Five years after releasing Lua 5.4, Lua 5.5 debuted today as the newest version of this lightweight and embeddable scripting language.
Lua 5.5 brings support for declarations of global variables, more compact arrays, and other refined language features. Large arrays in Lua are as using around 60% less memory with the Lua 5.5 build. Lua 5.5 also continues work on garbage collection “GC” improvements with a new generational mode and major garbage collections being done in an incremental manner.
The Lua.org README lists the Lua 5.5 highlights as:
– declarations for global variables
– 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
A nice Lua 5.5 release for ending out 2025.
