I do use 5.022 so I have a sufficiently modern version of Perl, though I admit I prefer the old notation choroba used, probably because I'm not very Object Oriented minded (though I admit yours is easier to read at a glance tybalt89). That said, I tried it, and it worked exactly the same, but it gave me the following warning along the way (not sure why).

Array found where operator expected at Web_Chat_IP_Match.pl line 141, 
+near "->@"

        (Missing operator before @?)
[download]

I've noticed that different people prefer different ways when doing things like this: &{}, %{}, @{}, ${} vs. &$, %$, @$, $$ vs. ->{} and ->[].

I've sensed rumblings of a past holy war, or at least a past split in the clergy that lead to the Perl programmer equivalents of Lutheranism or Protestantism in some of the things I've read about it.

Hi perldigious,

tybalt89's suggestion appears to be Postfix Reference Slicing, which is part of the new Postfix Dereference Syntax, which says:

In Perl 5.20 and 5.22, this syntax must be enabled with use feature 'postderef'. As of Perl 5.24, no feature declarations are required to make it available.

Hope this helps,
-- Hauke D

That does help, thanks haukex. That use feature 'postderef'; reduced the warning to:

Postfix dereference is experimental at Web_Chat_IP_Match.pl line 142.

So "sufficiently modern" really meant "the most recent version" then. :-)

I'll probably stick to the old block notation anyway, at least for the near foreseeable future. I'm just more comfortable with it I guess.

I love it when things get difficult; after all, difficult pays the mortgage. - Dr. Keith Whites
I hate it when things get difficult, so I'll just sell my house and rent cheap instead. - perldigious

G'day perldigious,

This is to address a number of points in this branch of the thread; in particular, versions, features, warnings and interpolating postfix dereferencing within strings.

Firstly, starting with v5.24:

$ perl -v | head -2 | tail -1
This is perl 5, version 24, subversion 0 (v5.24.0) built for darwin-th
+read-multi-2level
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This code recognises postderef syntax outside of strings but not within strings:

#!/usr/bin/env perl -l

use strict;
use warnings;

my $x = [qw{test string}];

print $x->@*;
print "$x->@*";
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Output:

teststring
ARRAY(0x7fc63c005498)->@*
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Adding either of these:

use 5.024;
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or

use feature qw{postderef_qq};
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Allows interpolation within strings:

Output:

teststring
test string
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Now looking at v5.20.

$ perl -v | head -2 | tail -1
This is perl 5, version 20, subversion 0 (v5.20.0) built for darwin-th
+read-multi-2level
[download]

Output using the same initial code as before:

Array found where operator expected at ./pm_1174734_postderef.pl line 
+11, at end of line
    (Missing operator before ?)
syntax error at ./pm_1174734_postderef.pl line 11, near "->@*"
Execution of ./pm_1174734_postderef.pl aborted due to compilation erro
+rs.
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To make this work, you need to turn off the experimental warnings (after the use warnings line) and use both the postderef and the postderef_qq features.

use warnings;
no warnings qw{experimental::postderef};
use feature qw{postderef postderef_qq};
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Using the code and version shown, this outputs:

teststring
test string
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Specifying a minimum version in the code, but running with a lesser version, gives:

Perl v5.20.0 required--this is only v5.18.0, stopped at ...
BEGIN failed--compilation aborted at ...
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This tells you how to fix but not why.

Not specifying the version, gives:

Unknown warnings category 'experimental::postderef' at ...
BEGIN failed--compilation aborted at ...
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This provides the why but not the how (i.e. you'll need some research to determine if that's a valid category and, if so, at what version it was introduced).

I prefer to specify the version. You may have a different preference or, perhaps, might be guided by in-house coding standards.

See also:

• perl5200delta: Experimental Postfix Dereferencing
• perldelta: Postfix dereferencing is no longer experimental [Correct at time of writing; current stable version 5.24; will refer to a different delta in future versions.]
• perl52400delta: Postfix dereferencing is no longer experimental [Dead link at time of writing; current stable version 5.24; expected to be a valid link in future versions.]
• use; feature; perlexperiment.
• CPAN pragma: experimental
• CPAN pragma: experimentals

Updates:

• change of meaning: s{expected to be a dead link}{will refer to a different delta}
• additional doco: Added manpage names to links: perldelta & perl52400delta

— Ken