Function _setStdwrite

src/js/streams.ts:464–496

(
  options: StdWriteOpts | {},
  setOps: (ops: Writer) => void,
  getDefaults: () => StdWriteOpts,
)

type StdWriteOptsAll = Partial<BatchedWriteHandler & RawWriteHandler & Writer>;

function _setStdwrite(
  options: StdWriteOpts | {},
  setOps: (ops: Writer) => void,
  getDefaults: () => StdWriteOpts,
) {
  let opts = options as StdWriteOptsAll;
  let { raw, isatty, batched, write } = opts;
  if (!raw && !write && isatty) {
    throw new TypeError(
      "Cannot set 'isatty' to true unless 'raw' or 'write' is provided",
    );
  }
  let nset = +!!raw + +!!batched + +!!write;
  if (nset > 1) {
    throw new TypeError(
      "At most one of 'raw', 'batched', and 'write' must be passed",
    );
  }
  if (nset === 0) {
    opts = getDefaults();
    ({ raw, isatty, batched, write } = opts);
  }
  if (raw) {
    setOps(new CharacterCodeWriter(opts as RawWriteHandler));
  }
  if (batched) {
    setOps(new StringWriter(batched.bind(opts)));
  }
  if (write) {
    setOps(opts as Writer);
  }
  refreshStreams();
}

/**
 * If in node, sets stdout to write directly to process.stdout and sets isatty(stdout)