Globals¶

Lua and Roblox global functions, from the Roblox creator-docs.

Luau globals¶

A list of functions and variables that are native to Luau.

Properties¶

`_G`¶

Supported

A table that is shared between all scripts of the same context level. Any value written to _G from one script is visible to every other script at that same context level, which makes it a simple way to share state between scripts.

-- Script A (sets a value)
_G.mySharedValue = "hello from Script A"

Note that relying on `_G` for cross-script communication introduces
ordering dependencies and makes code harder to reason about. Prefer
`Class.ModuleScript` for shared state when possible.

_G: Array

`_VERSION`¶

Supported

A global variable that holds a string containing the current interpreter version.

A global variable (not a function) that holds a string containing the current interpreter version.

_VERSION: string

Functions¶

`assert`¶

Supported

Throws an error if the provided value resolves to false or nil.

Throws an error if the provided value is false or nil. If the assertion passes, it returns all values passed to it.

assert(value: Variant, errorMessage: string = assertion failed!): Variant

`collectgarbage`¶

Check

Performs the specified operation of the garbage collector. Note that Roblox's Luau sandbox only allows the count option to be used (the total memory in use by Luau, in kilobytes), as other options can interfere with existing processes. Effectively, this makes Global.LuaGlobals.gcinfo() a superior alternative that should be used instead.

collectgarbage(operation: string): Variant

`error`¶

Supported

Halts thread execution and throws an error.

Terminates the last protected function called and outputs message as an error message. If the function containing the error is not called in a protected function such as pcall(), then the script which called the function will terminate. The error function itself never returns and acts like a script error.

The level argument specifies how to get the error position. With level 1 (the default), the error position is where the error function was called. Level 2 points the error to where the function that called error was called; and so on. Passing a level 0 avoids the addition of error position information to the message.

error(message: Variant, level: int = 1): ()

`gcinfo`¶

Check

Returns the total memory heap size in kilobytes. The number reflects the current heap consumption from the operating system perspective, which fluctuates over time as garbage collector frees objects.

gcinfo(): number

`getfenv`¶

Partial

Returns the current environment in use by the caller, as a dictionary.

If provided with a function, the environment of the function will be returned.
If provided with an integer, Global.LuaGlobals.getfenv() will provide the environment of the function at the provided stack level: Level 1 is the function calling Global.LuaGlobals.getfenv(). If stack is 0, Global.LuaGlobals.getfenv() returns the global environment of the current script. When using Global.LuaGlobals.getfenv() to get the current environment of a script, it will return the same table every time within the specific thread.

WARNING: This function allows uncontrolled change of the global/function environment and disables script optimizations. Changes to the environment are not tracked by the script analysis tooling and may result in missing or incorrect warnings. As a replacement, consider using debug.info() instead.

getfenv(stack: Variant = 1): table

Nova note: Legacy environment APIs exist but are sandbox-restricted.

`getmetatable`¶

Supported

Returns the metatable of the given value.

Returns the metatable of the given value t if it has one, otherwise returns nil. If t does have a metatable, and the __metatable metamethod is set, it returns that value instead.

t can be a value of any type, not only a table, and this function doesn't error when t isn't a table. However, it doesn't always return nil for non-table values. Strings and many Roblox types, such as Instance, have locked metatables, so this function returns the string "The metatable is locked" for them. To check whether a value uses a specific metatable, compare the result directly, such as getmetatable(value) == MyClass.

getmetatable(t: Variant): Variant

`ipairs`¶

Supported

Returns an iterator function and the table for use in a for loop.

Returns three values: an iterator function, the table t and the number 0. Each time the iterator function is called, it returns the next numerical index-value pair in the table. When used in a generic for-loop, the return values can be used to iterate over each numerical index in the table:

ipairs(t: Array): function, Array, int

`loadstring`¶

Supported

Returns the provided code as a function that can be executed.

Loads Luau code from a string and returns it as a function.

Unlike standard Lua 5.1, Roblox's Luau cannot load the compiled bytecode using loadstring().

loadstring() is disabled by default. For guidance around enabling it, see ServerScriptService.

