infocom-systems-design/node_modules/jotai/vanilla/utils.js

'use strict';

var vanilla = require('jotai/vanilla');

var RESET = Symbol(process.env.NODE_ENV !== 'production' ? 'RESET' : '');

function atomWithReset(initialValue) {
  var anAtom = vanilla.atom(initialValue, function (get, set, update) {
    var nextValue = typeof update === 'function' ? update(get(anAtom)) : update;
    set(anAtom, nextValue === RESET ? initialValue : nextValue);
  });
  return anAtom;
}

function atomWithReducer(initialValue, reducer) {
  return vanilla.atom(initialValue, function (get, set, action) {
    set(this, reducer(get(this), action));
  });
}

function _arrayLikeToArray(r, a) {
  (null == a || a > r.length) && (a = r.length);
  for (var e = 0, n = Array(a); e < a; e++) n[e] = r[e];
  return n;
}
function _createForOfIteratorHelperLoose(r, e) {
  var t = "undefined" != typeof Symbol && r[Symbol.iterator] || r["@@iterator"];
  if (t) return (t = t.call(r)).next.bind(t);
  if (Array.isArray(r) || (t = _unsupportedIterableToArray(r)) || e) {
    t && (r = t);
    var o = 0;
    return function () {
      return o >= r.length ? {
        done: true
      } : {
        done: false,
        value: r[o++]
      };
    };
  }
  throw new TypeError("Invalid attempt to iterate non-iterable instance.\nIn order to be iterable, non-array objects must have a [Symbol.iterator]() method.");
}
function _extends() {
  return _extends = Object.assign ? Object.assign.bind() : function (n) {
    for (var e = 1; e < arguments.length; e++) {
      var t = arguments[e];
      for (var r in t) ({}).hasOwnProperty.call(t, r) && (n[r] = t[r]);
    }
    return n;
  }, _extends.apply(null, arguments);
}
function _unsupportedIterableToArray(r, a) {
  if (r) {
    if ("string" == typeof r) return _arrayLikeToArray(r, a);
    var t = {}.toString.call(r).slice(8, -1);
    return "Object" === t && r.constructor && (t = r.constructor.name), "Map" === t || "Set" === t ? Array.from(r) : "Arguments" === t || /^(?:Ui|I)nt(?:8|16|32)(?:Clamped)?Array$/.test(t) ? _arrayLikeToArray(r, a) : void 0;
  }
}

function atomFamily(initializeAtom, areEqual) {
  var shouldRemove = null;
  var atoms = new Map();
  var listeners = new Set();
  var _createAtom = function createAtom(param) {
    var item;
    if (areEqual === undefined) {
      item = atoms.get(param);
    } else {
      for (var _iterator = _createForOfIteratorHelperLoose(atoms), _step; !(_step = _iterator()).done;) {
        var _step$value = _step.value,
          key = _step$value[0],
          value = _step$value[1];
        if (areEqual(key, param)) {
          item = value;
          break;
        }
      }
    }
    if (item !== undefined) {
      if (shouldRemove != null && shouldRemove(item[1], param)) {
        _createAtom.remove(param);
      } else {
        return item[0];
      }
    }
    var newAtom = initializeAtom(param);
    atoms.set(param, [newAtom, Date.now()]);
    notifyListeners('CREATE', param, newAtom);
    return newAtom;
  };
  var notifyListeners = function notifyListeners(type, param, atom) {
    for (var _iterator2 = _createForOfIteratorHelperLoose(listeners), _step2; !(_step2 = _iterator2()).done;) {
      var listener = _step2.value;
      listener({
        type: type,
        param: param,
        atom: atom
      });
    }
  };
  _createAtom.unstable_listen = function (callback) {
    listeners.add(callback);
    return function () {
      listeners.delete(callback);
    };
  };
  _createAtom.getParams = function () {
    return atoms.keys();
  };
  _createAtom.remove = function (param) {
    if (areEqual === undefined) {
      if (!atoms.has(param)) return;
      var _ref = atoms.get(param),
        atom = _ref[0];
      atoms.delete(param);
      notifyListeners('REMOVE', param, atom);
    } else {
      for (var _iterator3 = _createForOfIteratorHelperLoose(atoms), _step3; !(_step3 = _iterator3()).done;) {
        var _step3$value = _step3.value,
          key = _step3$value[0],
          _step3$value$ = _step3$value[1],
          _atom = _step3$value$[0];
        if (areEqual(key, param)) {
          atoms.delete(key);
          notifyListeners('REMOVE', key, _atom);
          break;
        }
      }
    }
  };
  _createAtom.setShouldRemove = function (fn) {
    shouldRemove = fn;
    if (!shouldRemove) return;
    for (var _iterator4 = _createForOfIteratorHelperLoose(atoms), _step4; !(_step4 = _iterator4()).done;) {
      var _step4$value = _step4.value,
        key = _step4$value[0],
        _step4$value$ = _step4$value[1],
        atom = _step4$value$[0],
        _createdAt = _step4$value$[1];
      if (shouldRemove(_createdAt, key)) {
        atoms.delete(key);
        notifyListeners('REMOVE', key, atom);
      }
    }
  };
  return _createAtom;
}

