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> I don't miss perls halfarsed function args.

You mean you don't like writing things like...

    sub foo {
        my ($a, $b, $c) = shift;

?

KaiserPro a day ago [ - ]

Indeed!

It just grinds my gears that _I_ need to check to see if the caller has given me all the required bits. That seems like something the language should do.

I understand that it does give you a lot of flexibility, but Hnnnnnnnnn

(from what I recall object oriented perl doesn't give you this flexibility, but I'm not sure, as I never really did it. )

jstanley a day ago [ - ]

Object oriented perl gives you exactly the same flexibility.

If you have a module called "My::Module", and you call "My::Module->some_method", then you'd implement that like:

    sub some_method {
        my ($pkg, @args) = @_;

i.e. the module gets passed (as a string) as the first argument. You can then call

    $pkg->some_other_method;

And similarly, if you have an object "$foo" you would call it like "$foo->some_other_method" and implement it as:

    sub some_method {
        my ($self, @args) = @_;

i.e. the object gets passed as the first argument. And you can call "$self->some_other_method" with it.

A minimal class is just:

    package My::Module;

    sub new {
        my ($pkg, %opts) = @_;

        my $self = bless \%opts, $pkg;

        return $self;
    }

    1;

Don't let them tell you you need Moo or Moose or Mouse or fields.pm. Hand-rolled objects is the way :)

oneshtein 2 days ago [ - ]

  Yes, I hate to write

  sub foo($$$) {
    my ($a, $b, $c) = @_;
  }

Where @_ is array of arguments, and ($$$) is function prototype (3 scalars are expected).

AndrewDavis 2 days ago [ - ]

Perl has subroutine signatures now. You can write

sub foo ($x, $y, $x) { ...}

It's just syntactic sugar, so you still can't pass in multiple lists, and the list must be the final parameter.

a day ago [ - ]

[deleted]

AndrewDavis 2 days ago [ - ]

Not sure if you've deliberately put in two bugs there haha

1. shift only shifts off the first element.

2. (if classify this as a bug) using $a and $b are frowned upon because they're the default variables when using sort.

7952 2 days ago [ - ]

Oh wow I had forgotten about default variables. Such a lovely and inscrutable idea.

jstanley 2 days ago [ - ]

Ha, (1.) was deliberate but I'd forgotten (2.)

sshine 2 days ago [ - ]

Yeah, you probably want

  my ($x, $y, $z) = @shift;

:-D

rurban a day ago [ - ]

For reference:

Valid is either

   sub () {
     my ($x, $y, $z) = @_;

   sub ($x, $y, $z) {

sshine a day ago [ - ]

I should have said

  my ($x, $y, $z) = @$_[0];

but I was making a joke.

If $_[0] is an array reference, @$_[0] becomes a list.

The joke was a reference to most wrong Perl programs being valid for something.

Hence the meme: "93% of Paint Splatters are Valid Perl Programs"

https://www.mcmillen.dev/sigbovik/

kqr a day ago [ - ]

Why the empty prototype in the first alternative?

rurban a day ago [ - ]

yeah, you could leave that out, but then I have to invent a name

kqr a day ago [ - ]

Really? Anonymous subroutines/coderefs are defined with sub {} are they not?