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=== Flower -- Petal for Perl 6

NOTE: A massive rewrite is planned for Flower that will vastly change how
      it works, and what it's capable of. When it's done, Flower will be
      a LOT more than what it is now. See docs/TODO.txt for more details.

Petal is the Perl Template Attribute Language (Perl 5), and is derived from the 
TAL, METAL and TALES specifications from Zope (Python).

Flower is an implementation of Petal in Perl 6.

It's not the same as the Perl 5 implementation, and has a different
feature-set and parsing model.

That said, it tries to implement as much of Petal as possible in a mostly
compatible form, major differences are listed below.

Status: Flower is currently usable, but there are still plenty of planned
        features. See the docs/TODO.txt for a list of things I'm planning.

= Requirements:

 - Exemel, the XML library that powers Flower.

= Optional libraries:

 - Temporal-Utils, needed if you want to use Flower::Utils::Date

= Major Differences from Petal:

 * The default local namespace is 'tal', and to override it, you must
   declare instead of the Petal namespace.
 * Flower can use template strings instead of requiring files.
 * Flower does not support the multiple template files based on language.
 * Adding custom modifiers is completely different in Flower.
 * There is NO support for anything but well-formed XML.
   There is no equivelant to the Petal::Parser::HTB, and no plans for one.
   Use well-formed XML, it's just better.
 * Flower supports petal:block elements, as per the PHPTAL project.
 * While you can use the 'structure' keyword, it's not really needed.
   If you want an unescaped XML structure for a replacement, send an
   Exemel object (any class other than Document) and it will be added to
   the XML tree. Send an array of Exemel objects, and they will additionally
   be parsed for TAL statements.
 * Nested repeats cannot use the same attribute name, it will get clobbered.
 * The built-in repeat object is implemented as per the Zope/PHPTAL, not
   the Petal version. Note: it does not support the 'letter' or 'Letter' 
   attributes, but instead has some new methods that take paramters: 
     'every xx'   the number (not the index) is divisible by xx.
     'skip xx'    the number is not divisible by xx.
     'gt xx'      the number is greater than xx.
     'lt xx'      the number is less than xx.
     'eq xx'      the number is equal to xx.
     'ne xx'      the number is not equal to xx.
 * I'm not sure how Petal, PHPTAL or Zope deal with TAL attributes in the
   root element (the top-most element of the document), but to avoid death,
   destruction and mayhem, Flower only processes 'define', 'attributes'
   and 'content' tags on the root element. The rest of the tags are only
   processed on children of the root.

The above list will be updated as this project is developed, as I'm sure
other changes will be introduced that will be a gotchya for users of Petal,
Zope or PHPTAL.

= Flower::Utils

Inspired by Petal::Utils, Flower includes a namespace called Flower::Utils::
If you load modules in the Petal::Utils:: namespace, it will add additional
modifiers. The following sets are currently included with Flower:

  - Text, same as the :text set from Petal::Utils
    lc:      make the string lowercase.
    uc:      make the string uppercase.
    ucfirst: make the first letter of the string uppercase.
    substr:  extract a portion of the string.
    printf:  format a string or object in a specified way.
  - List, similar to the :list set from Petal::Utils.
    group:   turns a flat Array into a nested Array, where each inner 
             Array has a set number of elements in it.
    sort:    sort the array using the default sort algorithm.
    limit:   only return the first number of items from the list.
    shuffle: shuffle the list into a random order.
    pick:    pick a set number of items randomly from the list.
    reverse: reverse the contents of the list.
  - Date, similar to the :date set from Petal::Utils, using on DateTime::Utils
    date:     Builds a DateTime object using specified paramters.
    time:     Builds a DateTime object from a Unix epoch.
    strftime: Displays a date/time string in a specified format.
    rfc:      A modifier specifically for use with strftime, as the format.
    now:      A modifier specifically for use with strftime, as the object.
  - Perl, makes a 'perl:' modifier available, which is the counterpart
    to Zope's 'python:' or PHPTAL's 'php:' modifiers.
    There are some extra, more dangerous modifiers included, but they
    are not exported by default, and must be imported manually.
  - Debug, similar to :debug set from Petal::Utils.
    dump: modifier spits out the .perl representation of the object.
    what: modifier spits out the class name of the object.

In addition, the following sets are planned for inclusion very soon:

  - Logic, similar to the :logic set from Petal::Utils
  - Hash, same as the :hash set from Petal::Utils

The syntax for the Flower::Utils methods is based on the modifiers from
Petal::Utils, but extended to use the Flower-specific extensions (the
same method that is used to parse method call parameters in queries.)
As is obvious, the syntax is not always the same, and not all of the
modifiers are the same.

Full documentation for the usage of Flower and the Flower::Utils modifiers
will be included in the docs/ folder in an upcoming release, until then
there are comments in the libraries, and test files in t/ that show the
proper usage.

The URI set from Petal::Utils is not planned for inclusion,
feel free to write it if you need it.
I'm sure new exciting libraries will be made adding onto these.

= Author: Timothy Totten
= License: Artistic License 2.0

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