Using the backward compatibility module
PrestaShop's module API has greatly improved between version 1.4 and version 1.5 of the software.
Because there is a huge ecosystem of modules that are being upgraded to support the 1.5 module API while many shops are still using PrestaShop 1.4, the developers of PrestaShop chose to build Backward Compatibility, a free module which is only available for PrestaShop 1.4, and makes it possible to make 1.5 modules work in PrestaShop 1.4.
Including this module makes it possible to develop a 1.4 module that using PrestaShop 1.5 standards.
The 1.5 API's Helpers (HelperForm, HelperView, etc.) are still not available in PrestaShop 1.4.
Therefore, the following declarations are not necessary anymore:
The information they provide is available through these calls:
Download and install
You can download the Backward Compatibility module for free on PrestaShop Addons: http://addons.prestashop.com/en/administration-tools-prestashop-modules/6222-backward-compatibility.html
Unzip the file and put it the
/modules folder of your installation of PrestaShop 1.4.
You can else get it directly from PrestaShop's repository: https://github.com/PrestaShop/PrestaShop-backward_compatibility
Just clone the project on your own repository, then copy the content of the folder to the root folder of the module.
You do not have to click "Install" on this module in PrestaShop's "Modules" administration.
It is useless the install the module in PrestaShop 1.5.
How to use the module
To properly us the module, you must first declare it in the module constructor method:
Once this is in place, you can call $this->backward and $this->backward_error in your module in order to pinpoint 1.5- or 1.4-specific code:
...or if you want to prevent code from being used under PrestaShop 1.4 as long as the Backward Compatibility module is not available: