text: let square
  
  function loadWebAssembly (fileName) {
    return fetch(fileName)
      .then(response => response.arrayBuffer())
      .then(buffer => WebAssembly.compile(buffer))
      .then(module => new WebAssembly.Instance(module))
  }
  
  loadWebAssembly('square.wasm').then(instance => {
    square = instance.exports._Z6squarei
  })
  