Debug.php
public static function enable(interfaces\handlers\Error $error = null, interfaces\handlers\Exception $exception = null, $threshold = null) : bool
    {
        // Only enable the Handlers once. See the class description for more on this.
        if (static::$enabled) {
            return false;
        }

        // Register the Handlers.
        static::$errorHandler     = handlers\Error::register($error, $threshold);
        static::$exceptionHandler = handlers\Exception::register($exception);

        return static::$enabled = true;
    }
public static function enable(interfaces\handlers\Error $error = null, interfaces\handlers\Exception $exception = null, $threshold = null) : bool
    {
        // Only enable the Handlers once. See the class description for more on this.
        if (static::$enabled) {
            return false;
        }

        // Register the Handlers.
        static::$errorHandler     = handlers\Error::register($error, $threshold);
        static::$exceptionHandler = handlers\Exception::register($exception);

        return static::$enabled = true;
    }
public static function enable ( interfaces \ handlers \ Error $ error = null , interfaces \ handlers \ Exception $ exception = null , $ threshold = null ) : bool { // Only enable the Handlers once. See the class description for more on this. if ( static :: $ enabled ) { return false ; } // Register the Handlers. static :: $ errorHandler = handlers \ Error :: register ( $ error , $ threshold ) ; static :: $ exceptionHandler = handlers \ Exception :: register ( $ exception ) ; return static :: $ enabled = true ; }
Enables the bundled Error and Exception Handlers by registering them with PHP.

Important note: The return values. When this method returns false, it merely means that the Handlers are
already registered and therefore could not be enabled again. This method will only return true for the call
that actually enables them. This is a little hack to make checking for certain conditions easier.

@param   interfaces\handlers\Error       $error      An optional already instantiated Error Handler instance.
If none is given, a new one will be instantiated.
@param   interfaces\handlers\Exception   $exception  An optional already instantiated Exception Handler instance.
If none is given, a new one will be instantiated.
@param   int                             $threshold  {@see handlers\Error::setThreshold()}
@return  bool                                        True when Debug was not yet enabled, false otherwise.
Enables the bundled Error and Exception Handlers by registering them with PHP .