Hi, I'm planning out my next game, and I was thinking about sharing the code between carts:

For example, there is cart a:

function a()
 cls()
end

And b:

-- load doesn't work so, it loads a cart
a() -- somehow

Any way to do that? Reload shouldn't help with code... Zep, maybe you could include this in 0.1.11?
Thanks!

Hey, it even existed in the console world.
Back in the day, you could by trainer carts to extend games with cheating functions!
Same concept here ;)

Such cart could cost a flat fee of 1000 tokens to make zep happy!

1000 is not a power of two, either 1024 or more, but I think, 8k is a good amount. I just need more for storing data like mobs and etc.

hey @Egor -- one thing I've been doing is keeping persistent things in user data (starts at 0x4300) and using reload() to pull in data from other carts as needed.

Ok, I feel kinda stupid now...

For some reason, I thought that the User Data was "Read Only" portion (e.g. the actual cart code).
I didn't realise it's another area we can push & pull data to. D'Oh!

#EveryDayIsASchoolDay

@LiquidDream: You were half right thinking that; it only exists as RAM and can't be written to a cart's ROM the way you can do with gfx/map/sfx data.

But during runtime you can use it to store decompressed data, a (partial) screenbuffer, fonts -- all kinds of neat stuff :p

And if you want to use multicart features, you can grab data to pop in there directly from another cart's gfx area or whatever.

It's unlikely that PICO-8 will ever be able to load more than 8k tokens of code at once (for the usual reasons -- keeping size restrictions meaningful etc.), but it sounds like in this case converting the data to binary and cstore()ing / reload()ing it might indeed be sufficient.

e.g.

-- store data (probably from a separate dev cart)
for i=1,100 do
 poke(0x42ff+i, mydat[i])
end
cstore(0,0x4300,100,"mydat.p8")

-- load data (from the main cart)
reload(0x4300,0,100,"mydat.p8")
mydat={}
for i=1,100 do
 mydat[i]=peek(0x42ff+i)
end

This example only works for numbers 0..255, of course -- if you need to store strings and other types of data it might not be the best approach.

Ok, thanks, zep. Then I should think @enargy's solution with interpreting functions. (I was planning to store enemies AI in the second cart)