WARNING: This method disables certain Luau optimizations on the returned function. Extreme caution should be taken when using Global.LuaGlobals.loadstring(); if your intention is to allow users to run code in your experience, make sure to protect the returned function's environment by using Global.LuaGlobals.getfenv() and Global.LuaGlobals.setfenv().

loadstring(contents: string, chunkname: string): Variant

`newproxy`¶

Check

Creates a blank userdata, with the option for it to have a metatable.

Creates a blank zero-size userdata with the option for it to have a metatable. If addMetatable is true, an empty metatable is created and assigned to the userdata; you can then retrieve it with Global.LuaGlobals.getmetatable() and populate it with metamethods. If addMetatable is false or omitted, the userdata has no metatable and only serves as a unique identity token.

Unlike host-created userdata (Roblox instances), a newproxy-created userdata always reports "userdata" from both Global.LuaGlobals.type() and typeof(); setting a __type metamethod on it does not change the typeof() result.

-- Create a proxy with a metatable to implement custom tostring
local proxy = newproxy(true)
local mt = getmetatable(proxy)

mt.__tostring = function()
    return "MyProxy"
end

print(tostring(proxy)) --> MyProxy
print(type(proxy)) --> userdata

newproxy(addMetatable: bool = False): userdata

`next`¶

Supported

An iterator function for use in for loops.

Returns the first key/value pair in the array. If a lastKey argument was specified then returns the next element in the array based on the key that provided. The order in which the indices are enumerated is not specified, even for numeric indices. To traverse a table in numeric order, use a numerical for loop or ipairs.

The behavior of next is undefined if, during the traversal, you assign any value to a non-existent field in the table. You may, however, modify existing fields. In particular, you may clear existing fields.

next(t: table, lastKey: Variant = nil): Variant, Variant

`pairs`¶

Supported

Returns an iterator function and the provided table for use in a for loop.

Returns an iterator function, the passed table t, and nil, so that the construction will iterate over all key/value pairs of that table when used in a generic for loop:

pairs(t: table): function, table, Variant

`pcall`¶

Supported

Runs the provided function and catches any error it throws, returning the function's success and its results.

Calls the function func with the given arguments in protected mode. This means that any error inside func is not propagated; instead, pcall() catches the error and returns a status code. Its first result is the status code (a boolean), which is true if the call succeeds without errors. In such case, pcall() also returns all results from the call, after this first result. In case of any error, pcall() returns false plus the error message.

pcall(func: function, args: Tuple): bool, Variant

`print`¶

Supported

Prints all provided values to the output.

Receives any number of arguments, and prints their values to the output. print is not intended for formatted output, but only as a quick way to show a value, typically for debugging. For a formatted output, use string.format(). On Roblox, print does not call tostring, but the __tostring metamethod still fires if the table has one.

print(params: Tuple): ()

`rawequal`¶

Supported

Returns whether v1 is equal to v2, bypassing their metamethods.

Checks whether v1 is equal to v2 without invoking the __eq metamethod. The comparison uses primitive equality rules: values of different types are never equal; nil equals only itself; numbers and vectors are compared by value; booleans are compared by value; and all reference types (tables, functions, threads, userdata) are compared by identity (same object in memory).

This is useful when you need to compare two tables or userdata objects that have an __eq metamethod and you want to test whether they are literally the same object rather than semantically equal.

local a = setmetatable({}, {__eq = function() return true end})
local b = setmetatable({}, {__eq = function() return true end})
print(a == b) --> true (metamethod fires)
print(rawequal(a, b)) --> false (different objects)
print(rawequal(a, a)) --> true (same object)

rawequal(v1: Variant, v2: Variant): bool

`rawget`¶

Supported

Gets the real value of table[index], bypassing any metamethods.

Gets the real value of table[index] without invoking the __index metamethod. The first argument must be a table; the second can be any non-nil value. If the key does not exist in the table itself, rawget() returns nil rather than walking up the metatable chain.

This is useful for inspecting a table's own stored fields when a metatable-based lookup chain would otherwise intercept the access.

local fallback = {x = 10}
local t = setmetatable({}, {__index = fallback})
print(t.x) --> 10 (found via __index)
print(rawget(t, "x")) --> nil (not in t itself)
t.y = 20
print(rawget(t, "y")) --> 20 (stored directly in t)

rawget(t: table, index: Variant): Variant

`rawlen`¶

Check

Returns the length of the string or table, bypassing any metamethods.

