square

Square Example

Demonstrates interception of direct function exports with primitive integer types.

Components

• Target: calculator (Python) exports add and subtract
• Advice: squarer (Rust) squares the return value of every intercepted call

WIT

world calculator-world {
  export add: func(a: s32, b: s32) -> s32;
  export subtract: func(a: s32, b: s32) -> s32;
}

Build

./build.sh

1. Generates the interceptor component from the WIT world using cargo run (interceptor CLI)
2. Builds the Python calculator target using componentize-py
3. Builds the Rust squarer advice using cargo component
4. Composes all three into composed.wasm using wac plug

Run

./run.sh

Calls add(3, 4) — the calculator returns 7, the squarer advice squares it to 49.