PHP class to manage read-only vars and arrays

Source code:

[sourcecode language=‘php’]

class Constants {     private $var_cache;

    public function set($key, $val)     {         if(isset($this->var_cache[$key]))         {             throw(new Exception(“Constants->get() error: var $key has already been defined”));         }         else         {             $this->var_cache[$key] = $val;         }     }

    public function get($key)     {         return $this->var_cache[$key];     } } [/sourcecode] Example usage:

[sourcecode language=‘php’] $constants = new Constants();

$constants->set(‘base_url’, ‘www.domain.com/path');

…

$img_src_url = $constants->get(‘base_url’).’/img/file.jpg’;

echo “”;

[/sourcecode]