[SOLVED] [ZScript] A_SpawnItemEx returns 2 values?

[ADudeCalledLeo]

According to the wiki, this is A_SpawnItemEx's signature:

Code: Select all

bool, Actor A_SpawnItemEx (class<Actor> missile [, double xofs [, double yofs [, double zofs [, double xvel [, double yvel [, double zvel [, double angle [, int flags [, int failchance [, int tid]]]]]]]]]]) 

So, I assumed this would use Lua/Python-style syntax, and tried this:

Code: Select all

bool succ;
Actor spawned;
succ, spawned = A_SpawnItemEx("Shotgun");

But nope, that doesn't compile.

So my question is, how do I get both return values from this function?

[MFG38]

Try replacing Actor with class<Actor>.

[ADudeCalledLeo]

Try replacing Actor with class<Actor>.

That doesn't make sense to me. A_SpawnItemEx says it returns a pointer to the Actor it spawned, why would it return a class?
Besides, the error I got was something along the lines of "unexpected symbol", not "cannot cast X to Y".

[Cherno]

You have to encase multiple return values, like this:

Code: Select all

bool succ;
Actor spawned;
[succ, spawned] = A_SpawnItemEx("Shotgun");

That being said, you don't have to "catch" any of the return values. You could use none, one, or both if you wish.

[Tartlman]

While this question is pretty much answered, there's something to keep in mind:

A pointer to the spawned actor. If the actor fails to spawn due to chance or massacre, the returned value is null. When testing for space to spawn the actor in, the actor is spawned, tested and then immediately destroyed if it fails the test. The returned value in this case is still a pointer to the actor, not null. The space test is performed on monster-based actors only.

To avoid this headache, I highly recommend that you use spawn() combined with warp(). While the zdoom wiki page for warp() seems to be for ACS, note that it pretty much works the same in zscript except with an actor pointer instead of a TID, as far as I know. And no ugly junk variables in your code!

There are some cases where using spawnitemex is easier, of course.

[ADudeCalledLeo]

You have to encase multiple return values, like this:

Code: Select all

bool succ;
Actor spawned;
[succ, spawned] = A_SpawnItemEx("Shotgun");

That being said, you don't have to "catch" any of the return values. You could use none, one, or both if you wish.

Thank you!

[hideousdestructor]

To avoid this headache, I highly recommend that you use spawn() combined with warp(). While the zdoom wiki page for warp() seems to be for ACS, note that it pretty much works the same in zscript except with an actor pointer instead of a TID, as far as I know. And no ugly junk variables in your code!

There are some cases where using spawnitemex is easier, of course.

Why warp instead of just spawning at the desired coordinates and then setting pitch/angle? (not rhetorical question, I never use warp and forgot it even existed until now)

[AFADoomer]

^^ This

Code: Select all

Actor mo = Spawn("Shotgun", pos);
if (mo)
{
  mo.angle = angle;
  mo.pitch = pitch;
// etc....
}