This will make callback be called in on the server side. We should use only one computed instead

@antfu Perhaps I'm misunderstanding a bit of Vue's reactivity system, so correct me if I'm wrong, but I believe what you suggest won't work (although, to be honest, I haven't tested it).

I initially thought about doing it like this:

computed(() => isMounted.value ? fn() : false);

However, as far as I know, computed tracks direct dependencies of the callback passed to it. The "single computed" has two dependencies:

• isMounted
• fn

fn is not reactive. But the contents of fn might be. Hence why the double computed, which has:

• isMounted
• Return of fn

Correct me if I'm wrong please.

Vue collects reactive deps automatically on the go. This means at the first run if isMounted is false, only isMounted is collected. Later once it flipped to true and fn get called, any reactive usage inside fn will be collected as well. So you don't have such concern

@antfu Done, squash commits as you deem necessary

I added a comment explaining why the useless check is added, if you prefer me to remove it I can do it no problem :)