All package names are written in UpperCamelCase. In order to avoid problems with different filesystems, only the characters a-z, A-Z and 0-9 are allowed for package names – don't use special characters.

Only the characters a-z, A-Z and 0-9 are allowed for class names – don't use special characters. The underscore sign "_" is allowed for separating the package name from the sub-package or component name from the sub-component name and so on.

All class names are written in UpperCamelCase, all uppercase names are allowed for well established abbreviations. Class names must be nouns, never adjectives.

A class name must start with the prefix "F3_". The name of the package containing the class follows, parts of the package hierarchy are seperated with underscores.

The name of abstract classes should start with the word "Abstract".

A few examples follow:

Only the characters a-z, A-Z and 0-9 are allowed for interface names – don't use special characters. The underscore sign "_" is allowed for separating the package name from the interface name from the sub-component name and so on.

All interface names are written in UpperCamelCase, all uppercase names are allowed for well established abbreviations. Interface names must be adjectives or nouns and have the Interface suffix.

An interface name must start with the prefix "F3_". The name of the package containing the interface follows, parts of the package hierarchy are seperated with underscores. A few examples follow:

Exception naming basically follows the rules for naming classes. There are two possible types of exceptions: Generic exceptions and specific exceptions. Generic exceptions should be named "Exception" preceeded by their namespace. Specific exceptions should reside in their own sub-namespace and must not contain the word Exception.

All method names are written in lowerCamelCase, all uppercase names are allowed for well established abbreviations. In order to avoid problems with different filesystems, only the characters a-z, A-Z and 0-9 are allowed for method names – don't use special characters.

Make method names descriptive, but keep them concise at the same time. Constructors must always be called __construct(), never use the class name as a method name.

A few examples:

Variable names are written in lowerCamelCase and should be

The following example shows two variables with the same meaning but different naming. You'll surely agree the longer versions are better (don't you ...?).

As a special exception you may use variable names like $i, $j and $k for numeric indexes in for loops if it's clear what they mean on the first sight. But even then you might want to avoid them.

All constant names are written in UPPERCASE. This includes TRUE, FALSE and NULL. Words can be separated by underscores - you can also use the underscore to group constants thematically:

It is, by the way, a good idea to use constants for defining regular expression patterns (as seen above) instead of defining them somewhere in your code.

The directory layout used for FLOW3 is shown below. Conventions for file names will be explained in it's own section below.

In addition to the directory naming rules laid out above there are also rules for naming the files inside those directories, of course. Here we go:

Here are some examples:

In general, we use single quotes to enclose literal strings:

$vision = 'Inspiring people to share';

If the string itself contains single quotes or apostrophes, we use double quotes:

$message = "'Kasper' is the name of the friendly ghost.";

If you'd like to insert values from variables, we recommend to concatenate strings or use double quotes in the following form:

$message = 'Hey ' . $name . ', you look ' . $look . ' today!';
$message = "Hey $name, you look $look today!";

As you've seen in the previous example, we concatenate strings by using the dot operator. A space must be inserted before and after the dot for better readability:

$vision = 'Inspiring people ' . 'to share.';

You may break a string into multiple lines if you use the dot operator. You'll have to indent each following line to mark them as part of the value assignment:

$vision = 'Inspiring' .
   'people ' .
   'to ' .
   'share';

...

class F3_MyPackage_MyComponent {

}