var getCached$2 = function getCached(c, m, k) {
  return (m.has(k) ? m : m.set(k, c())).get(k);
};
var cache1$3 = new WeakMap();
var memo3 = function memo3(create, dep1, dep2, dep3) {
  var cache2 = getCached$2(function () {
    return new WeakMap();
  }, cache1$3, dep1);
  var cache3 = getCached$2(function () {
    return new WeakMap();
  }, cache2, dep2);
  return getCached$2(create, cache3, dep3);
};
function selectAtom(anAtom, selector, equalityFn) {
  if (equalityFn === void 0) {
    equalityFn = Object.is;
  }
  return memo3(function () {
    var EMPTY = Symbol();
    var selectValue = function selectValue(_ref) {
      var value = _ref[0],
        prevSlice = _ref[1];
      if (prevSlice === EMPTY) {
        return selector(value);
      }
      var slice = selector(value, prevSlice);
      return equalityFn(prevSlice, slice) ? prevSlice : slice;
    };
    var derivedAtom = vanilla.atom(function (get) {
      var prev = get(derivedAtom);
      var value = get(anAtom);
      return selectValue([value, prev]);
    });
    derivedAtom.init = EMPTY;
    return derivedAtom;
  }, anAtom, selector, equalityFn);
}

var frozenAtoms = new WeakSet();
var _deepFreeze = function deepFreeze(value) {
  if (typeof value !== 'object' || value === null) {
    return value;
  }
  Object.freeze(value);
  var propNames = Object.getOwnPropertyNames(value);
  for (var _iterator = _createForOfIteratorHelperLoose(propNames), _step; !(_step = _iterator()).done;) {
    var name = _step.value;
    _deepFreeze(value[name]);
  }
  return value;
};
function freezeAtom(anAtom) {
  if (frozenAtoms.has(anAtom)) {
    return anAtom;
  }
  frozenAtoms.add(anAtom);
  var origRead = anAtom.read;
  anAtom.read = function (get, options) {
    return _deepFreeze(origRead.call(this, get, options));
  };
  if ('write' in anAtom) {
    var origWrite = anAtom.write;
    anAtom.write = function (get, set) {
      for (var _len = arguments.length, args = new Array(_len > 2 ? _len - 2 : 0), _key = 2; _key < _len; _key++) {
        args[_key - 2] = arguments[_key];
      }
      return origWrite.call.apply(origWrite, [this, get, function () {
        for (var _len2 = arguments.length, setArgs = new Array(_len2), _key2 = 0; _key2 < _len2; _key2++) {
          setArgs[_key2] = arguments[_key2];
        }
        if (setArgs[0] === anAtom) {
          setArgs[1] = _deepFreeze(setArgs[1]);
        }
        return set.apply(void 0, setArgs);
      }].concat(args));
    };
  }
  return anAtom;
}
function freezeAtomCreator(createAtom) {
  if (process.env.NODE_ENV !== 'production') {
    console.warn('[DEPRECATED] freezeAtomCreator is deprecated, define it on users end');
  }
  return function () {
    return freezeAtom(createAtom.apply(void 0, arguments));
  };
}

