5.5

Lua 5.5.0 was released on 22 Dec 2025. Its main new features are declarations for global variables, named vararg tables, more compact arrays, and major garbage collections done incrementally.

Here are the main changes introduced in Lua 5.5. The reference manual lists the incompatibilities that had to be introduced.

Main changes

• declarations for global variables
• named vararg tables
• for-loop variables are read only
• floats are printed in decimal with enough digits to be read back correctly.
• more levels for constructors
• table.create
• utf8.offset returns also final position of character
• external strings (that use memory not managed by Lua)
• new functions luaL_openselectedlibs and luaL_makeseed
• major garbage collections done incrementally
• more compact arrays (large arrays use about 60% less memory)
• lua.c loads 'readline' dynamically
• static (fixed) binaries (when loading a binary chunk in memory, Lua can reuse its original memory in some of the internal structures)
• dump and undump reuse all strings
• auxiliary buffer reuses buffer when it creates final string

5.4.8

The final release is Lua 5.4.8, released on 4 Jun 2025.

Here are the main changes introduced in Lua 5.4. The reference manual lists the incompatibilities that had to be introduced.

Main changes…

• new generational mode for garbage collection
• to-be-closed variables
• const variables
• userdata can have multiple user values
• new implementation for math.random
• warning system
• debug information about function arguments and returns
• new semantics for the integer 'for' loop
• optional 'init' argument to 'string.gmatch'
• new functions 'lua_resetthread' and 'coroutine.close'
• string-to-number coercions moved to the string library
• allocation function allowed to fail when shrinking a memory block
• new format '%p' in 'string.format'
• utf8 library accepts codepoints up to 2^31

5.4.7

Lua 5.4 was released on 29 Jun 2020. Its main new features are a new generational mode for garbage collection and const and to-be-closed variables.

Here are the main changes introduced in Lua 5.4. The reference manual lists the incompatibilities that had to be introduced.

Main changes…

• new generational mode for garbage collection
• to-be-closed variables
• const variables
• userdata can have multiple user values
• new implementation for math.random
• warning system
• debug information about function arguments and returns
• new semantics for the integer 'for' loop
• optional 'init' argument to 'string.gmatch'
• new functions 'lua_resetthread' and 'coroutine.close'
• string-to-number coercions moved to the string library
• allocation function allowed to fail when shrinking a memory block
• new format '%p' in 'string.format'
• utf8 library accepts codepoints up to 2^31

5.4.6

Lua 5.4 was released on 29 Jun 2020. Its main new features are a new generational mode for garbage collection and const and to-be-closed variables.

Here are the main changes introduced in Lua 5.4. The reference manual lists the incompatibilities that had to be introduced.

Main changes…

• new generational mode for garbage collection
• to-be-closed variables
• const variables
• userdata can have multiple user values
• new implementation for math.random
• warning system
• debug information about function arguments and returns
• new semantics for the integer 'for' loop
• optional 'init' argument to 'string.gmatch'
• new functions 'lua_resetthread' and 'coroutine.close'
• string-to-number coercions moved to the string library
• allocation function allowed to fail when shrinking a memory block
• new format '%p' in 'string.format'
• utf8 library accepts codepoints up to 2^31

5.4.5

Lua 5.4 was released on 29 Jun 2020. Its main new features are a new generational mode for garbage collection and const and to-be-closed variables.

Here are the main changes introduced in Lua 5.4. The reference manual lists the incompatibilities that had to be introduced.

Main changes…

• new generational mode for garbage collection
• to-be-closed variables
• const variables
• userdata can have multiple user values
• new implementation for math.random
• warning system
• debug information about function arguments and returns
• new semantics for the integer 'for' loop
• optional 'init' argument to 'string.gmatch'
• new functions 'lua_resetthread' and 'coroutine.close'
• string-to-number coercions moved to the string library
• allocation function allowed to fail when shrinking a memory block
• new format '%p' in 'string.format'
• utf8 library accepts codepoints up to 2^31

5.4.4

Lua 5.4 was released on 29 Jun 2020. Its main new features are a new generational mode for garbage collection and const and to-be-closed variables.

