Zen Cart® Coding Standards
Currently the Zen Cart® Team is using a mix of the pear/phpBB coding standards docs to provide the categories as below.
The coding standards posted here are what we strive for. They are not a definition of how code is currently written. So, if the code you get does not match posted standards, don't be surprised. It's a long and arduous battle to convert all core code.
Currently, the standard is not to use hard tabs, and to use two spaces per indent.
The Zen Cart® Team's thoughts are that regardless of whether you use tabs or spaces for indents, anything more than two spaces can quickly lead to indent chaos. The argument then becomes whether indents should be hard tabs or soft spaces.
Soft spaces are preferred, unless someone can come up with a convincing argument otherwise (mainly because the tab /t can be interpreted differently across OS's and editors, whereas a space is always interpreted the same).
PHP Code Tags
Never use short open tags <? or asp tags <%; always use the full <?php ?> tags.