0.709

We skipped the release last week, but we're back today with some new additions to the VM and Native Code Generation (and as always, improvements to typechecking).

Analysis

• Fixed some instances of "unreduced table types" like { x: number } | { x: number }, especially for data-like arrays (extremely large tables that have the same element of a given type).

-- Prior, hovering would claim `t: {{number} | {number}}`, and now
-- we will claim it is a `{{number}}`
local t = {
    {1, 2, 3},
    {4, 5, 6}
}

• Fixed a bug where user defined type function could crash if passed too many arguments.
• Enables autocomplete to use type information for function arguments to suggest results when those types are variadic. For example:

local function foo(...: "Val1") end
foo(@1)

will now suggest "Val1"

• Partially annotated local statements with type packs on the right-hand-side (see example) are now correctly inferred. Prior, we mishandled this case in a way that caused subsequent assignments to assume the first element of the type pack corresponded to the first unannotated element:

local function foo(): (number, boolean, string)
    return 1, true "three"
end

-- Prior to this fix, we inferred that `y: number` for this statement ...
local x: number, y, z: string = foo()
--  ... similarly, this would have inferred `z: number` ...
local x: number, y: boolean, z = foo()
--  ... and this would have inferred `y: number` and `z: boolean`
local x: number, y, z = foo()

VM

• Fix a use-after-free in table.find.

Native Code Generation

• Fix a bug in NCG caused by using an incorrect operand in a buffer length check.
• NCG now unmaps executable pages when functions are garbage-collected.
• Provide a native implementation for math.isnan

---

Co-authored-by: Hunter Goldstein hgoldstein@roblox.com
Co-authored-by: Ilya Rezvov irezvov@roblox.com
Co-authored-by: Sora Kanosue skanosue@roblox.com
Co-authored-by: Varun Saini vsaini@roblox.com
Co-authored-by: Vyacheslav Egorov vegorov@roblox.com