The Exchange Project Preview Release 2.1 Coding Standards Practice

** THIS DOCUMENT IS A DRAFT **

In order to keep the source code sane, a standard has to be followed
in the practice. Everyone has their own coding style, which has
advantages and disadvantages to somebody elses style. This document
will force a unified way to write code, while at the same time
allow for modifications to be made, to provide an optimial standard.

A general note regarding PHP3 and PHP4 compatibilty, developers are
requried to test their changes under both environments. Code may work
in PHP4, but may not in PHP3, and vica-versa.

Read the PHP installation guide, on how to install both PHP3 and PHP4
together on the same server.

PHP3 Compatibility Issues
-------------------------
* Something that will be done once the template structure has been
  implemented, is to change all <? php start tags to <?php for proper
  compatibility.

* It is best to define the constants early before 'includes' are made,
  as these includes cannot access constants that are set after the
  file has been 'included'. For example,
  
  define('TEXT', 'This text is shown in the include file');
  include('include_file.php');

* Classes that are called without parameters should be called as

  new className;
  
  and not as
  
  new className();

* Do not use the short version of echo, this will not work under PHP3.
  Please get in the habit of writing
  
  <?php echo $variable; ?>

  instead of
  
  <?=$varaible;?>


General
-------

* TABs should not be used as a indentations. To indent, use 2 whitespaces


Function Structure
------------------

* All custom functions should start with tep_

  function tep_my_function($parameter, $optional = '') {
    global $HTTP_GET_VARS, $another_variable;
    
    <function code>
    
    return true;
  }


Class Structure
---------------
* Class names should be in this format -> myWorkingClass

  class myWorkingClass {
    var $variable;
    
// class constuctor
    function myWorkingClass() {
    
      <function code>
    
      return true;
    }

// class methods
    function do_something() {
    
      $this->variable = 'set';
      
      return tue;
    }
  }
  
  $class = new myWorkingClass;
  $class->do_something();