Replace page render method and use original method

[---]

I've written a hook which replaces the page::render method. Based on a few conditions, I might want to output something different from what page::render would return.

So when my conditions aren't met, I want to use the return value of the original page::render method.

How can I do this?

At the moment I've got something like this:

function pageRenderHookMethod (HookEvent $event)
{
    if ('my condition' == true) {
        $event->replace = true;
        $event->return = 'my custom return value';
    } else {
        $event->return = 'original return value of page::render';
    }
}

But I don't know how to get the original return value of page::render because the would trigger my hooked method instead of the original method.

[kixe]

function pageRenderHookMethod (HookEvent $event)
{
    $default = $event->return;
	if ('my condition' == true) {
        $event->return = 'my custom return value';
    } else {
        $event->return = $default;
    }
}

If you hook after you don't need $event->replace = true;

[LostKobrakai]

You don't even need to set the return value to it's previous value. Just don't modify it if you don't need to:

function pageRenderHookMethod (HookEvent $event)
{
    if ('my condition' != true) return;
    $event->return = 'my custom return value';
}

But most often it's the better solution to use a before hook and prevent the original render function from running uselessly if it's return value might be replaced anyways:

function pageBeforeRenderHookMethod (HookEvent $event)
{
    if ('my condition' != true) return; // Let the original $page->render() do it's job
    $event->replace = true; // Skip the original $page->render()
    $event->return = 'custom value';
}