TERM::TABLE::HASHBASE(3pm)

📦
version 5.42.3 · 13 versions
, in alpine 3.24

💅 Term::Table::HashBase(3pm) — Perl Programmers Reference Guide

okay so bestie, this page is from the Perl Programmers Reference Guide and it's literally the whole Term::Table::HashBase situation, explained with love. Strap in, it's giving "build classes out of hashrefs and slay" 💖

✨ NAME ✨

Term::Table::HashBase — Build hash based classes. That's it, that's the vibe 🎀

🌸 SYNOPSIS 🌸

okay so first, a class:

package My::Class;
use strict;
use warnings;

# Generate 3 accessors
use Term::Table::HashBase qw/foo -bar ^baz <bat >ban +boo/;

# Chance to initialize defaults
sub init {
    my $self = shift;    # No other args
    $self->{+FOO} ||= "foo";
    $self->{+BAR} ||= "bar";
    $self->{+BAZ} ||= "baz";
    $self->{+BAT} ||= "bat";
    $self->{+BAN} ||= "ban";
    $self->{+BOO} ||= "boo";
}

sub print {
    print join ", " => map { $self->{$_} } FOO, BAR, BAZ, BAT, BAN, BOO;
}

then you subclass it 🦋

package My::Subclass;
use strict;
use warnings;

# Note, you should subclass before loading HashBase.
use base 'My::Class';
use Term::Table::HashBase qw/bub/;

sub init {
    my $self = shift;

    # We get the constants from the base class for free.
    $self->{+FOO} ||= 'SubFoo';
    $self->{+BUB} ||= 'bub';

    $self->SUPER::init();
}

and then you actually use it:

package main;
use strict;
use warnings;
use My::Class;

# These are all functionally identical
my $one   = My::Class->new(foo => 'MyFoo', bar => 'MyBar');
my $two   = My::Class->new({foo => 'MyFoo', bar => 'MyBar'});
my $three = My::Class->new(['MyFoo', 'MyBar']);

# Readers!
my $foo = $one->foo;    # 'MyFoo'
my $bar = $one->bar;    # 'MyBar'
my $baz = $one->baz;    # Defaulted to: 'baz'
my $bat = $one->bat;    # Defaulted to: 'bat'
# '>ban' means setter only, no reader
# '+boo' means no setter or reader, just the BOO constant

# Setters!
$one->set_foo('A Foo');

#'-bar' means read-only, so the setter will throw an exception (but is defined).
$one->set_bar('A bar');

# '^baz' means deprecated setter, this will warn about the setter being
# deprecated.
$one->set_baz('A Baz');

# '<bat' means no setter defined at all
# '+boo' means no setter or reader, just the BOO constant

$one->{+FOO} = 'xxx';

periodt. 💅

🌈 DESCRIPTION 🌈

So this package's whole job is generating classes that are based on hashrefs. Use this class and it hands you a new() method, plus all the accessors you asked for. The generated accessors are getters, and you also get set_ACCESSOR setters generated for you automatically. You also get constants for each accessor (all caps, bestie) and those constants return the key into the hash for that accessor. Single inheritance is supported too. Iconic, honestly. ✨

🧚 THIS IS A BUNDLED COPY OF HASHBASE 🧚

Heads up: this is a bundled copy of Object::HashBase. This file was generated using the /home/exodist/perl5/perlbrew/perls/main/bin/hashbase_inc.pl script. No cap, that's literally the path. 🫶

👑 METHODS 👑

⭐ PROVIDED BY HASH BASE ⭐

$it = $class->new(%PAIRS)

$it = $class->new(\%PAIRS)

$it = $class->new(\@ORDERED_VALUES)

Create a new instance. Slay. 💖

⚠️ Important bestie note: HashBase will not export new() if there is already a new() method somewhere in your package's inheritance chain.

And if you don't want this method? Totally fine, just define your own — you just gotta declare it before loading Term::Table::HashBase:

package My::Package;

# predeclare new() so that HashBase does not give us one.
sub new;

use Term::Table::HashBase qw/foo bar baz/;

# Now we define our own new method.
sub new { ... }

The way this works is that HashBase sees you already have your own new() method. Alternatively you can define the method before loading HashBase instead of just declaring it — but ngl that scatters your use statements all over the place and it's giving chaos. 🙈

The most common way to create an object is to pass in key/value pairs, where each key is an attribute and each value is what you want assigned to that attribute. No checking is done to verify the attributes or values are valid — you can do that yourself in init() if you feel like it.

