Aspects can declare attributes, methods, constants and constructors that are owned by other types. These are called inter-type declarations.
Example 8.1: Attribute introduction
<?php
//Declare $pearLog and $debug attributes in all types prefixed by Bo.
private Bo*::$pearLog, Bo*::$debug=false;
//Declare $instance attribute in Foo and Bar types.
private static Foo,Bar::$instance = null;
?>
Example 8.2: Constant introduction
<?php
//Declare PEAR_LOG_DEBUG and PEAR_LOG_ERR constants in class Log.
Log::PEAR_LOG_DEBUG=7, Log::PEAR_LOG_ERR=3;
?>
Example 8.3: Method introduction
<?php
//Declare setLog method in all types prefixed by Bo.
public function Bo*::setLog(Log $log){
if($this->debug){
$log->setMask(Log::PEAR_LOG_DEBUG);
}else{
$log->setMask(Log::PEAR_LOG_ERROR);
}
$this->pearLog = $log;
}
?>