islclosure

Tells you whether a function was written in Luau.

islclosure(func: function): boolean

Most commonly used to find user-script functions and look inside them.
For example, getconstants only works on Luau closures:

for _, fn in ipairs(getgc()) do
    if type(fn) == "function" then
        if islclosure(fn) then
            -- it's a LocalScript's/ModuleScript's Luau function!
            for i, k in ipairs(getconstants(fn)) do
                print(`constant {i}: {tostring(k)}`)
            end
        else
            -- it's an internal roblox's engine C function, pass
        end
    end
end

Parameters

Parameter	Type	Description
func	function	The function to check.

Returns

true if func is a Luau closure, false if it’s a C closure.

Example

Example 1

<<<<<<< HEAD
local isL = islclosure(print)
=======
-- islclosure(func: function): boolean
>>>>>>> 50e30f53759b0538759af25c9b271514aa2c9290

Lua closures are user-defined or script-defined Luau functions.