tomekwi/as.js

//
// as/object
// -------------------------------------------------------------------------------------------------
// Maps an array of `{key: "a", value: "b"}` pairs to a new `{a: "b"}` object.
//
/**
 * @function asObject
 *
 * @param {Array} array
 *    The array of key-value pairs to be mapped.
 *
 * @param {Object} [options]
 * - {Number} [depth=1]
 *    The depth to which the `array`'s pairs should be traversed. Set it to `Infinity` to map the
 *    whole structure.
 *
 * @returns {Object}
 *    A new object mapped from the array.
 */
export default function asObject (array, options) {
  // Parse options.
  var depth =
    ( !options || typeof options == "undefined"
    ? 1
    : options.depth
    );

  // End recursion if we've reached a depth of 0.
  if (!depth) return array;

  // Create an empty `result` object.
  var result = {};
  // For every `pair` of the given `array`:
  var i = 0; var l = array.length;
  while (i < l) { let pair = array[i++];
    // - skip the `pair` if it has no `key`
    if (!pair || !pair.hasOwnProperty("key")) continue;

    // - save `pair.value` as `value`
    let value = pair.value;

    // - recurse if the `value` is an array
    if (value instanceof Array) {
      value = asObject(value, {depth: depth - 1});
      }

    // - save `value` as `result[pair.key]`
    result[pair.key] = value;
    }

  // Return the `result`.
  return result;
  }