Returns a traceback of the current function call stack as a string; in
other words, a description of the functions that have been called up to
this point. During debugging, this behaves like an error stack trace but
does not stop execution of the script.

The `level` parameter specifies what level of the call stack to consider,
with `1` being the call of `Library.debug.traceback()` itself, `2` being
the call of the function calling `Library.debug.traceback()`, and so on.
See the code sample below for an example of sequential function calls.

Note that this function will often return inaccurate results (compared to
the original source code) and that the format of the returned traceback
may change at any time. You should **not** parse the return value for
specific information such as script names or line numbers.

The following example includes sequential function calls; `fnB()` is
called, and it calls `fnA()` which then calls `Library.debug.traceback()`.

```lua
local function fnA()
	print(debug.traceback("Specific moment during fnA()"))
end

local function fnB()
	fnA()
end

-- Call function fnB() to begin traceback
fnB()
```


debug.traceback

message

level

The number of calls "up" the call stack to return.


Traceback of the current function call stack.


Returns a string of undefined format that describes the current function
call stack.


thread

A thread as returned by `Library.coroutine.create()`.


Allows programmatic inspection of the call stack. This function differs
from `Library.debug.traceback()` in that it guarantees the format of the
data it returns. This is useful for general logging and filtering purposes
as well as for sending the data to systems expecting structured input,
such as crash aggregation.

```lua
local function fnA()
	-- Output source identifier ("s") and line ("l") at levels 1 and 2
	print(debug.info(1, "sl"))  --> fnA() 3
	print(debug.info(2, "sl"))  --> fnA() 7
end

fnA()
```

Note that this function is similar to
[debug.getinfo](https://www.lua.org/pil/23.1.html), an unavailable part of
the standard Lua library which serves a similar purpose.


debug.info

Determines at what level of the call stack the information returned
should describe. A value of `1` represents the function which is
calling `Library.debug.info()`, a value of `2` represents the function
that called that function, and so on.


options

A string that describes what the returned information should
represent. It must only contain 0 or 1 instances of the characters
`slnaf`, each representing a piece of information:

- `s` ([string](/reference/engine/libraries/luau/strings)) — The function source identifier,
  equal to the full name of the script the function is defined in.
- `l` ([number](/reference/engine/libraries/luau/numbers)) — The line number of the function
  call represented by `level`.
- `n` ([string](/reference/engine/libraries/luau/strings)) — The name of the function; may be
  `nil` for anonymous functions and C functions without an assigned
  debug name.
- `a` ([number](/reference/engine/libraries/luau/numbers), [boolean](/reference/engine/libraries/luau/booleans)) —
  Arity of the function, which refers to the parameter count and
  whether the function is variadic.
- `f` ([function](/reference/engine/libraries/luau/functions)) — The function which was
  inspected.


Traverses the entire stack of current thread and returns a string
containing the call stack of target level details.


Allows programmatic inspection of the call stack. This function differs
from `Library.debug.traceback()` in that it guarantees the format of the
data it returns. This is useful for general logging and filtering purposes
as well as for sending the data to systems expecting structured input,
such as crash aggregation.

```lua
local function fnA()

end

local function fnB()

end

-- Output line ("l"), name ("n"), and identifier ("f") for both fnA() and fnB()
print(debug.info(fnA, "lnf"))  --> 1 fnA function: 0x75e3d3c398a81252
print(debug.info(fnB, "lnf"))  --> 5 fnB function: 0x6022a6dc5ccf4ab2
```

Note that this function is similar to
[debug.getinfo](https://www.lua.org/pil/23.1.html), an unavailable part of
the standard Lua library which serves a similar purpose.


function

The function of the call stack which the information returned should
describe.


A string that describes what the returned information should
represent. It must only contain 0 or 1 instances of the characters
`slnaf`, each representing a piece of information:

- `s` ([string](/reference/engine/libraries/luau/strings)) — The function source identifier,
  equal to the full name of the script the function is defined in.
- `l` ([number](/reference/engine/libraries/luau/numbers)) — The line that `function` is
  defined on.
- `n` ([string](/reference/engine/libraries/luau/strings)) — The name of the function; may be
  `nil` for anonymous functions and C functions without an assigned
  debug name.
- `a` ([number](/reference/engine/libraries/luau/numbers), [boolean](/reference/engine/libraries/luau/booleans)) —
  Arity of the function, which refers to the parameter count and
  whether the function is variadic.
- `f` ([function](/reference/engine/libraries/luau/functions)) — The function which was
  inspected.


Traverses the entire stack of current thread and returns a string
containing the call stack of target function details.


Traverses the entire stack of target thread and returns a string
containing the call stack of target level details.


Starts profiling for a
[MicroProfiler](/studio/microprofiler) label.


debug.profilebegin

label

The text that this
[MicroProfiler](/studio/microprofiler) label
displays.


Stops profiling for the most recent
[MicroProfiler](/studio/microprofiler) label that
`Library.debug.profilebegin()` opened.


debug.profileend

Stops profiling for the most recent label that
`Library.debug.profilebegin()` opened.