Here are the main changes introduced in Lua 5.4. The reference manual lists the incompatibilities that had to be introduced.

Main changes…

• new generational mode for garbage collection
• to-be-closed variables
• const variables
• userdata can have multiple user values
• new implementation for math.random
• warning system
• debug information about function arguments and returns
• new semantics for the integer 'for' loop
• optional 'init' argument to 'string.gmatch'
• new functions 'lua_resetthread' and 'coroutine.close'
• string-to-number coercions moved to the string library
• allocation function allowed to fail when shrinking a memory block
• new format '%p' in 'string.format'
• utf8 library accepts codepoints up to 2^31

5.4.3

Lua 5.4 was released on 29 Jun 2020. Its main new features are a new generational mode for garbage collection and const and to-be-closed variables.

Here are the main changes introduced in Lua 5.4. The reference manual lists the incompatibilities that had to be introduced.

Main changes…

• new generational mode for garbage collection
• to-be-closed variables
• const variables
• userdata can have multiple user values
• new implementation for math.random
• warning system
• debug information about function arguments and returns
• new semantics for the integer 'for' loop
• optional 'init' argument to 'string.gmatch'
• new functions 'lua_resetthread' and 'coroutine.close'
• string-to-number coercions moved to the string library
• allocation function allowed to fail when shrinking a memory block
• new format '%p' in 'string.format'
• utf8 library accepts codepoints up to 2^31

5.4.2

Lua 5.4 was released on 29 Jun 2020. Its main new features are a new generational mode for garbage collection and const and to-be-closed variables.

Here are the main changes introduced in Lua 5.4. The reference manual lists the incompatibilities that had to be introduced.

Main changes…

• new generational mode for garbage collection
• to-be-closed variables
• const variables
• userdata can have multiple user values
• new implementation for math.random
• warning system
• debug information about function arguments and returns
• new semantics for the integer 'for' loop
• optional 'init' argument to 'string.gmatch'
• new functions 'lua_resetthread' and 'coroutine.close'
• string-to-number coercions moved to the string library
• allocation function allowed to fail when shrinking a memory block
• new format '%p' in 'string.format'
• utf8 library accepts codepoints up to 2^31

5.4.1

Lua 5.4 was released on 29 Jun 2020. Its main new features are a new generational mode for garbage collection and const and to-be-closed variables.

Here are the main changes introduced in Lua 5.4. The reference manual lists the incompatibilities that had to be introduced.

Main changes…

• new generational mode for garbage collection
• to-be-closed variables
• const variables
• userdata can have multiple user values
• new implementation for math.random
• warning system
• debug information about function arguments and returns
• new semantics for the integer 'for' loop
• optional 'init' argument to 'string.gmatch'
• new functions 'lua_resetthread' and 'coroutine.close'
• string-to-number coercions moved to the string library
• allocation function allowed to fail when shrinking a memory block
• new format '%p' in 'string.format'
• utf8 library accepts codepoints up to 2^31

5.4

Lua 5.4 was released on 29 Jun 2020. Its main new features are a new generational mode for garbage collection and const and to-be-closed variables.

Here are the main changes introduced in Lua 5.4. The reference manual lists the incompatibilities that had to be introduced.

Main changes…

• new generational mode for garbage collection
• to-be-closed variables
• const variables
• userdata can have multiple user values
• new implementation for math.random
• warning system
• debug information about function arguments and returns
• new semantics for the integer 'for' loop
• optional 'init' argument to 'string.gmatch'
• new functions 'lua_resetthread' and 'coroutine.close'
• string-to-number coercions moved to the string library
• allocation function allowed to fail when shrinking a memory block
• new format '%p' in 'string.format'
• utf8 library accepts codepoints up to 2^31