Function transformer

docs/source/examples/js/ipyvolume_v0.6.0-dev.1.js:17450–17457

(methods)

});

function transformer(methods) {
  return function(stream) {
    var s = new TransformStream;
    for (var key in methods) s[key] = methods[key];
    s.stream = stream;
    return s;
  };
}

function TransformStream() {}