From ed-pm at s5h.net  Tue Nov 13 14:05:43 2007
From: ed-pm at s5h.net (ed)
Date: Tue, 13 Nov 2007 22:05:43 +0000
Subject: [Thamesvalley-pm] perl subroutine refs
Message-ID: <20071113220543.62b81bcd@workstation>

Hi,

I'm trying to do something to compare scriptable plugin methods between
php and perl, but I have a problem in that I cannot figure out how to
do it with strict:

#!/usr/bin/perl

use warnings;
use strict;

my %subs;

sub test {
	print( "Tested\n" );
}

my $l = "test";

$subs{'plugname'} = &$l;
$subs{'plugname'};

The error message insists that this is not possible while using strict
refs, but I'd like to be able to continue using everything that strict
offers, is there a 'safe' way to do this?

-- 
The T1 to Radvision is A.F.U. because of a glitch.
RedHat is watching IP theater.
:: http://www.s5h.net/ :: http://www.s5h.net/gpg
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From stephenca at ls26.net  Tue Nov 13 14:19:36 2007
From: stephenca at ls26.net (Stephen Cardie)
Date: Tue, 13 Nov 2007 22:19:36 +0000
Subject: [Thamesvalley-pm] perl subroutine refs
In-Reply-To: <20071113220543.62b81bcd@workstation>
References: <20071113220543.62b81bcd@workstation>
Message-ID: <473A22F8.1060808@ls26.net>



ed wrote:
> Hi,
>
> I'm trying to do something to compare scriptable plugin methods between
> php and perl, but I have a problem in that I cannot figure out how to
> do it with strict:
>
> #!/usr/bin/perl
>
> use warnings;
> use strict;
>
> my %subs;
>
> sub test {
> 	print( "Tested\n" );
> }
>
> my $l = "test";
>
> $subs{'plugname'} = &$l;
> $subs{'plugname'};
>
> The error message insists that this is not possible while using strict
> refs, but I'd like to be able to continue using everything that strict
> offers, is there a 'safe' way to do this?
>   

ed,

This won't work under strict() because you are attempting to create a 
symbolic reference (see perldoc perlref).  If you really, really want to 
do this, you need

no strict qw(refs);

But you don't want to do that ...

One "safe" way to do this is with a despatch table; basically, a hash of 
anonymous subs.

my(%despatch) = (
    test => sub { print "Tested\n" },
);

# later ...
my(%subs);
$subs{plugname} = 'test';
$despatch{$subs{plugname}}->();

# ...
__END__

Cheers,

Steve



From abw at wardley.org  Tue Nov 13 23:36:21 2007
From: abw at wardley.org (Andy Wardley)
Date: Wed, 14 Nov 2007 07:36:21 +0000
Subject: [Thamesvalley-pm] perl subroutine refs
In-Reply-To: <20071113220543.62b81bcd@workstation>
References: <20071113220543.62b81bcd@workstation>
Message-ID: <473AA575.30800@wardley.org>

ed wrote:
> $subs{'plugname'} = &$l;

   $subs{'plugname'} = \&test;

HTH
A