Class naming and the exp prefix #

This page is for PHP developers who add classes, functions, settings or tables. Names in Exponential follow a few rules that keep thousands of classes from colliding in one class map, and that keep existing extensions working. The canonical statement is Naming prefixes: sevenx and exp.

Contents #

1. The rules in one table
2. Your prefix
3. exp and sevenx
4. Kernel eZ identifiers stay
5. Files and class names
6. Namespaced classes
7. Other identifiers

The rules in one table #

Your prefix #

All classes share one class map, so two classes with the same name in two extensions break each other: the generator warns about a duplicate, and one of them wins. Start every class, function, template operator, fetch function, setting block and table of your extension with a prefix that is yours: acmeReportService, acme_report (table), acmereport_total (operator), [AcmeReportSettings] (block).

exp and sevenx #

• exp is the project's prefix. New code in the kernel and in project extensions uses it: explayouts, expai, expqueue, expHelpAudience, the exp: console commands. Use exp only for code you contribute to the project.
• sevenx is 7x's official public PHP code prefix; "7x" cannot be one, because a PHP identifier cannot start with a digit (class 7xFoo is a parse error).
• Existing sevenx_* and exp* names are not renamed to make the prefixes look uniform; the folder name of an extension is its identity in settings.

Kernel eZ identifiers stay #

eZContentObject, eZINI, eZDB, eZPersistentObject, ezpKernelWeb, the ez* file names, module names, template operators, settings and database tables are real identifiers. They are never renamed: renaming would break every extension and template written for them. eZ is the prefix of those identifiers, not the name of the product.

Two consequences for your code:

• Do not create new classes with an eZ or ezp prefix; they look like kernel classes and may collide with future ones.
• In comments, messages and documentation the product is Exponential. The old product name appears only as past history; a class name such as eZContentObject is not the product name and stays as it is.

Files and class names #

The class map generator finds classes by scanning files, so a class in a file of another name is found too; the rule is for people, who look for acmereportservice.php when they read acmeReportService.

Namespaced classes #

The kernel uses namespaces only for the runnable classes (commands, cronjob parts, module views) and their services:

Everything else is global, prefixed class names (Module views as classes).

Other identifiers #

• INI files and blocks: your own file (acmereport.ini) with your own blocks; changes to kernel files go into *.ini.append.php of your extension.
• Tables: acme_*, lower case, unquoted names that work on every supported database (Code for every supported database).
• Template operators and fetch functions: prefixed (acmereport_money, fetch( 'acmereport', 'items' )).
• Translation contexts: extension/acmereport.
• CSS classes and JavaScript globals: your prefix as well.

Related pages #

• Layering and naming
• Autoloads and class maps
• Naming and branding during an upgrade
• Free documentation: this page is free to copy, translate and improve under the GNU FDL 1.3.