How to type this so Sumneko is happy

[muppet9010]

I have the below code and it warns me that the last line has the below error:

Can not infer type. Lua Diagnostic.(no-unknown)

Code:

---@class anObject
---@field name string|nil
---@field nickName string|nil

---@type anObject
local x = {
    name = "me",
    nickName = "M"
}

local fieldName = "name"
x[fieldName] = nil

I've tried adding type and as everywhere around it, but I can't get it to be happy other than disabling the specific diagnostic on this line. Is there a better way?

In my real code the value of fieldName is one of many strings and so my code is updating a specific field in the object based on inputs and various in function logic.

[carsakiller]

If you are going to be assigning random key names that can not be foreseen (and therefor documented with @field), you will have to do the following:

---@type table<string, any>
local x = {
    name = "me",
    nickName = "M"
}

local fieldName = "name"
x[fieldName] = nil

[muppet9010]

The field names are in the class, but yes they are unseen from Sumnekos viewpoint.

I will stick with disabling the warning on the line then as the class fields in my real code are all different types.

Ta

[carsakiller]

Ah, I see. Yes, it appears that the language server is not able to understand that fieldName is equal to the key that you are indexing. Unless you do some really janky stuff with types, like creating a custom type for that field... I think disabling the warning there is your best bet.