Returns the length of a table or string without invoking the __len metamethod. The argument must be a table or string; passing any other type raises an argument error. For tables, the result is equivalent to what the # operator would return before any metamethod fires; the length of the array portion as determined by the boundary search. For strings, it returns the byte count.

local t = setmetatable({1, 2, 3}, {__len = function() return 999 end})
print(#t) --> 999 (metamethod fires)
print(rawlen(t)) --> 3 (actual array length)
print(rawlen("hello")) --> 5

rawlen(t: table): number

`rawset`¶

Supported

Sets the real value of table[index], bypassing any metamethods.

Sets table[index] to value without invoking the __newindex metamethod. The first argument must be a table, the second is the key (must not be nil), and the third is the value to assign. Returns the table itself, which allows chained calls when building tables that have a __newindex guard.

This is the complement of Global.LuaGlobals.rawget() for write operations; use it when you need to bypass a proxy table's write interception.

local log = {}
local proxy = setmetatable({}, {
    __newindex = function(_, k, v)
        table.insert(log, k)
        rawset(proxy, k, v) -- actually store the value
    end
})
rawset(proxy, "x", 42) -- bypasses __newindex; no log entry
proxy.y = 7 -- triggers __newindex; log entry created
print(proxy.x, proxy.y) --> 42  7
print(#log) --> 1 (only "y" was logged)

rawset(t: table, index: Variant, value: Variant): table

`require`¶

Supported

Returns the value that was returned by the given ModuleScript, running it if it has not been run yet.

Runs the supplied ModuleScript and returns what the ModuleScript returned (usually a table or a function). If the ModuleScript has not been run yet, it will be executed.

If a string path is provided instead, it is first resolved to a ModuleScript relative to the script that called Global.LuaGlobals.require(), mimicking the Unix-like semantics of Luau's require() expression.

Specifically, require-by-string's resolution semantics are as follows:

Paths with the ./ prefix begin resolution at script.Parent.
Paths with the ../ prefix begin resolution at script.Parent.Parent.
Paths with the @self/ prefix begin resolution at script.
Paths with the @game/ prefix begin resolution at game.
Each non-prefix component in a given path corresponds to a child instance of the previous component. The exception to this is the .. component, which corresponds to the parent of the previous component.
If the desired ModuleScript is not present at the time that Global.LuaGlobals.require() is called, the call will fail and throw an error. In other words, require-by-string is non-blocking: it does not implicitly wait for a ModuleScript to be created.

To illustrate this, each pair of Global.LuaGlobals.require() expressions in the example below contains two functionally equivalent calls. Redundant parentheses have been added to clarify exactly how each path component maps onto an instance.

Once the return object is created by an initial Global.LuaGlobals.require() call of a ModuleScript, future Global.LuaGlobals.require() calls for the same ModuleScript (on the same side of the client-server boundary) will not run the code again. Instead, a reference to the same return object created by the initial Global.LuaGlobals.require() call will be supplied. This behavior allows for the sharing of values across different scripts, as multiple Global.LuaGlobals.require() calls from different scripts will reference the same returned object. If the returned object is a table, any values stored within the table are shared and accessible by any script requiring that ModuleScript.

As noted above, the "object sharing" behavior does not cross the client-server boundary. This means that if a ModuleScript is accessible to both the client and server (such as by being placed in ReplicatedStorage) and Global.LuaGlobals.require() is called from both a LocalScript as well as a Script, the code in the ModuleScript will be run twice, and the LocalScript will receive a distinct return object from the one received by the Script.

Also note that if the ModuleScript the user wants to run has been uploaded to Roblox (with the instance's name being MainModule), it can be loaded by using the Global.LuaGlobals.require() function on the asset ID of the ModuleScript, though only on the server.

require(module: ModuleScript | string | number): Variant

`select`¶

Supported

Returns all arguments after the given index.

Returns all arguments after argument number index. If negative, it will return from the end of the argument list.

If the index argument is set to "#", the number of arguments that were passed after it is returned.

select(index: Variant, args: Tuple): Tuple

`setfenv`¶

Partial

Sets the given function's environment.