var getCached$1 = function getCached(c, m, k) {
  return (m.has(k) ? m : m.set(k, c())).get(k);
};
var cache1$2 = new WeakMap();
var memo2$1 = function memo2(create, dep1, dep2) {
  var cache2 = getCached$1(function () {
    return new WeakMap();
  }, cache1$2, dep1);
  return getCached$1(create, cache2, dep2);
};
var cacheKeyForEmptyKeyExtractor = {};
var isWritable = function isWritable(atom) {
  return !!atom.write;
};
var isFunction = function isFunction(x) {
  return typeof x === 'function';
};
function splitAtom(arrAtom, keyExtractor) {
  return memo2$1(function () {
    var mappingCache = new WeakMap();
    var _getMapping = function getMapping(arr, prev) {
      var mapping = mappingCache.get(arr);
      if (mapping) {
        return mapping;
      }
      var prevMapping = prev && mappingCache.get(prev);
      var atomList = [];
      var keyList = [];
      arr.forEach(function (item, index) {
        var key = keyExtractor ? keyExtractor(item) : index;
        keyList[index] = key;
        var cachedAtom = prevMapping && prevMapping.atomList[prevMapping.keyList.indexOf(key)];
        if (cachedAtom) {
          atomList[index] = cachedAtom;
          return;
        }
        var read = function read(get) {
          var prev = get(mappingAtom);
          var currArr = get(arrAtom);
          var mapping = _getMapping(currArr, prev == null ? void 0 : prev.arr);
          var index = mapping.keyList.indexOf(key);
          if (index < 0 || index >= currArr.length) {
            var prevItem = arr[_getMapping(arr).keyList.indexOf(key)];
            if (prevItem) {
              return prevItem;
            }
            throw new Error('splitAtom: index out of bounds for read');
          }
          return currArr[index];
        };
        var write = function write(get, set, update) {
          var prev = get(mappingAtom);
          var arr = get(arrAtom);
          var mapping = _getMapping(arr, prev == null ? void 0 : prev.arr);
          var index = mapping.keyList.indexOf(key);
          if (index < 0 || index >= arr.length) {
            throw new Error('splitAtom: index out of bounds for write');
          }
          var nextItem = isFunction(update) ? update(arr[index]) : update;
          if (!Object.is(arr[index], nextItem)) {
            set(arrAtom, [].concat(arr.slice(0, index), [nextItem], arr.slice(index + 1)));
          }
        };
        atomList[index] = isWritable(arrAtom) ? vanilla.atom(read, write) : vanilla.atom(read);
      });
      if (prevMapping && prevMapping.keyList.length === keyList.length && prevMapping.keyList.every(function (x, i) {
        return x === keyList[i];
      })) {
        mapping = prevMapping;
      } else {
        mapping = {
          arr: arr,
          atomList: atomList,
          keyList: keyList
        };
      }
      mappingCache.set(arr, mapping);
      return mapping;
    };
    var mappingAtom = vanilla.atom(function (get) {
      var prev = get(mappingAtom);
      var arr = get(arrAtom);
      var mapping = _getMapping(arr, prev == null ? void 0 : prev.arr);
      return mapping;
    });
    if (process.env.NODE_ENV !== 'production') {
      mappingAtom.debugPrivate = true;
    }
    mappingAtom.init = undefined;
    var splittedAtom = isWritable(arrAtom) ? vanilla.atom(function (get) {
      return get(mappingAtom).atomList;
    }, function (get, set, action) {
      switch (action.type) {
        case 'remove':
          {
            var index = get(splittedAtom).indexOf(action.atom);
            if (index >= 0) {
              var arr = get(arrAtom);
              set(arrAtom, [].concat(arr.slice(0, index), arr.slice(index + 1)));
            }
            break;
          }
        case 'insert':
          {
            var _index = action.before ? get(splittedAtom).indexOf(action.before) : get(splittedAtom).length;
            if (_index >= 0) {
              var _arr = get(arrAtom);
              set(arrAtom, [].concat(_arr.slice(0, _index), [action.value], _arr.slice(_index)));
            }
            break;
          }
        case 'move':
          {
            var index1 = get(splittedAtom).indexOf(action.atom);
            var index2 = action.before ? get(splittedAtom).indexOf(action.before) : get(splittedAtom).length;
            if (index1 >= 0 && index2 >= 0) {
              var _arr2 = get(arrAtom);
              if (index1 < index2) {
                set(arrAtom, [].concat(_arr2.slice(0, index1), _arr2.slice(index1 + 1, index2), [_arr2[index1]], _arr2.slice(index2)));
              } else {
                set(arrAtom, [].concat(_arr2.slice(0, index2), [_arr2[index1]], _arr2.slice(index2, index1), _arr2.slice(index1 + 1)));
              }
            }
            break;
          }
      }
    }) : vanilla.atom(function (get) {
      return get(mappingAtom).atomList;
    });
    return splittedAtom;
  }, arrAtom, keyExtractor || cacheKeyForEmptyKeyExtractor);
}

function atomWithDefault(getDefault) {
  var EMPTY = Symbol();
  var overwrittenAtom = vanilla.atom(EMPTY);
  if (process.env.NODE_ENV !== 'production') {
    overwrittenAtom.debugPrivate = true;
  }
  var anAtom = vanilla.atom(function (get, options) {
    var overwritten = get(overwrittenAtom);
    if (overwritten !== EMPTY) {
      return overwritten;
    }
    return getDefault(get, options);
  }, function (get, set, update) {
    var newValue = typeof update === 'function' ? update(get(anAtom)) : update;
    set(overwrittenAtom, newValue === RESET ? EMPTY : newValue);
  });
  return anAtom;
}