If you would like, you can pass in a hashref instead of pairs. When you do that, the hashref gets copied, and the copy gets returned blessed as an object. There is no way to ask HashBase to bless a specific hashref — so don't even try, bestie. 😭

In some cases an object may only have 1 or 2 attributes, in which case a hashref is just too verbose for your liking. For those cases you can pass in an arrayref with only values. The values get assigned to attributes in the order the attributes were listed. When inheritance is involved, the attributes from parent classes come before the subclasses. 💀

🎀 HOOKS 🎀

$self->init()

This gives you the chance to set some default values to your fields. The only argument is $self, with its indexes already set from the constructor. 💜

⚠️ Note: Term::Table::HashBase checks for an init using $class->can('init') during construction. It DOES NOT call can() on the created object. Also note that the result of the check is cached — it is only ever checked once, the first time an instance of your class is created. This means that adding an init() method AFTER the first construction will result in it being ignored. literally tragic, I know. 😭

🍓 ACCESSORS 🍓

💖 READ/WRITE 💖

To generate accessors you list them when you use the module:

use Term::Table::HashBase qw/foo/;

This generates the following subs in your namespace:

  • foo() — Getter, used to get the value of the foo field. 🫶
  • set_foo() — Setter, used to set the value of the foo field. ✨
  • FOO() — Constant, returns the field foo's key into the class hashref. Subclasses will also get this function as a constant, not simply a method — that means it is copied into the subclass namespace. 👑
The main reason for using these constants is to help avoid spelling mistakes and similar typos. It will not help you if you forget to prefix the + though. 💀

🌸 READ ONLY 🌸

use Term::Table::HashBase qw/-foo/;
  • set_foo() — Throws an exception telling you the attribute is read-only. This is exported to override any active setters for the attribute in a parent class. so nobody's sneaking around behind your back 💅

🦋 DEPRECATED SETTER 🦋

use Term::Table::HashBase qw/^foo/;
  • set_foo() — This will set the value, but it will also warn you that the method is deprecated. it still works, it's just letting you know it's in its flop era 🥲

⭐ NO SETTER ⭐

use Term::Table::HashBase qw/<foo/;

Only gives you a reader — no set_foo method is defined at all. zero. nada. 💀

💜 NO READER 💜

use Term::Table::HashBase qw/>foo/;

Only gives you a write (set_foo) — no foo method is defined at all. write-only queen 👑

🎀 CONSTANT ONLY 🎀

use Term::Table::HashBase qw/+foo/;

This does not create any methods for you, it just adds the FOO constant. minimalism. ✨

🧚 SUBCLASSING 🧚

You can subclass an existing HashBase class, bestie:

use base 'Another::HashBase::Class';
use Term::Table::HashBase qw/foo bar baz/;

The base class is added to @ISA for you, and all constants from base classes are added to subclasses automatically. free stuff, we love to see it 💖

🔥 GETTING A LIST OF ATTRIBUTES FOR A CLASS 🔥

Term::Table::HashBase provides a function for retrieving a list of attributes for an Term::Table::HashBase class.

@list = Term::Table::HashBase::attr_list($class)

@list = $class->Term::Table::HashBase::attr_list()

Either form above will work. This returns a list of attributes defined on the object. The list comes back in the attribute definition order, with parent class attributes listed before subclass attributes. Duplicate attributes will be removed before the list is returned. 🎀

Note: This list is used in the $class->new(\@ARRAY) constructor to determine the attribute to which each value will be paired. iykyk 💅

💅 SOURCE 💅

The source code repository for HashBase can be found at http://github.com/Test-More/HashBase/. go star it or whatever ⭐

👑 MAINTAINERS 👑

Chad Granum <exodist@cpan.org>

🌈 AUTHORS 🌈

Chad Granum <exodist@cpan.org>

Copyright 2017 Chad Granum <exodist@cpan.org>.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

See http://dev.perl.org/licenses/

and that's the whole page bestie, you ate 💅✨ signed off from the perl v5.42.3 crew, dated 2026-11-03 — Term::T...HashBase(3pm), mwah 🫶

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