Sets the environment to be used by the given function. f can be a function or a number that specifies the function at that stack level: Level 1 is the function calling setfenv(). setfenv() returns the given function.

If f is 0, then setfenv() changes the environment of the running thread and returns no values.

WARNING: This function allows uncontrolled change of the global/function environment and disables script optimizations. Changes to the environment are not tracked by the script analysis tooling and may result in missing or incorrect warnings.

setfenv(f: Variant, fenv: table): Variant

Nova note: Legacy environment APIs exist but are sandbox-restricted.

`setmetatable`¶

Supported

Sets the given table's metatable.

Sets the metatable for the given table t to newMeta. If newMeta is nil, the metatable of t is removed. Finally, this function returns the table t which was passed to it. If t already has a metatable whose __metatable metamethod is set, calling this on t raises an error.

setmetatable(t: table, newMeta: Variant): table

`tonumber`¶

Supported

Returns the provided value converted to a number, or nil if impossible.

Attempts to convert the arg into a number with a specified base to interpret the value in. If it cannot be converted, this function returns nil.

The base may be any integer between 2 and 36, inclusive. In bases above 10, the letter 'A' (in either upper or lower case) represents 10, 'B' represents 11, and so forth, with 'Z' representing 35. In base 10 (the default), the number may have a decimal part, as well as an optional exponent part. In other bases, only unsigned integers are accepted.

If a string begins with 0x and a base is not provided, the 0x is trimmed and the base is assumed to be 16, or hexadecimal.

tonumber(arg: Variant, base: int = 10): Variant

`tostring`¶

Supported

Returns the provided value converted to a string, or nil if impossible.

Receives an argument of any type and converts it to a string in a reasonable format. For complete control of how numbers are converted, use string.format. If the metatable of e has a __tostring metamethod, then it will be called with e as the only argument and will return the result.

tostring(e: Variant): string

`type`¶

Supported

Returns the basic type of the provided object.

Returns the type of its only argument, coded as a string. The possible results of this function are "nil" (a string, not the value nil), "number", "string", "boolean", "table", "vector", "function", "thread", "userdata", and "buffer". The buffer and vector primitives are additions from Luau, not from Lua.

type(v: Variant): string

`unpack`¶

Supported

Returns all elements from the given list as a tuple.

Returns the elements from the given list as separate return values, equivalent to list[i], list[i+1], ..., list[j]. By default, i is 1 and j is the length of list (as defined by the # operator). If the range is empty (i > j), no values are returned. An error is raised if the requested range is too large to fit on the stack.

local t = {10, 20, 30, 40, 50}
print(unpack(t)) --> 10  20  30  40  50
print(unpack(t, 2, 4)) --> 20  30  40

-- Common pattern: forwarding a stored argument list
local args = {1, "hello", true}
someFunction(unpack(args))

unpack(list: table, i: int = 1, j: int = #list): Variant

`xpcall`¶

Supported

Similar to Global.LuaGlobals.pcall() except it uses a custom error handler.

This function is similar to Global.LuaGlobals.pcall(), except that you can set a new error handler.

xpcall() calls function f in protected mode, using err as the error handler, and passes a list of arguments. Any error inside f is not propagated; instead, xpcall() catches the error, calls the err function with the original error object, and returns a status code. Its first result is the status code (a boolean), which is true if the call succeeds without errors. In this case, xpcall() also returns all results from the call, after this first result. In case of any error, xpcall() returns false plus the result from err.

Unlike Global.LuaGlobals.pcall(), the err function preserves the stack trace of function f, which can be inspected using debug.info() or debug.traceback().

xpcall(f: function, err: function, args: Tuple): bool, Variant

Roblox globals¶

Built-in functions and constants unique to Roblox.

Properties¶

`Enum`¶

Check

Contains all Enum objects.

A reference to the Enums data type, which stores all of the available enums that can be used on Roblox.

Enum: Enums

`game`¶

Check

Refers to the DataModel singleton, the root instance of a place's hierarchy.

A reference to the DataModel, which is the root Instance of Roblox's parent/child hierarchy.

game: DataModel

`plugin`¶

Check

Refers to a Plugin singleton when the code is run in the context of a Studio plugin.

