NAME
Object::Instant - make objects without the hassle of defining a class
first
SYNOPSIS
use Object::Instant;
my $object = object { name => 'Alice' };
if ($object->has_name) {
print $object->name, "\n";
}
DESCRIPTION
Object::Instant is designed to be an alternative to returning hashrefs
from functions and methods. It's similar to Object::Anon but doesn't do
anything special with references or overloading.
Functions
`object(\%data, \@keys)`
Returns a blessed object built from the given arrayref.
For each key in the list of keys, a getter (`name` in the SYNOPSIS)
and predicate (`has_name` in the SYNOPSIS) method are created.
Objects are read-only.
Note that Object::Instant does not make a clone of %data before
blessing it; it is blessed directly.
`object(\%data)`
If @keys is not supplied, Object::Instant will do this:
@keys = keys(%data);
If there are some keys that will not always be present in your data,
passing Object::Instant a full list of every possible key is strongly
recommended!
`make_class(\@keys)`
Just makes the class, but doesn't bless a hashref into it. Returns a
string which is the name of the class. If called repeatedly with the
same keys, will return the same class name.
The class won't have a `new` method; if you need to create objects,
just directly bless hashrefs into it.
It is possible to use this in an @ISA, though that's not really the
intention of Object::Instant.
package My::Class {
use Object::Instant qw(make_class);
our @ISA = make_class[qw/ foo bar baz /];
sub new {
my ($class, $data) = (shift, @_);
bless $data, $class;
}
sub foobar {
my ($self) = (shift);
$self->foo . $self->bar;
}
}
`make_class` is not exported by default.
Diagnostics
Ambiguous method %s is getter, not predicate
Given the following:
my $object = object {
name => 'Alice',
has_name => 1,
};
Object::Instant doesn't know if you want the `has_name` method to be a
getter for the "has_name" attribute, or a predicate for the "name"
attribute. The getter wins, but it will issue a warning.
Key %s would be bad method name, not generating methods
You've got a key with a name that cannot be called as a method. For
example:
my $alice = object { 'given name' => 'Alice' };
Perl methods cannot contain spaces, so Object::Instant refuses to create
the method and gives you a warning. (Technically it is possible to create
and call methods containing spaces, but it's fiddly.)
Usage %s(self)
The methods defined by Object::Instant expect to be invoked with a blessed
object and no other parameters.
my $alice = object { 'name' => 'Alice' };
$alice->name(1234); # error
This throws an exception rather than just printing a warning.
BUGS
Please report any bugs to
<http://rt.cpan.org/Dist/Display.html?Queue=Object-Instant>.
SEE ALSO
Object::Anon, Object::Result.
AUTHOR
Toby Inkster <tobyink@cpan.org>.
COPYRIGHT AND LICENCE
This software is copyright (c) 2020 by Toby Inkster.
This is free software; you can redistribute it and/or modify it under the
same terms as the Perl 5 programming language system itself.
DISCLAIMER OF WARRANTIES
THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED
WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.