moonbit-wasm-runner

A flexible CLI tool to run MoonBit‑generated WebAssembly modules using Wasmtime.
It supports interactive prompts, custom function invocation, argument passing with type annotations or autodetection, and verbose logging for debugging.

✨ Features

• Run .wasm files compiled from MoonBit or other sources.
• Provide the Wasm file path via CLI or interactively when omitted.
• Call a specific exported function with --func (default: _start).
• Pass arguments with --args:
  • Explicit type annotations: i32:5,f64:3.14,string:hello,bool:true
  • Autodetection: 5,3.14,hello,true,false
• Boolean support:
  • Autodetection: "true" / "false" → booleans; "1" / "0" → integers
  • Explicit: bool:true, bool:false, bool:1, bool:0
• Verbose logging with --verbose for detailed execution info.

📦 Installation

Clone the repository and build:

git clone https://github.com/isurfer21/moonbit-wasm-runner.git
cd moonbit-wasm-runner
cargo build --release

The binary will be available at:

target/release/moonbit-wasm-runner

🚀 Usage

Syntax

moonbit-wasm-runner <wasm_file_path> [OPTIONS]

Options

🧑‍💻 Examples

Run default _start function

moonbit-wasm-runner ./main.wasm

Run a specific function

moonbit-wasm-runner ./main.wasm --func add

Pass integers

moonbit-wasm-runner ./main.wasm --func add --args 5,10
moonbit-wasm-runner ./main.wasm --func add --args i32:5,i32:10

Pass floats

moonbit-wasm-runner ./main.wasm --func scale --args 3.14,2.71
moonbit-wasm-runner ./main.wasm --func scale --args f64:3.14,f64:2.71

Pass strings

moonbit-wasm-runner ./main.wasm --func concat --args hello,world
moonbit-wasm-runner ./main.wasm --func concat --args string:hello,string:world

Pass booleans

moonbit-wasm-runner ./main.wasm --func toggle --args true,false
moonbit-wasm-runner ./main.wasm --func toggle --args bool:true,bool:false

Verbose mode

moonbit-wasm-runner ./main.wasm --func add --args 42,7 --verbose

📖 Supported Types

📂 Project Structure

moonbit-wasm-runner/
├── src/
│   └── main.rs        # CLI + Wasmtime runner
├── Cargo.toml         # Dependencies (clap, wasmtime)
└── README.md          # Documentation

⚡ Dependencies

• clap v4 — modern CLI argument parsing.
• wasmtime v39 — WebAssembly runtime.

🧩 Future Improvements

• Add support for WASI imports (filesystem, stdout, etc.).
• Provide JSON output mode for structured results.
• Add benchmarking mode (--bench) to measure execution time.
• Integrate with MoonBit’s Wasm Component Model for modular builds.

📜 License

MIT License. See LICENSE for details.