Default parameters based on function pattern

[xackery]

So I have a lua project that has generic methods like
function event_say(e)

The params are based on the file context, so if a file is named global_player.lua then it'll be ---@param e PlayerEventSay, otherwise as default it would be ---@param e NpcEventSay

Is there a way to set default parameters, that is, any time a function meets the pattern function event_say(e), and no params are set, to default to typing it to NpcEventSay? That way, I only need to override the defaults in player events, which are less common.

If not, what route is best to support file-sensitive param support like this? Plugins?

[tomlau10]

I don't quite understand what you want to achieve. Are you trying to annotate the param e in event_say() or what?
What do you mean by default to typing it to NpcEventSay?

• defaulting the type of e to NpcEventSay ?
• but if no params are set (e == nil?), how can you default e to something else?

---

I assume that e should be a required param of the function, only that when you are calling it in global_player.lua then you want e to be of type PlayerEventSay, otherwise e should be NpcEventSay type. (for accurate autocompletion hint I guess?)
If that's the case I think you can cast the event_say() into another function type in your global_player.lua.

• assuming event_say is a global function, the file containing the actual implementation of event_say:

---@class NpcEventSay
---@field npcId integer

---@param e NpcEventSay
function event_say(e) end

• at the top of your global_player.lua you can add this:

---@class PlayerEventSay
---@field playerId integer

---@type fun(e: PlayerEventSay)
local event_say = event_say

• In this way LuaLS will think that inside global_player.lua all calls to event_say can only accept PlayerEventSay, and all calls to the global event_say will only accept NpcEventSay