Is there any situation where the 'old' syntax is preferable or even required?

It is not required for hashrefs like this but obviously you can't use the normal arrow to dereference things where there are no components. So, if you have a scalar reference the only ways to dereference that are with a $$ or using postfix dereference. In such situations I much prefer the $$ for clarity. In fact I've just tried this example to illustrate and it won't even compile with the postfix deref line uncommented (error is $* is no longer supported as of Perl 5.30).

#!/usr/bin/env perl
use strict;
use warnings;
use feature 'say';

my $foo = 'some string';
my $ref = \$foo;
say "Deref with \$\$: $$ref";
# Uncomment next line for compilation error - why?
#say "Postfix deref: $ref->$*";

[download]

Perhaps someone who likes/uses postfix deref can explain where the compilation error comes from and how to fix it. As for me, I'm quite happy with $$ in these situations.

See also I use postfix dereferencing ... for various comments on how wonderful/terrible postfix dereferencing is.

🦛

In reply to Re^3: Reading session data by hippo
in thread Reading session data by PeterKaagman

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.