nodiscard in overloaded functions

[maattch]

There is a way to apply nodiscard to overloaded functions?

Here is a example of what i tried to do but did not worked:

---@nodiscard
---@overload fun(id: integer, autoCreate: true): table
---@nodiscard
---@overload fun(id: integer, autoCreate: false): table|nil
---@param id integer
---@return table
---@nodiscard
function get_thing_table(id) end

get_thing_table(1) -- warns about no discard
get_thing_table(1, true) -- no warnings
get_thing_table(1, false) -- no warnings

[tomlau10]

@overload fun(...) is quite limited, for example it doesn't support generic.

If possible, you can write you function annotation in a separate meta definition file, as stated in the wiki:
https://luals.github.io/wiki/annotations/#overload

If you are writing definition files, it is recommended to instead write multiple function definitions, one for each needed signature with its @param and @return annotations. This allows the functions to be as detailed as possible. Because the functions do not exist at runtime, this is acceptable.

demo

• meta.lua

---@meta

---@param id integer
---@param autoCreate true
---@return table
---@nodiscard
function get_thing_table(id, autoCreate) end

---@param id integer
---@param autoCreate false
---@return table|nil
---@nodiscard
function get_thing_table(id, autoCreate) end

---@param id integer
---@return table
---@nodiscard
function get_thing_table(id) end

• main.lua

get_thing_table(1) -- has warnings
get_thing_table(1, true) -- has warnings now
get_thing_table(1, false) -- has warnings now

[maattch]

The problem with doing it this way is that it now warn about redundant parameters.

local a = get_thing_table(1, true) -- warning about redundant parameter

[tomlau10]

it now warn about redundant parameters.

it shouldn't, since it can find a definition for the signature fun(integer, true)

demo

---

how did you test it?
unless you define your overload function signature incorrectly (eg typo in their function names)
otherwise redundant parameters should not be shown 🤔

demo with redundant parameters

notice that I incorrectly type get_thing_table as get_thing_table2 => which causes them to be new function instead of overload

[maattch]

Yeah, you are right.

The false warning i was getting is because i was testing it all inside the meta file (my mistake).
Thank you for your time.

Solved.