NAME

Class::Simple::Readonly::Cached - cache messages to an object

VERSION

Version 0.10

SYNOPSIS

A sub-class of Class::Simple which caches calls to read the status of an object that are otherwise expensive.

It is up to the caller to maintain the cache if the object comes out of sync with the cache, for example by changing its state.

You can use this class to create a caching layer to an object of any class that works on objects which doesn't change its state based on input:

use Class::Simple::Readonly::Cached;

my $obj = Class::Simple->new();
$obj->val('foo');
$obj = Class::Simple::Readonly::Cached->new(object => $obj, cache => {});
my $val = $obj->val();
print "$val\n";	# Prints "foo"

#... set $obj to be some other class which will take an argument 'a',
#	with a value 'b'

$val = $obj->val(a => 'b');

SUBROUTINES/METHODS

new

Creates a Class::Simple::Readonly::Cached object.

It takes one mandatory parameter: cache, which is either an object which understands clear(), get() and set() calls, such as an CHI object; or is a reference to a hash where the return values are to be stored.

It takes one optional argument: object, which is an object which is taken to be the object to be cached. If not given, an object of the class Class::Simple is instantiated and that is used.

use Gedcom;

my %hash;
my $person = Gedcom::Person->new();
# ...Set up some data
my $object = Class::Simple::Readonly::Cached(object => $person, cache => \%hash);
my $father1 = $object->father();	# Will call gedcom->father() to get the person's father
my $father2 = $object->father();	# Will retrieve the father from the cache without calling person->father()

Takes one optional argument: quiet, if you attempt to cache an object that is already cached, rather than create another copy you receive a warning and the previous cached copy is returned. The 'quiet' option, when non-zero, silences the warning.

object

Return the encapsulated object

state

Returns the state of the object

print Data::Dumper->new([$obj->state()])->Dump();

can

Returns if the embedded object can handle a message

isa

Returns if the embedded object is the given type of object

AUTHOR

Nigel Horne, <njh at bandsman.co.uk>

BUGS

Doesn't work with Memoize.

Please report any bugs or feature requests to https://github.com/nigelhorne/Class-Simple-Readonly-Cached/issues. I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.

SEE ALSO

Class::Simple, CHI

SUPPORT

You can find documentation for this module with the perldoc command.

perldoc Class::Simple::Readonly::Cached

You can also look for information at:

LICENSE AND COPYRIGHT

Author Nigel Horne: njh@bandsman.co.uk Copyright (C) 2019-2024 Nigel Horne

Usage is subject to licence terms. The licence terms of this software are as follows: Personal single user, single computer use: GPL2 All other users (including Commercial, Charity, Educational, Government) must apply in writing for a licence for use from Nigel Horne at the above e-mail.