[solved] How to store unit using custom wml tag

[ZombieKnight]

Hi
How to store unit using custom wml tag?
(Same way as [message] does, without [filter tag])
Thanks

[Celtic_Minstrel]

If you're asking how to store a unit in a WML variable from Lua, like [store_unit] does:

Code: Select all

local unit = wesnoth.units.find "unit_id" -- get the unit however you want, this example looks it up by its ID
wml.variables["your.variable[2].path"] = unit.__cfg

If you're asking how to find a unit based on the content of the ActionWML tag, like [message] does:

Code: Select all

function wesnoth.wml_actions.your_tag(cfg)
	local unit = wesnoth.units.find(cfg)[1] -- this assumes you want to take the first match – find returns all matching units as an array
	-- do stuff with unit here
end

Note that [message] is more complicated than that in order to handle the speaker= key, which isn't part of StandardUnitFilter. So, if you use the above example, you can't use speaker=. If you want, you can look at the implementation of the [message] tag in data/lua/wml/message.lua, but be warned that it is very complicated in order to handle a wide variety of situations.

[ZombieKnight]

But how to remove some values from the cfg (like message=)?

[Celtic_Minstrel]

Code: Select all

function wesnoth.wml_actions.your_tag(cfg)
	local filter = wml.shallow_literal(cfg)
	filter.key_you_want_to_remove = nil
	-- repeat for other keys
	wml.remove_children(filter, 'tag_you_want_to_remove', 'another_tag_you_want_to_remove')
	filter = wml.tovconfig(filter)
	-- now just use filter instead of cfg like in the previous example.
end

As long as everything you want to remove is directly in the tag (and not in some subtag), that should be sufficient. The use of shallow_literal and tovconfig ensures that any use of $this_unit in the filter will still function correctly. If you didn't care about that for some reason, you could substitute shallow_parsed and omit the tovconfig line. I don't really recommend doing that however.

[ZombieKnight]

I guess, I'll have to look into the wiki for those two new words...
Thanks that's exactly what I've been looking for!