Luau Language Documentation

Luau provides two primary command-line tools:

1. luau: A command-line REPL and script runner. Note that the REPL runs in a sandboxed environment and cannot access the file system directly, except for require-ing modules.
2. luau-analyze: A command-line type checker and linter. It uses file configuration via --! comments or .luaurc files to produce errors and warnings.

Isocline is not thread-safe. All ic_readline_xxx and ic_print_xxx functions must be called from a single dedicated thread.

To use Isocline in an asynchronous application, run the Isocline functions in a blocking dedicated thread and communicate results back to your async event loop. To unblock a current ic_readline call from another thread (simulating a ctrl-c which returns NULL), use the thread-safe ic_async_stop() function.

bool ic_async_stop(void)

On Linux and macOS, you can build the binaries using make:

make config=release luau luau-analyze

To build Luau binaries from source on any platform, use CMake with the following commands:

mkdir cmake && cd cmake
cmake .. -DCMAKE_BUILD_TYPE=RelWithDebInfo
cmake --build . --target Luau.Repl.CLI --config RelWithDebInfo
cmake --build . --target Luau.Analyze.CLI --config RelWithDebInfo

You can install Luau by downloading compiled binaries from the official releases. Ensure the luau and luau-analyze binaries are added to your PATH or copied to a system directory like /usr/local/bin on Linux/macOS.

Alternatively, use these community-maintained package managers:

• macOS: brew install luau
• Arch Linux: pacman -Syu luau
• Alpine Linux: apk add luau
• Gentoo Linux: emerge dev-lang/luau (may require --autounmask=y)

For a minimal setup without dependencies, you can add Isocline as a git submodule and compile the source directly into your project.

1. Add the submodule: git submodule add https://github.com/daanx/isocline
2. Add isocline/src/isocline.c to your build rules.

$ git submodule add https://github.com/daanx/isocline

To build Isocline as a static library (libisocline.a or isocline.lib), clone the repository and use CMake to generate the build files.

$ git clone https://github.com/daanx/isocline
$ cd isocline
$ mkdir -p build/release
$ cd build/release
$ cmake ../..
$ cmake --build .

Luau provides two primary implementations of BaseCodeGenContext for managing native code generation state. Choose based on your VM architecture:

• StandaloneCodeGenContext: A VM-specific context. Use this for the "simple" implementation when native code generation is used with a single Luau VM.
• SharedCodeGenContext: Supports use from multiple Luau VMs concurrently. It allows for sharing of executable native code and related metadata across VMs.

Isocline supports 24-bit colors. If automatic detection fails, you can force a specific color palette by setting the COLORTERM environment variable. Use these values to control color depth:

• COLORTERM=truecolor: Enables 24-bit colors.
• COLORTERM=256color: Uses the ANSI 256 color palette.
• COLORTERM=16color: Uses the regular ANSI 16 color palette (8 normal, 8 bright).
• COLORTERM=8color: Uses bold for bright colors.
• COLORTERM=monochrome: Disables all color.

# Example of testing color support
gcc -o test_colors -Iinclude test/test_colors.c src/isocline.c
./test_colors
COLORTERM=truecolor ./test_colors
COLORTERM=16color ./test_colors

Luau supports executing code using native code generation. This can be enabled via several flags:

• --codegen: Standard native code generation.
• --codegen-cold: Includes functions that might not be profitable to natively compile.
• --codegen-perf: (Linux only) Enables native code generation and profiles using perf.