[closed] remove unit from array

[ZombieKnight]

Hi,
I'm trying to remove unit with id=$unit.id from array of units "side_7_retreat_micro_ai"
...
Any idea why my code isn't working?

Code: Select all

[lua]
                code=<<
local u_table = wml.variables["side_7_retreat_micro_ai"]
local u_id = wml.find_child(u_table, {id = wml.variables["unit.id"]})
wml.remove_children(wml.variables["side_7_retreat_micro_ai"], u_id)
>>
            [/lua]

[Ravana]

wml.find_child also gives you index, if u_table only contains tag of that name just use table.remove with that index.

And your version doesnt work because you havent read wml.remove_children documentation.

[ZombieKnight]

Why does

Code: Select all

for i, u in ipairs(wml.variables["side_7_retreat_micro_ai"]) do
print(u.id)
end

return nil?

[Ravana]

Because u.id is empty.

[ZombieKnight]

Solved with for loop.

[Spannerbag]

Hi,
I'm trying to remove unit with id=$unit.id from array of units "side_7_retreat_micro_ai"...

Just curious, but why lua?
A [for] loop would do that - and for me anyway, it's a lot easier to debug!

Cheers!
-- Spannerbag

[ZombieKnight]

Jup, [foreach] would work even better, but I want to learn lua better...
Thanks!

[white_haired_uncle]

Jup, [foreach] would work even better, but I want to learn lua better...
Thanks!

foreach doesn't play well with removing elements of the array it is iterating over. I don't try to remember the rules, I just use for if I'm going to remove anything.

[ZombieKnight]

Oh, true

[Spannerbag]

...I want to learn lua better...

Heh, I am currently going through the exactly same process starting from a position of knowing zero lua.
Note that the wiki isn't quite right so don't make my mistake of spending *hours* debugging something that will never work...

Good luck.

Cheers!
-- Spannerbag

[Celtic_Minstrel]

foreach doesn't play well with removing elements of the array it is iterating over. I don't try to remember the rules, I just use for if I'm going to remove anything.

You need to be careful removing elements with for, too – you could end up skipping over the next element when you remove one. The key is to iterate in reverse order. This is a big reason why the for tag provides reverse=yes in the first place when using array=.

That theoretically applies to foreach too. However, I don't think the foreach tag supports removing elements at all.

[ZombieKnight]

Jup it doesnt.
Jup I've got to to use reverse loops when removing elements.