18, 2001 at 12:31 UTC
<rant type="symbolic references"> Symbolic references are bad. Don't use symbolic references. `use strict` prevents you from using symbolic references for a good reason. Read Dominus' article for more details on why symbolic references are a really bad idea. </rant> Do it like this instead: `my %list; $list{foo} = [1, 2, 3]; $list{bar} = [4, 5, 6]; my $src = 'foo'; my @list = @{$list{$src}}; print 'length = ', scalar @list, "\n"; # or... $src = 'bar'; print 'length = ', scalar @{$list{$src}}, "\n";` [download] -- <http://www.dave.org.uk> "Perl makes the fun jobs fun and the boring jobs bearable" - me	[reply] [d/l]
Re: "my" variables don't work with symbolic by stephen (Priest) on May 18, 2001 at 08:11 UTC
From perlman:perlref: Only package variables (globals, even if localized) are visible to symbolic references. Lexical variables (declared with my()) aren't in a symbol table, and thus are invisible to this mechanism. Which is another good reason to avoid them except in extreme and carefully-controlled circumstances... stephen	[reply]