(module

  (func (export "leading0") (param $num i32) (result i32)
    ;; load number onto the stack
    local.get $num

    ;; check how many leading zeros and return the result
    i32.clz
  )

)

var url = "{%wasm-url%}";
await WebAssembly.instantiateStreaming(fetch(url), { console }).then(
  (result) => {
    const leading0 = result.instance.exports.leading0;

    console.log("Leading zeros: " + leading0(0b00000000_10000000_00000000_00000000));
  }
);