Returns the name of the current thread's active memory category.


debug.getmemorycategory

The current thread's active memory category.


Assigns a custom tag name to the current thread's memory category in the
[Developer Console](/studio/developer-console). Useful for
analyzing memory usage of multiple threads in the same script which would
otherwise be grouped together under the same tag/name. Returns the name of
the current thread's previous memory category.


debug.setmemorycategory

The current thread's previous memory category.


Assigns a custom tag to the current thread's memory category.


Resets the tag assigned by `Library.debug.setmemorycategory()` to the
automatically assigned value (typically, the script name).


debug.resetmemorycategory

debug

This library provides functions useful for debugging and profiling code.


An object that runs connected functions upon a specific occurrence.

Data Type

RBXScriptSignal

Luau

Tuple

Functions are blocks of code that can execute multiple times on command.

A double-precision floating-point number.

number

A sequence of characters, such as letters, numbers, and symbols.

string

A function that executes alongside the main thread.

Library

coroutine

void

Overview

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Tutorials

Reference

Resources

Design

Engine

Avatar

Cloud

This field may be set when creating a resource, but may not be modified by subsequent requests.

This field may be provided in requests, but will never be included in responses.

Per API Key: {maxInPeriod} requests every {periodInSeconds} seconds per IP Address

This field may be set on responses, but will be ignored in requests.

The following API key permissions are required to call this endpoint. For more
information on generating proper keys, see [Managing API Keys]({apiKeyReferenceDocLink}).

The following endpoints are available at paths relative to the base URL.

This string is formatted as a [FieldMask](/cloud/reference/types#fieldmask).

A JSON value can be `null`, `boolean`, `string`, `number`, `array`, or `object`.

The following scopes are required for your OAuth 2.0 application to use this endpoint. For more information on how to register an OAuth 2.0 application, see [App Registration and Review]({oauth2ReferenceDocLink}).

The following objects describe payloads that are accepted or returned. See each individual endpoint for more information on when these objects are used.

This string is formatted as a [Timestamp](/cloud/reference/types#timestamp).

This allows viewing information about your assets.

This allows uploading and updating assets to Roblox.

This allows you to view information about your Creator Store products.

This allows you to modify information about your Creator Store products.

This allows viewing information about your groups.

This allows you to manage group join requests for your account.

This allows viewing information about your inventory.

This grants the ability to publish messages on behalf of users.

This allows sending notifications from your experience to users

This allows listing secrets associated with your experience.

This allows creating and updating secrets associated with your experience.

Grants the ability to read place information.

Grants the ability to edit place information.

This operation grants access to publish new versions of experiences to Roblox.

Grants the ability to read experience information.

Grants the ability to edit experience information.

Allows you to view user restrictions in the experience.

Allows you to edit user restrictions in the experience.

Grants the ability to read user's premium and verified status.

This allows you to view a user's social accounts.

This enables Single Sign-On functionality

This grants access to read your profile information

Default Value: {defaultValueStart}{defaultValueEnd}

An array is an ordered list of values. Arrays are useful for storing collections of data.

A set of key-value pairs, where the keys can be any number, string, or object.

This function returns immediately if possible, but can yield the thread that called it until it can return a value.

{nameStart}name{nameEnd} is no longer supported or maintained by Roblox.

This math operation is no longer supported or maintained by Roblox.

This member doesn’t appear in the object browser and is not intended for widespread use.

This member is only accessible only through the command bar. Attempting to access this member from scripts causes an error.

This function can’t pause the Lua thread that called it.

Attempting to access this member in scripts causes an error. You might be able to access this member from Roblox Studio's property window.

This member doesn’t appear in Roblox Studio’s Object Browser.

You can’t create an instance of this class with the Instance.new constructor.

Roblox does not replicate this member across its server-client boundary.

Lua code can’t access this member. You might be able to change its value from the property window in Roblox Studio.

This object’s replication behavior is dependent on the player who owns it.

This member is accessible only through the command bar and plugins only. Attempting to access this member from scripts causes an error.

This property is read-only and is safe to read in unsynchronized threads. Attempting to write to it causes an error.

This member is read only. Attempting to write to this member causes an error.

This member is accessible only in CoreScripts.

Only Roblox CoreScripts can access this member, and it isn’t usable by Players.

You can read and write to this property safely from multiple threads.

This class is a top-level singleton. Retrieve an instance of this class with the GetService function.

Multiple threads can potentially write to this property, so it’s unsafe to read from unsynchronized threads.

This function pauses the Lua thread that called it until it returns a result. This doesn’t interrupt other scripts.

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debug

Summary

Functions

Functions

traceback

Parameters

Returns

traceback

Parameters

Returns

info

Parameters

Returns

info

Parameters

Returns

info

Parameters

Returns

profilebegin

Parameters

Returns

profileend

Returns

getmemorycategory

Returns

setmemorycategory

Parameters

Returns

resetmemorycategory

Returns