NAME
Template::Plugin::StringTree - Access tree-like groups of strings
naturally in code and Templates
SYNOPSIS
use Template::Plugin::StringTree;
# Create a StringTree and set some values
my $Tree = Template::Plugin::StringTree->new;
$Tree->set('foo', 'one');
$Tree->set('foo.bar', 'two');
$Tree->set('you.get.the.point' => 'right?');
# Get simple hash of these variables for the template
my $vars = $Tree->variables;
#######################################################
# Later that night in a Template
After the number [% foo %] comes the number [% foo.bar %], [% you.get.the.point %]
#######################################################
# Which of course produces
After the number one comes the number two, right?
DESCRIPTION
For a couple of months, I had found it really annoying that when I
wanted to put a bunch of configuration options into a template, that I
couldn't use a natural [% IF show.pictures %][% IF
show.pictures.dropshadow %] ...etc... type of notation. Simply, to get
"dot" formatting in template, you need hashes. Which means stupid
notation like [% show.pictures.at_all %]. ugh...
As the size of the config tree I wanted to use grew and grew, it finally
started getting totally out of control, so I've created
Template::Plugin::StringTree, which lets you build tree structures in
which every node can have a value. And you can get at these naturally in
templates.
METHODS
new
The "new" constructor simply creates a new ::StringTree object and
returns it.
get $path
Taking a single "this.is.a.path" argument, the "get" method returns the
value associated with the path, if there is one.
Returns the value for the path, if one exists. Returns "undef" if no
value exists at that path.
set $path, $value
The "set" method takes a "this.is.a.path" style path and a value for
that path. "undef" is valid as a value, erasing a single value at the
node for the path. ( It does not remove children of that node ).
Returns true if the value is set correctly, or "undef" on error.
The "add" method is nearly identical to the normal "set" method, except
that the it expects there NOT to be an existing value in place. Rather
than overwrite an existing value, this method will return an error.
Returns true if there is no existing value, and it is successfully set,
or "undef" if there is an existing value, or an error while setting.
hash
The "hash" method produces a flat hash equivalent to the
Template::Plugin::StringTree object, which can be passed to the template
parser. You can manually add additional elements to the hash after it
has been produced, but you should not attempt to add anything to a hash
key the same as the first element in a path already added via the "set"
method earlier.
Returns a reference to a HASH containing the tree of strings.
freeze
Ever good structure can be serialized and deserialized, and this one is
no exception. The "freeze" method takes a ::StringTree object and
converts it into a string, which just so happens to be highly useful as
a config file format!
foo: one
foo.bar: two
you.get.the.point: right?
So terribly simple. To make life just a LITTLE more complicated though,
Template::Plugin::StringTree does a little bit of escaping if there's a
newline in the string. But since you'll probably never DO that, it won't
be a problem will it? :)
thaw $string
The "thaw" method is the reverse of the "freeze" method, taking the same
format string turning it back into a Template::Plugin::StringTree
object. THIS is where using this module as a config file -> template
mechanism really comes into it's own. Each entry is the config file is
available using the same path in Template Toolkit templates.
Template::Plugin::StringTree takes care of all the details or making it
work across the different models transparently.
If the string is formatted correctly, returns a new
Template::Plugin::StringTree object. Returns "undef" on error, probably
because the string wasn't formatted correctly.
equal $path, $value
The "equal" method provides a quick and convenient bit of shorthand to
let you see if a particular path equals a particular value. And the
method is totally undef-safe. You can test for a value of "undef", and
test a value against a path which returns "undef" quite safely.
Returns true if the value matches the path, or false otherwise.
SUPPORT
Bugs should be submitted via the CPAN bug tracker, located at
http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Template%3A%3APlugin%3A%3AStringTree
For other issues, contact the author
AUTHOR
Adam Kennedy (Maintainer)
[email protected]
http//ali.as/
COPYRIGHT
Copyright (c) 2004 Adam Kennedy. All rights reserved. This program is
free software; you can redistribute it and/or modify it under the same
terms as Perl itself.
The full text of the license can be found in the LICENSE file included
with this module.