A reference to the Plugin object that represents the plugin being run from this Script. This reference exists only in the context where a script is executed as a plugin and is not passed to ModuleScripts within the plugin. To use this reference in a ModuleScript, you must explicitly pass it.

plugin: Plugin

`shared`¶

Check

A table shared between all code running at the same execution context level.

A table that is shared across all scripts that share the same execution context level. This serves the exact same purpose as _G.

shared: Array

`script`¶

Check

A reference to the LuaSourceContainer object (Script, LocalScript, or ModuleScript) that is executing this code.

A reference to the script object that is executing the code you are writing. It can be either a Script, a LocalScript, or a ModuleScript. This variable is not available when executing code from Roblox Studio's command bar.

script: LuaSourceContainer

`workspace`¶

Check

A reference to the Workspace service, which contains all of the physical components of a place.

A reference to the Workspace service, which contains all of the physical components of a Roblox world.

workspace: Workspace

Functions¶

`delay`¶

Supported

Schedules a function to be called on the next Heartbeat after the given duration (in seconds) has passed, with throttling.

Schedules a function to be executed after delayTime seconds have passed, without yielding the current thread. This function allows multiple Luau threads to be executed in parallel from the same stack. The delay will have a minimum duration of 29 milliseconds, but this minimum may be higher depending on the target framerate and various throttling conditions. If the delayTime parameter is not specified, the minimum duration will be used.

delay(delayTime: number, callback: function): ()

Nova note: Prefer task.delay in new code.

`DebuggerManager`¶

Check

Refers to the legacy DebuggerManager class which acts as an interface for the Luau debugger feature.

Returns the legacy DebuggerManager class which acts as an interface for Roblox's Luau debugger feature.

This function is not recognized by Luau's analysis tool and will raise an undefined global warning.

DebuggerManager(): DebuggerManager

`elapsedTime`¶

Supported

Returns the amount of time in seconds that the current instance of Roblox has been running for.

Returns how much time has elapsed since the current instance of Roblox was started. In Roblox Studio, this begins counting up from the moment Roblox Studio starts running, not just when opening a place.

elapsedTime(): number

`PluginManager`¶

Check

Refers to the PluginManager, a deprecated singleton that was previously required to create plugins.

Returns the PluginManager which is a deprecated singleton that was previously required to create plugins. It still has some applicable uses, such as if you need to create a Plugin object from Studio's Command Bar.

PluginManager(): PluginManager

`printidentity`¶

Check

Prints "Current identity is X", where X corresponds to the current thread's security context level.

Prints Current identity is [ID] to the output, where [ID] corresponds to the current thread's security context level.

printidentity(prefix: string = Current identity is): ()

`settings`¶

Check

Returns the GlobalSettings object, which can be used to access the settings objects that are used in Roblox Studio's settings menu.

settings(): GlobalSettings

`spawn`¶

Supported

Calls a function immediately through the engine scheduler, with throttling.

Runs the specified callback function in a separate thread, without yielding the current thread.

The function will be executed the next time Roblox's Task Scheduler runs an update cycle. This delay will take at least 29 milliseconds but can arbitrarily take longer, depending on the target framerate and various throttling conditions.

The callback function is invoked with two arguments:

The first being the amount of time which elapsed from when spawn was called to when the function was invoked.
The second being equivalent to elapsedTime() or roughly how long the engine has been running.

spawn(callback: function): ()

Nova note: Prefer task.spawn in new code.

`stats`¶

Check

Returns the Stats service.

Returns the Stats service. It is preferred that developers use ServiceProvider.GetService() to retrieve it instead.

stats(): Stats

`tick`¶

Supported

Returns the amount of time in seconds since the Unix epoch according to this device's time.

Returns how much time has elapsed, in seconds, since the Unix epoch, on the current local session's computer. The Unix epoch is represented by 00:00:00 on 1 January 1970.

tick() isn't officially deprecated, but has a variety of issues. It can be off by up to one second and returns inconsistent results across time zones and operating systems. Use os.time(), os.clock(), or Global.RobloxGlobals.time() instead. Also consider DateTime.UnixTimestamp and DateTime.UnixTimestampMillis.

tick(): number

`time`¶

Supported

Returns the amount of time in seconds that has elapsed since the current game instance started running.

