scratch.txt

----- metadata representation experiment
// represents arbitrary metadata as an array
// each entry takes 2 slots in the array: name and value
/** @typedef {any[]} MetaDataArray */

/**
 * @param {MetaDataArray} m
 * @returns {number}
 */
export function metaCount(m) {
  return len(m) / 2;
}

/**
 * @param {MetaDataArray} m
 * @param {string} key
 * @returns {any}
 */
export function metaGet(m, key) {
  let n = len(m);
  for (let idx = 0; idx < n; idx += 2) {
    if (m[idx] === key) {
      return m[idx + 1];
    }
  }
  return undefined;
}

/**
 * @param {MetaDataArray} m
 * @param {number} i
 * @returns {string}
 */
export function metaKey(m, i) {
  return m[i * 2];
}

/**
 * @param {MetaDataArray} m
 * @param {number} i
 * @returns {string}
 */
export function metaValue(m, i) {
  return m[i * 2 + 1];
}

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