const [ sideA, sideB ] = duplexPair();

[Johnson1s]

What is the issue with the Streams Standard?

const [ sideA, sideB ] = duplexPair();

[ricea]

Could you elaborate? I cannot identify any action I can take based on the information you have provided.

[jasnell]

If I had to guess I'd say the ask for a convenience API the essentially implements:

function duplexPair() {
  const {
    readable : r1,
    writable: w1,
  } = new TransformStream();
  const {
    readable: r2,
    writable: w2,
  } = new TransformStream();
  return [
    { readable: r1, writable: w2 },
    { readable: r2, writable: w1 },
  ];
}

But with some additional lifecycle handling that ensures half-open is optionally handled and error state is propagated across the two halves?

Similar to Node.js' equivalent API: https://nodejs.org/docs/latest/api/stream.html#streamduplexpairoptions