For error handling I used a simple way;

• I have a function to store global shared variables, my implementation of such a function is similar to how an extension global is in C in the php source:
  
  PHP Code:

  function PG($name, $value = NULL)
{
    static $variables;

    if(!$variables)
    {
        $variables = Array();
    }

    if(func_num_args() > 1)
    {
        $variables[$name] = $value;
    }
    elseif(!array_key_exists($name, $variables))
    {
        return(false);
    }

    return($variables[$name]);
} 

  Then I allocate a default element to carry the non fatal errors, notice that this is an ArrayObject and now just a regular Array(). This is due to PHP doesn't support function dereferencing.
  
  PHP Code:

  PG('errors', new ArrayObject); 

• In the boostraper I also define a custom error and exception handler, set by set_[error|exception]_handler. The exception handler will check if an exception is fatal or not (depending on which one you send):
  
  PHP Code:

  function dingo_exception_handler(Exception $e)
{
    /* Simply consider any exception not of the default exception class fatal */
    if(get_class($e) == 'Exception')
    {
        PG('errors')->append($e->getMessage());

        return;
    }

    /* Format the error message, if you are in debug mode you can expose the path and line number (requires 'PG('debug')' defined */
    $format = '%s';

    if(PG('debug'))
    {
        $format = '%s in %s on line %d';
    }

    $message = sprintf('%s' . (PG('debug') ? ' in %s on line %d' : '')), $e->getMessage(), $e->getFile(), $e->getLine());

    /* $dingo->set_template_and_vars(), $dingo->view() */
} 

  And the same with the error handler:
  
  PHP Code:

  function dingo_error_handler($severity, $message, $file = NULL, $line = NULL)
{
    /* Respect the current error_reporting setting */
    if(!(error_reporting() & $severity))
    {
        return;
    }

    $fatal = false;

    switch($severity)
    {
        case(E_RECOVERABLE_ERROR):
        {
            $prefix = 'Recoverable error';
            $fatal     = true;
        }
        break;
        case(E_USER_ERROR):
        {
            $prefix = 'Fatal error';
            $fatal     = true;
        }
        break;
        case(E_NOTICE):
        case(E_USER_NOTICE):
        {
            $prefix = 'Notice';
        }
        break;
        /* E_DEPRECATED & E_USER_DEPRECATED, available as of PHP 5.3 - Use their numbers here to prevent redefining them and two E_NOTICE's */
        case(8192):
        case(16384):
        {
            $prefix = 'Deprecated';
        }
        case(E_STRICT):
        {
            $prefix = 'Strict standards';
        }
        break;
        default:
        {
            $prefix = 'Warning';
        }
    }

    $error = sprintf('%s: %s' . (PG('debug') ? ' in %s on line %s' : ''), $prefix, $message, ($file ? $file : 'unknown'), ($line ? $line : 'unknown'));

    if($fatal)
    {
        /* Handle a fatal error here, like exceptions */
    }
    elseif(PG('debug'))
    {
    /* Only add these non fatal errors to the error stack if we're in debug mode to prevent the user from seeing these */
        PG('errors')->append($error);
    }
} 

• When compiling the errors into an error message you can do like (basic HTML):
  
  PHP Code:

  $html = 'No errors!';

if(($errors = PG('errors')) && sizeof($errors))
{
    $html = '<h1>Errors</h1>' . 
        '<ul>';

    foreach($errors as $error)
    {
        $html .= '<li>' . $error . '</li>';
    }

    $html .= '</ul>';
}

echo($html); 


Hope this is easy enough to understand with the comments (as its 2:22 here, I better get some sleep)



ps. as a quick remark about option #3 in your previous post; you cannot use the name "use", its a reserved keyword as of PHP 5.3 ;)

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