sub AUTOLOAD {
    my $_call = our $AUTOLOAD;
    $_call =~ s/.*:://;
    my $self = shift;
    my $param = shift;
    ...
    $self->{$_call} = $_param || return $self->{$_call};
}
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my $o = Foo->new(); #create new object
$o->Available_Param_List(["one", "two"]); #methods that should be avai
+lable to $o
$o->one('this will work ok');
$o->nope('this should print a warn on saying that nope is not availabl
+e for $o');
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The traditional message is

Can't locate object method "nope" via package "Foo" (perhaps you forgo
+t to load "Foo"?) at file.pl line 4.
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Why won't the following suffice?

Can't locate object method "nope" (perhaps you forgot to specify "nope
+" to Available_Param_List) at file.pl line 4.
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Chances are you won't be calling nope more than one time per line, so you'll know exactly which object is giving the error.

Use Carp's croak to make the message appear to originate from the calling line.

#!/usr/bin/perl

my $o = Foo->new();

$o->available_methods([ qw/one two/]);

$o->one("This will work\n");
$o->two("This will work as well\n");
$o->three("This won't work\n");

package Foo;
use Carp;

my %Objs;
sub new {
        my $self = {};
        $Objs{$self} = {};
        bless $self, shift;
}

sub available_methods {
        my($self,$methods_ref) = @_;
        $Objs{$self}{methods} = $methods_ref;
}

sub DESTROY {
        my $self = shift;
        delete $Objs{$self};
}

sub AUTOLOAD {
        my $_call = our $AUTOLOAD;
        $_call =~ s/.*:://;
        my $self = shift;
        my $param = shift;
        if(grep /$_call/,@{ $Objs{$self}{methods} }) {
                print $param;
        }
        else {
                carp("Couldn't execute $_call\n");
        }
}
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It's almost there. this is the output I've got: ~$ perl p.pl This will work This will work as well Couldn't execute three at p.pl line 9 And, what I want to achieve is to print (for example) which variable raised that warning. Something like this: Couldn't execute three on $o at p.pl line 9 Perhaps am I asking to much?

    my $param = shift;
    ...
    $self->{$_call} = $_param || return $self->{$_call};
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I assume $param and $_param were supposed to be the same. That's a little obfuscated, and doesn't allow setting parameters to false values. A more typical way to do it is:

    # (after shifting everything but param)
    if (@_) {
        return $self->{$_call} = shift;
    } else {
        return $self->{$_call};
    }
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