Interpret array elements as actual Perl?

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

Hello again Monks...
Are there any circumstances under which Perl will interpret a scalar variable as actual Perl? This

use warnings;
use strict;

my @commands = 'print "hello", print "world"';
foreach my $command(@commands) {
    $command;
    }
[download]

yields the message "Useless use of private variable in void context at script.pl line 6".

Comment on Interpret array elements as actual Perl? Download Code

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Re: Interpret array elements as actual Perl? by Fletch (Bishop) on May 28, 2004 at 16:59 UTC
`perldoc -f eval`	[reply] [d/l]
Re: Re: Interpret array elements as actual Perl? by McMahon (Chaplain) on May 28, 2004 at 17:02 UTC
neat	[reply]
Re: Interpret array elements as actual Perl? by calin (Deacon) on May 28, 2004 at 18:24 UTC
You'd better go with an array of anonymous subs, IMHO. `my @commands = ( sub {print "hello\n"}, sub {print "world\n"} ); foreach my $command (@commands) { &{$command}; }` [download]	[reply] [d/l]
Re: Re: Interpret array elements as actual Perl? by meetraz (Hermit) on May 28, 2004 at 18:38 UTC
Isn't this better written as: `use strict; my @commands = ( sub {print "hello\n"}, sub {print "world\n"}, ); foreach my $command (@commands) { $command->(); # Or use args like this: $command->($arg1,$arg2); }` [download] (Using `subname()` instead of `&subname`)	[reply] [d/l] [select]
Re: Re: Re: Interpret array elements as actual Perl? by calin (Deacon) on May 28, 2004 at 18:57 UTC
I think it's a matter of taste. It may look cleaner in a cascaded dereference construct, but I tend to avoid it as much as I can for religious reasons (it looks OOPish ;) ) You can pass arguments with the ampersand syntax too: `&$command ($arg1, $arg2);` Update: There are issuse with a bare & call and @_, see code: `$ perl sub foo { my $x = sub {print "@_"}; &{$x}; } foo qw/bar baz/; ^D bar baz` [download] If you don't want to transfer @_ use `&{$x} ();` (or `$x->();`)	[reply] [d/l] [select]