Question

I’m trying to make a debugging class for one of my websites, something similar to the logger class in Java.

<?php

abstract class DebugLevel
{
    const Notice = 1;
    const Info = 2;
    const Warning = 4;
    const Fatal = 8;
}

class Debug
{
    private static $level = DebugLevel::Fatal | DebugLevel::Warning | DebugLevel::Info | DebugLevel::Notice;


}

?>

I get a Parse error:

Parse error: syntax error, unexpected '|', expecting ',' or ';' in (script path) on line 13  

What’s wrong?

Answer 1

You can’t add logic to a class property (variable) or constant in PHP.

From the documentation:

This declaration may include an initialization, but this
initialization must be a constant value–that is, it must be able to
be evaluated at compile time and must not depend on run-time
information in order to be evaluated.

---

To set such a value use the __construct() function.

class Debug {

    public $level; // can not be a constant if you want to change it later!!!

    public function __construct() {
        $this->level = DebugLevel::Fatal | DebugLevel::Warning | DebugLevel::Info | DebugLevel::Notice;
    }

}

or maybe more elegant:

class Debug {

    public $level; // can not be a constant if you want to change it later!!!

    public function setLevel($level) {
        $this->level = $level;
    }

}

Then you can call this by:

$Debug = new Debug();
$Debug->setLevel(DebugLevel::Warning);