RizzoMemory

MSc thesis project implementing Rizzo, a programming language based on the work of Rizzo by Patrick Bahr, with a focus on memory management and safety. The project includes:

• A compiler that translates Rizzo source code to C, leveraging reference counting for memory management.
• A C runtime library that provides memory management primitives, safety checks and the Rizzo advance and update semantics.
• A VS Code extension that integrates the Rizzo compiler and language server for an enhanced development experience with diagnostics, hover information, and code navigation (Rough implementation; not the focus of the MSc thesis).

Prerequisites

• OCaml (4.14+) and opam — for building the compiler
• Dune — OCaml build system (usually installed via opam)
• GCC or Clang — for compiling generated C code
• Node.js and npm — for the VS Code extension (optional)

Installation

Linux and macOS

Run the install script to download and install the latest version:

curl -fsSL https://raw.githubusercontent.com/itu-msc/RizzoMemory/main/install.sh | bash

To install a specific version, pass the --version flag:

curl -fsSL https://raw.githubusercontent.com/itu-msc/RizzoMemory/main/install.sh | bash -s -- --version v0.1.2

Security Note: You can download and inspect the script before running it:

curl -fsSL https://raw.githubusercontent.com/itu-msc/RizzoMemory/main/install.sh -o install.sh
# Review the script
cat install.sh
# Run it
bash install.sh

By default the installer:

• installs versioned toolchains under ${XDG_DATA_HOME:-$HOME/.local/share}/rizzo/toolchains
• updates ${XDG_DATA_HOME:-$HOME/.local/share}/rizzo/current
• links rizzoc and rizzolsp into $HOME/.local/bin

You can override the managed install root with RIZZO_HOME and the symlink directory with RIZZO_BIN_DIR.

Windows

Run the install script to download and install the latest version:

irm https://raw.githubusercontent.com/itu-msc/RizzoMemory/main/install.ps1 | iex

To install a specific version, use the scriptblock form so PowerShell can bind -Version:

& ([scriptblock]::Create((irm https://raw.githubusercontent.com/itu-msc/RizzoMemory/main/install.ps1))) -Version 0.2.1

By default the installer:

• installs versioned toolchains under $env:LOCALAPPDATA\Rizzo\toolchains
• updates $env:LOCALAPPDATA\Rizzo\current
• creates rizzoc.cmd and rizzolsp.cmd under $env:LOCALAPPDATA\Programs\Rizzo\bin
• adds that bin directory to the user Path

You can override the managed install root with RIZZO_HOME, the launcher directory with RIZZO_BIN_DIR, and skip the Path update with -NoPathUpdate.

If you want to inspect the installer first, download install.ps1 and run it locally instead of piping it to iex.

Development

• Build: opam exec -- dune build
• Run compiler on one or more source files: opam exec -- dune exec rizzoc ./examples/first.rizz

By default the compiler is quiet and only emits output.c. To inspect the intermediate ASTs while compiling, pass --print-ast to rizzoc.

How to Compile and Run Rizzo Programs

The compiler translates Rizzo source files (.rizz) to C (output.c), and triggers a C compile with either gcc or clang to produce an executable.

All you need to do is invoke the compiler on your Rizzo source file(s), and it will handle the rest:

rizzoc [more-files.rizz ...] <entrypoint.rizz>

For help run:

rizzoc --help

Implicit stdlib

File-based compilation and editor analysis now prepend a compiler-owned stdlib before user files are typechecked. The default stdlib lives in src/stdlib in the repository and installs next to the compiler under lib/rizzoc/stdlib. That means user .rizz files can use combinators such as map, zip, scan, and filter_map without copy-pasting their definitions first.

You can replace the default stdlib with --overwrite-stdpath <path>, where <path> can point to either a single .rizz file or a stdlib directory. You can also prepend extra files or directories with repeated -I <path> flags.

Multiple input files are compiled left-to-right after that implicit stdlib and any -I includes. Later files can refer to earlier files, but the reverse order is not supported yet.

Running from VS Code

Open any .rizz file and click the ▶ Run button in the editor title bar, or run the command Rizzo: Run Current File from the Command Palette.

The extension will:

1. Save the file
2. Compile it with rizzoc
3. Run the resulting binary in an integrated terminal

For Rizzo: Run Current File, the extension resolves rizzoc in this order:

1. rizzoLsp.compiler.command, if set
2. A local workspace build at _build/default/src/bin/main(.exe)
3. rizzoc on PATH

Configuration (settings.json):

Setting	Default	Description
rizzoLsp.compiler.command	(auto)	Path to rizzoc binary. Leave empty to auto-detect.
rizzoLsp.server.command	(auto)	Path to rizzolsp. Leave empty to auto-detect.
rizzoLsp.server.args	[]	Extra arguments passed when rizzoLsp.server.command is set explicitly.
rizzoLsp.server.workspaceFolder	[]	Optional workspace roots to use when resolving local builds during development.

LSP and VS Code extension

The Extension can be installed from the GitHub releases page, or built locally from the vscode-rizzo-lsp folder.

The extension starts rizzolsp automatically when you open a .rizz file. It resolves the server in this order:

1. rizzoLsp.server.command, if set
2. A local workspace build at _build/default/src/bin/rizzolsp(.exe)
3. rizzolsp on PATH

If you are developing inside this repository and want the extension to use the repo build, run opam exec -- dune build from the repository root first.

You can also run the server manually for development or debugging purposes.

To run the LSP server, use the command:

• LSP server: opam exec -- dune exec rizzolsp

VS Code extension development

The VS Code extension is located in the vscode-rizzo-lsp folder. It can easily be installed with

npm run ext:install:deps
npm run ext:install
npm run ext:install -- insiders

This installs the dependencies, builds the project and then installs the extension locally.

Debugging the extension

For development you might want to run the extension in a debug session, which allows you to set breakpoints and inspect variables in the LSP server code. To do this, you can run the debug configuration Run Rizzo Extension (repo root) from the repository root. This will launch a new VS Code window with the extension loaded. You can then open any .rizz file to see diagnostics, symbols, definitions, hover information, and completion suggestions provided by the LSP server.

• Run debug config: Run Rizzo Extension (repo root).
• Then open any .rizz file to get diagnostics, symbols, definition, hover, and completions (Ctrl+Space and typing-triggered suggestions).

Notes

• The extension contributes language configuration through package.json, so *.rizz files are automatically recognized.
• For true "just open folder and it works" without running a debug session, run the task rizzo: install local extension once (requires code CLI in PATH), then reopen VS Code.
• Rizzo: Check LSP Health shows which server command and working directory the extension is currently using.

LSP Commands

The extension provides several commands accessible via the Command Palette (Ctrl+Shift+P):

Command	Description
Rizzo: Run Current File	Compile and run the active .rizz file
Rizzo: Check LSP Health	Show LSP server status and configuration
Rizzo: Restart LSP Server	Restart the language server

A status bar item shows the current LSP state (starting/running/stopped).

Testing

Run the test suite with:

npm run test
# or
opam exec -- dune test

Tests cover parsing, type checking, transformations, and the language service.

Documentation

• Thesis document: See pdf/ for the LaTeX thesis document
• Development notes: See notes/ for design decisions and progress
• Syntax reference: See notes/syntax.md for language syntax overview