Provides a few basic functions for debugging code in Roblox. Unlike the
`Library.debug` library found in Lua natively, this version has been heavily
sandboxed. Roblox does, however, have debugging functionality similar to Lua's
native debugging functionality (see the `Class.DebuggerManager` class).


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.

The format of the returned traceback is **not defined** and may change at
any time; use only for debug diagnostics and error analytics. It's
recommended that you **never** parse the return value of this function for
specific information, such as script names or line numbers.


debug.traceback

message

level

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


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


thread

Allows programmatic inspection of the call stack.

- `thread` (thread) - A thread as returned by
  `Library.coroutine.create()`.
- `level` - A `number` to describe the point at which information from the
  call stack information should be returned.
  - 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. Out-of-bounds values result in no values returned.
- `options` - A string that represents the information to be returned. It
  must contain exactly 0 or 1 of each of the following characters and no
  others: `slnaf`
  - `s` - `Library.string`. The function source identifier, equal to the
    full name of the script the function is defined in
  - `l` - `number`. If `functionOrLevel` is a function, the line the
    function is defined on. If `functionOrLevel` is a number (examining a
    stack frame), the line number of the function call
  - `n` - `Library.string`. The name of the function, may be nil for
    anonymous functions and C functions without an assigned debug name.
  - `a` - `number`, `boolean`. Arity of the function, which refers to the
    parameter count and whether the function is variadic.
  - `f` - `function`. The function which was inspected.

This function differs from `Library.debug.traceback()` in that it
guarantees the format of the data it returns. This is useful not only for
general logging and filtering purposes, but also for sending the data to
systems expecting structured input, such as crash aggregation.

This function is similar to `Library.debug.getinfo`, an unavailable part
of the standard Lua library which serves a similar purpose.


debug.info

A thread as returned by `Library.coroutine.create()`, omit entirely to
use the current thread.


Determines at what level of the call stack the information returned
should describe.


options

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


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


Allows programmatic inspection of the call stack.

- `function` - A `function` to describe the point at which information
  from the call stack information should be returned.
- `options` - A string that represents the information to be returned. It
  must contain exactly 0 or 1 of each of the following characters and no
  others: `slnaf`
  - `s` - `Library.string`. The function source identifier, equal to the
    full name of the script the function is defined in
  - `l` - `number`. If `functionOrLevel` is a function, the line the
    function is defined on. If `functionOrLevel` is a number (examining a
    stack frame), the line number of the function call
  - `n` - `Library.string`. The name of the function, may be nil for
    anonymous functions and C functions without an assigned debug name.
  - `a` - `number`, `boolean`. Arity of the function, which refers to the
    parameter count and whether the function is variadic.
  - `f` - `function`. The function which was inspected.

This function differs from `Library.debug.traceback()` in that it
guarantees the format of the data it returns. This is useful not only for
general logging and filtering purposes, but also for sending the data to
systems expecting structured input, such as crash aggregation.

This function is similar to `Library.debug.getinfo`, an unavailable part
of the standard Lua library which serves a similar purpose.


function

Determines at what function of the call stack the information returned
should describe.


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


Allows programmatic inspection of the call stack.

- `level` - A `number` to describe the point at which information from the
  call stack information should be returned.
  - 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. Out-of-bounds values result in no values returned.
- `options` - A string that represents the information to be returned. It
  must contain exactly 0 or 1 of each of the following characters and no
  others: `slnaf`
  - `s` - `Library.string`. The function source identifier, equal to the
    full name of the script the function is defined in
  - `l` - `number`. If `functionOrLevel` is a function, the line the
    function is defined on. If `functionOrLevel` is a number (examining a
    stack frame), the line number of the function call
  - `n` - `Library.string`. The name of the function, may be nil for
    anonymous functions and C functions without an assigned debug name.
  - `a` - `number`, `boolean`. Arity of the function, which refers to the
    parameter count and whether the function is variadic.
  - `f` - `function`. The function which was inspected.

This function differs from `Library.debug.traceback()` in that it
guarantees the format of the data it returns. This is useful not only for
general logging and filtering purposes, but also for sending the data to
systems expecting structured input, such as crash aggregation.

This function is similar to `Library.debug.getinfo`, an unavailable part
of the standard Lua library which serves a similar purpose.


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


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


Starts profiling for a MicroProfiler label.


debug.profilebegin

label

The text that this MicroProfiler label displays.


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


debug.profileend

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


debug.setmemorycategory

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


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.


Default Value: {defaultValueStart}{defaultValueEnd}

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

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

setmemorycategory

Parameters

Returns

resetmemorycategory

Returns