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README.md

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 # RRULE for PHP
 
-work in progress
+Lightweight and fast implementation of recurrence rules for PHP (RFC 5545).
+
+[![Build Status](https://travis-ci.org/rlanvin/php-rrule.svg?branch=master)](https://travis-ci.org/rlanvin/php-rrule)
+
+## Basic example
+
+```php
+use RRule\RRule;
+
+$rrule = new RRule([
+	'FREQ' => 'MONTHLY',
+	'INTERVAL' => 1,
+	'DTSTART' => '2015-06-01',
+	'COUNT' => 6
+]);
+
+foreach ( $rrule as $occurrence ) {
+	echo $occurrence->format('D d M Y'),"\n";
+}
+
+// will output:
+// Mon 01 Jun 2015
+// Wed 01 Jul 2015
+// Sat 01 Aug 2015
+// Tue 01 Sep 2015
+// Thu 01 Oct 2015
+// Sun 01 Nov 2015
+```
+
+Complete doc is available in [the wiki](https://github.com/rlanvin/php-rrule/wiki).
+
+## Requirements
+
+- PHP >= 5.4
+
+## Installation
+
+This is still a work in progress, use at your own risk!
+In particular, HOURLY, MINUTELY and SECONDELY frequencies are not implemented.
+
+The recommended way is to install the lib [through Composer](http://getcomposer.org/).
+
+Just add this to your `composer.json` file:
+
+```JSON
+{
+    "require": {
+        "rlanvin/php-rrule": "dev-master*"
+    }
+}
+```
+
+Then run `composer install` or `composer update`.
+
+Now you can use the autoloader, and you will have access to the library:
+
+```php
+<?php
+require 'vendor/autoload.php';
+```
+
+### Alternative method
+
+You can download `src/RRule.php` and require it.
+
+## Note
+
+I started this library because I wasn't happy with the existing implementations
+in PHP. The ones I tested were slow and/or had a very awkward/verbose API that
+I didn't like to use. They were also all missing a generator/iterator, which I
+think is key. So I thought it would be a good learning project to port the
+Python dateutil/rrule.py class into PHP.
+
+The Python lib was a bit difficult to understand at first. The algorithms
+used are very smart (and fast), but they not commented and the variables are
+very opaque (I'm looking at you `lno1wkst`). I tried to comment and
+explain most of the algorithm in this PHP port, so feel free to check the code.
+
+The lib differs from the python version in various aspects, notably in the 
+respect of the RFC. This version is strictier and will not accept many
+non-compliant combinations of rule parts, that the python version otherwise accepts.
+There are also some additional features in this version.
+
+## Documentation
+
+Complete doc is available in [the wiki](https://github.com/rlanvin/php-rrule/wiki).
+
+## License
+
+This library is released under the MIT License.