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getgc

getgc returns a list of non-dead garbage-collectable values. These include functions, userdatas, and optionally tables.

export type AnyFunction = (...any) -> (...any)
export type AnyTable = { [any]: any }

export type userdata = typeof(newproxy()) -- (1)

declare getgc:
    ((includeTables: true) -> { AnyTable | AnyFunction | userdata }) &
    ((includeTables: false?) -> { AnyFunction | userdata })
  1. Note that userdata is not an official Luau type, but we define it here for clarity - because getgc can return them as part of its results.

Parameters

Parameter Description
includeTables? If true, also includes tables in the returned list. Defaults to false.

Examples

Example 1

Function-only GC scan
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local dummy_table = {}
local function dummy_function() end
task.wait(0.05) -- Step a bit

for _, value in pairs(getgc()) do
    if value == dummy_function then
        print(`Found function: {dummy_function}`)
    elseif value == dummy_table then
        print(`Found table?: {dummy_table}`) -- This shouldn't print
    end
end

Example 2

Full GC scan including tables
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local dummy_table = {}
local function dummy_function() end
task.wait(0.05) -- Step a bit

for _, value in pairs(getgc(true)) do
    if value == dummy_function then
        print(`Found function: {dummy_function}`) -- Should print
    elseif value == dummy_table then
        print(`Found table: {dummy_table}`) -- Should also print
    end
end