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Comment by mannykannot | Hacker News Reader

I still use Perl 5 for some tasks, but my rule-of-thumb is that if I anticipate wanting to use references, I will go elsewhere.

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I suggest and use the opposite rule of thumb, "always use references". It tends to simplify things. Python writes the same rule into the language itself.

When I used it for larger tasks, I did the same. Nowadays, the consequence of my rule is that Perl 5 sits in my toolbox between Awk and Python.

> but my rule-of-thumb is that if I anticipate wanting to use references, I will go elsewhere

Why? References are not scary and they work just like in any other language -- they are simply a memory address that points to another value stored somewhere else.

The implementation is not the issue; it is the awkward and fussy syntax. It is not a show-stopper -- I coped with it for a while -- but there are better alternatives.

The happy-path syntax is pretty straightforward. I wonder if you're under the impression like some that you need to use the arrow syntax or prefixing dollar for every reference, and not just the first? That's not the case. e.g.

    my @a = (
      { first=>1, second=>"b", another_ref=>["y"] },
      { first=>1, second=>"b", another_ref=>["z"] },
    );

    say $a[0]{first}; # Outputs 1
    say $a[1]{another_ref}[0]; # Outputs z
    
    my $a2 = \@a; # top level is a reference too now
    say $a2->[1]{another_ref}[0]; # Outputs 1, arrow only needed at top level
    
    # The following are alternate syntax that I find unnecessary and better left alone (and most do)
    say $a2->[1]->{another_ref}->[0]; # Outputs 1, explicit, entirely unneeded because it's unambiguous without extra arrows
    say $$a2[1]{another_ref}[0]; # Outputs 1, extra prefixing $ dereferences first level ref

Personally, I'm happy with a single arrow that lets me know if I have a reference or not. References are important, because they denote that this data may be accessed elsewhere as well, so I'm happy to have a small reminder. Inner level references needing a bit of care if they are copied is somewhat normal though, most non-toy languages have some concept of deep or shallow copying.

I rest my case (it is a personal preference, anyway.)

Fair enough. I did go a little overboard in the name of completeness. IT just boils down to actually understanding what a reference is in Perl (which is something that needs to be done for anything non-amateur), and then realizing there's one -> or not depending on if it's a reference (and doing the wrong thing will fail, not do weird stuff).

Personally, I like that it forces you to be aware that this data structure is likely in use somewhere else as well, and your changes may not be local (which is true of deeper levels regardless).

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