RFCs

Luau uses RFCs to discuss and document the language evolution process. They are hosted in a GitHub repository which accepts pull requests for corrections to existing RFCs as well as new RFCs.

If you’d like to submit a benign (grammatical, stylistic) correction, please open a pull request; all RFCs are in docs folder in the repository.

If you’d like to submit a new RFC, please read our guidelines first; RFCs often require a significant amount of design effort and precision to be considered.

Note that if you’d like to submit a substantial change to an existing RFC that is already implemented according to its Status field, you would need to submit a new amendment RFC instead of editing an existing one.

• Always call __eq when comparing for equality
• Amended Require Syntax and Resolution Semantics
• An official mascot for Luau
• Array-like table types
• Attributes (for Functions)
• Byte buffer type
• Change _VERSION global to “Luau”
• Compound assignment using op= syntax
• Configure analysis via .luaurc
• Default type alias type parameters
• Deprecate getfenv/setfenv
• Deprecate table.getn/foreach/foreachi
• Deprecated Attribute for Functions
• Disallow name T and name(T) in future syntactic extensions for type annotations
• Expanded Subtyping for Generic Function Types
• Extended numeric literal syntax
• Floor division operator
• Function Attribute Parameters
• Generalized iteration
• Generic functions
• Improved type checking rules of cast operator
• Leading | and & in types
• Local Type Inference
• Lower Bounds Calculation
• Named function type arguments
• Native Attribute for Functions
• New non-strict mode
• No support for user inlining (yet)
• Only strip optional properties from unsealed tables during subtyping
• Read-only properties
• Recursive type restriction
• Relaxing type assertions
• Require by String with Aliases
• Require by String with Relative Paths
• Reserve dollar sign ($) to be forever unused
• Sealed table subtyping
• Shared self types
• Singleton types
• Stricter utf8 library validation
• String interpolation
• Support __len metamethod for tables and rawlen function
• Syntax for table property access modifiers
• Type Error Suppression
• Type alias type packs
• Type ascriptions
• Typed variadics
• Unsealed table assignment creates an optional property
• Unsealed table literals
• User-Defined Type Functions
• Vector library
• Write-only properties
• bit32.byteswap
• bit32.countlz/countrz
• continue statement
• coroutine.close
• debug.info
• if-then-else expression
• index type function
• keyof and rawkeyof type functions
• math.map
• never and unknown types
• rawget type function
• string.pack/unpack/packsize from Lua 5.3
• table.clear
• table.clone
• table.create and table.find
• table.freeze