Returns the amount of time, in seconds, that has elapsed since the current game instance started running. If the current game instance is not running, this will be 0.

If Workspace.AuthorityMode is AuthorityMode.Server, this value is synchronized between client and server.

time(): number

`typeof`¶

Supported

Returns the type of the given object as a string, also supporting Roblox-specific types (e.g. Vector3).

Returns the type of the object specified, as a string. This function is more accurate than Luau's native type function, as it does not denote Roblox-specific types as userdata.

typeof(object: Variant): string

`UserSettings`¶

Check

Returns the UserSettings object, which is used to read information from the current user's game menu settings.

Returns the UserSettings object, which is used to read information from the current user's game menu settings.

UserSettings(): UserSettings

`version`¶

Check

Returns the current version of Roblox as a string, which includes the generation, version, patch and commit.

Returns the current version of Roblox as a string. The integers in the version string are separated by periods, and each integers represent the following, in order:

Generation - The current generation of the application shell that is hosting the client.
Version - The current release version of Roblox.
Patch - The current patch number for this version of Roblox.
Commit - The ID of the last internal commit that was accepted into this version of the client.

version(): string

`wait`¶

Supported

Yields the current thread until the specified amount of time in seconds have elapsed, with throttling.

Yields the current thread until the specified amount of seconds have elapsed.

The delay will have a minimum duration of 29 milliseconds, but this minimum may be higher depending on the target framerate and various throttling conditions. If the seconds parameter is not specified, the minimum duration will be used. This function returns:

Actual time yielded (in seconds).
Total time since the software was initialized (in seconds).

wait(seconds: number = 0.03): number, number

Nova note: Legacy 30 Hz wait is preserved; returns elapsed time.

`warn`¶

Supported

Behaves similarly to print, except with more distinct formatting (yellow); intended for messages which describe potential problems.

Behaves identically to Luau's print function, except the output is styled as a warning, with yellow text and a timestamp. This function accepts any number of arguments, and will attempt to convert them into strings which will then be joined together with spaces between them.

warn(params: Tuple): ()

`ypcall`¶

Check

Legacy function to work around an old task scheduling limitation of Global.LuaGlobals.pcall(); should not be used for new work (use Global.LuaGlobals.pcall() instead).

ypcall(f: function, args: Tuple): bool, Variant

Globals¶

Luau globals¶

Properties¶

_G¶

_VERSION¶

Functions¶

assert¶

collectgarbage¶

error¶

gcinfo¶

getfenv¶

getmetatable¶

ipairs¶

loadstring¶

newproxy¶

next¶

pairs¶

pcall¶

print¶

rawequal¶

rawget¶

rawlen¶

rawset¶

require¶

select¶

setfenv¶

setmetatable¶

tonumber¶

tostring¶

type¶

unpack¶

xpcall¶

Roblox globals¶

Properties¶

Enum¶

game¶

plugin¶

shared¶

script¶

workspace¶

Functions¶

delay¶

DebuggerManager¶

elapsedTime¶

PluginManager¶

printidentity¶

settings¶

spawn¶

stats¶

tick¶

time¶

typeof¶

UserSettings¶

version¶

wait¶

warn¶

ypcall¶

`_G`¶

`_VERSION`¶

`assert`¶

`collectgarbage`¶

`error`¶

`gcinfo`¶

`getfenv`¶

`getmetatable`¶

`ipairs`¶

`loadstring`¶

`newproxy`¶

`next`¶

`pairs`¶

`pcall`¶

`print`¶

`rawequal`¶

`rawget`¶

`rawlen`¶

`rawset`¶

`require`¶

`select`¶

`setfenv`¶

`setmetatable`¶

`tonumber`¶

`tostring`¶

`type`¶

`unpack`¶

`xpcall`¶

`Enum`¶

`game`¶

`plugin`¶

`shared`¶

`script`¶

`workspace`¶

`delay`¶

`DebuggerManager`¶

`elapsedTime`¶

`PluginManager`¶

`printidentity`¶

`settings`¶

`spawn`¶

`stats`¶

`tick`¶

`time`¶

`typeof`¶

`UserSettings`¶

`version`¶

`wait`¶

`warn`¶

`ypcall`¶