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debug.getstack

C closures are not supported

This function will throw an error if the stack level points to a C closure, such as getstack(0).

debug.getstack retrieves values from the stack at the specified call level.

This function is useful for inspecting local variables or arguments at different layers of the stack frame. If no index is given, all values at that stack level are returned as a list.

function debug.getstack(level: number, index: number?): any | { any }

Parameters

Parameter Description
level The stack level to inspect. 1 is the current function.
index? The specific slot/index at that stack level to read.

Examples

Example 1

Retrieving multiple values from the stack
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local count = 0

local function recursive_function()
    count += 1
    if count > 6 then return end

    local a = 29
    local b = true
    local c = "Example"
    a += 1
    b = false
    c ..= "s"

    print(debug.getstack(1, count))
    recursive_function()
end

recursive_function()
-- Output (varies depending on Count):
-- 30
-- false
-- Examples
-- function: 0x... (print)
-- function: 0x... (getstack)
-- etc.

Example 2

Retrieving values from the caller's stack
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local function dummy_function()
    return "Hello"
end

local var = 5
var += 1

(function()
    print(debug.getstack(2)[1]()) -- Output: Hello
    print(debug.getstack(2)[2])   -- Output: 6
end)()