template::stash(3)
NAME
Template::Stash - Magical storage for template variables
SYNOPSIS
use Template::Stash; my $stash = Template::Stash->new(vars); # get variable values $value = $stash->get($variable); $value = $stash->get(@compound); # set variable value $stash->set($variable, $value); $stash->set(@compound, $value); # default variable value $stash->set($variable, $value, 1); $stash->set(@compound, $value, 1); # set variable values en masse $stash->update(new_vars) # methods for (de-)localising variables $stash = $stash->clone(new_vars); $stash = $stash->declone();
DESCRIPTION
The Template::Stash module defines an object class which
is used to store variable values for the runtime use of
the template processor. Variable values are stored inter
nally in a hash reference (which itself is blessed to cre
ate the object) and are accessible via the get() and set()
methods.
Variables may reference hash arrays, lists, subroutines
and objects as well as simple values. The stash automati
cally performs the right magic when dealing with vari
ables, calling code or object methods, indexing into
lists, hashes, etc.
The stash has clone() and declone() methods which are used
by the template processor to make temporary copies of the
stash for localising changes made to variables.
PUBLIC METHODS
new%(params)
- The new() constructor method creates and returns a refer
ence to a new Template::Stash object. - my $stash = Template::Stash->new();
- A hash reference may be passed to provide variables and
values which should be used to initialise the stash.
my $stash = Template::Stash->new({ var1 => 'value1',var2 => 'value2'});- get($variable)
- The get() method retrieves the variable named by the first
parameter.
$value = $stash->get('var1');- Dotted compound variables can be retrieved by specifying
the variable elements by reference to a list. Each node
in the variable occupies two entries in the list. The
first gives the name of the variable element, the second
is a reference to a list of arguments for that element, or
0 if none.
[% foo.bar(10).baz(20) %]- $stash->get([ 'foo', 0, 'bar', [ 10 ], 'baz', [ 20 ]);
- set($variable, $value, $default)
- The set() method sets the variable name in the first
parameter to the value specified in the second.
$stash->set('var1', 'value1');- If the third parameter evaluates to a true value, the
variable is set only if it did not have a true value
before.
$stash->set('var2', 'default_value', 1);- Dotted compound variables may be specified as per get()
above.
[% foo.bar = 30 %]- $stash->set([ 'foo', 0, 'bar', 0 ], 30);
- The magical variable 'IMPORT' can be specified whose cor
responding value should be a hash reference. The contents
of the hash array are copied (i.e. imported) into the cur
rent namespace.
# foo.bar = baz, foo.wiz = waz
$stash->set('foo', { 'bar' => 'baz', 'wiz' => 'waz'- });
- # import 'foo' into main namespace: foo = baz, wiz =
- waz
$stash->set('IMPORT', $stash->get('foo')); - clone%(params)
- The clone() method creates and returns a new Tem
plate::Stash object which represents a localised copy of
the parent stash. Variables can be freely updated in the
cloned stash and when declone() is called, the original stash is returned with all its members intact and in the
same state as they were before clone() was called. - For convenience, a hash of parameters may be passed into
clone() which is used to update any simple variable (i.e. those that don't contain any namespace elements like 'foo'
and 'bar' but not 'foo.bar') variables while cloning the
stash. For adding and updating complex variables, the
set() method should be used after calling clone(). This will correctly resolve and/or create any necessary
namespace hashes. - A cloned stash maintains a reference to the stash that it
was copied from in its '_PARENT' member. - declone()
- The declone() method returns the '_PARENT' reference and
can be used to restore the state of a stash as described
above.
AUTHOR
Andy Wardley <abw@andywardley.com>
<http://www.andywardley.com/|http://www.andywardley.com/>
VERSION
2.67, distributed as part of the Template Toolkit version
2.08, released on 30 July 2002.
COPYRIGHT
- Copyright (C) 1996-2002 Andy Wardley. All Rights Re
- served.
Copyright (C) 1998-2002 Canon Research Centre Europe - Ltd.
- This module is free software; you can redistribute it
and/or modify it under the same terms as Perl itself.
SEE ALSO
- Template, Template::Context