var isPromiseLike$3 = function isPromiseLike(x) {
  return typeof (x == null ? void 0 : x.then) === 'function';
};
function withStorageValidator(validator) {
  return function (unknownStorage) {
    var storage = _extends({}, unknownStorage, {
      getItem: function getItem(key, initialValue) {
        var validate = function validate(value) {
          if (!validator(value)) {
            return initialValue;
          }
          return value;
        };
        var value = unknownStorage.getItem(key, initialValue);
        if (isPromiseLike$3(value)) {
          return value.then(validate);
        }
        return validate(value);
      }
    });
    return storage;
  };
}
function createJSONStorage(getStringStorage, options) {
  if (getStringStorage === void 0) {
    getStringStorage = function getStringStorage() {
      try {
        return window.localStorage;
      } catch (e) {
        if (process.env.NODE_ENV !== 'production') {
          if (typeof window !== 'undefined') {
            console.warn(e);
          }
        }
        return undefined;
      }
    };
  }
  var lastStr;
  var lastValue;
  var storage = {
    getItem: function getItem(key, initialValue) {
      var _getStringStorage$get, _getStringStorage;
      var parse = function parse(str) {
        str = str || '';
        if (lastStr !== str) {
          try {
            lastValue = JSON.parse(str, options == null ? void 0 : options.reviver);
          } catch (_unused) {
            return initialValue;
          }
          lastStr = str;
        }
        return lastValue;
      };
      var str = (_getStringStorage$get = (_getStringStorage = getStringStorage()) == null ? void 0 : _getStringStorage.getItem(key)) != null ? _getStringStorage$get : null;
      if (isPromiseLike$3(str)) {
        return str.then(parse);
      }
      return parse(str);
    },
    setItem: function setItem(key, newValue) {
      var _getStringStorage2;
      return (_getStringStorage2 = getStringStorage()) == null ? void 0 : _getStringStorage2.setItem(key, JSON.stringify(newValue, options == null ? void 0 : options.replacer));
    },
    removeItem: function removeItem(key) {
      var _getStringStorage3;
      return (_getStringStorage3 = getStringStorage()) == null ? void 0 : _getStringStorage3.removeItem(key);
    }
  };
  var createHandleSubscribe = function createHandleSubscribe(subscriber) {
    return function (key, callback, initialValue) {
      return subscriber(key, function (v) {
        var newValue;
        try {
          newValue = JSON.parse(v || '');
        } catch (_unused2) {
          newValue = initialValue;
        }
        callback(newValue);
      });
    };
  };
  var subscriber;
  try {
    var _getStringStorage4;
    subscriber = (_getStringStorage4 = getStringStorage()) == null ? void 0 : _getStringStorage4.subscribe;
  } catch (_unused3) {}
  if (!subscriber && typeof window !== 'undefined' && typeof window.addEventListener === 'function' && window.Storage) {
    subscriber = function subscriber(key, callback) {
      if (!(getStringStorage() instanceof window.Storage)) {
        return function () {};
      }
      var storageEventCallback = function storageEventCallback(e) {
        if (e.storageArea === getStringStorage() && e.key === key) {
          callback(e.newValue);
        }
      };
      window.addEventListener('storage', storageEventCallback);
      return function () {
        window.removeEventListener('storage', storageEventCallback);
      };
    };
  }
  if (subscriber) {
    storage.subscribe = createHandleSubscribe(subscriber);
  }
  return storage;
}
var defaultStorage = createJSONStorage();
function atomWithStorage(key, initialValue, storage, options) {
  if (storage === void 0) {
    storage = defaultStorage;
  }
  var getOnInit = options == null ? void 0 : options.getOnInit;
  var baseAtom = vanilla.atom(getOnInit ? storage.getItem(key, initialValue) : initialValue);
  if (process.env.NODE_ENV !== 'production') {
    baseAtom.debugPrivate = true;
  }
  baseAtom.onMount = function (setAtom) {
    setAtom(storage.getItem(key, initialValue));
    var unsub;
    if (storage.subscribe) {
      unsub = storage.subscribe(key, setAtom, initialValue);
    }
    return unsub;
  };
  var anAtom = vanilla.atom(function (get) {
    return get(baseAtom);
  }, function (get, set, update) {
    var nextValue = typeof update === 'function' ? update(get(baseAtom)) : update;
    if (nextValue === RESET) {
      set(baseAtom, initialValue);
      return storage.removeItem(key);
    }
    if (isPromiseLike$3(nextValue)) {
      return nextValue.then(function (resolvedValue) {
        set(baseAtom, resolvedValue);
        return storage.setItem(key, resolvedValue);
      });
    }
    set(baseAtom, nextValue);
    return storage.setItem(key, nextValue);
  });
  return anAtom;
}

var isPromiseLike$2 = function isPromiseLike(x) {
  return typeof (x == null ? void 0 : x.then) === 'function';
};
function atomWithObservable(getObservable, options) {
  var returnResultData = function returnResultData(result) {
    if ('e' in result) {
      throw result.e;
    }
    return result.d;
  };
  var observableResultAtom = vanilla.atom(function (get) {
    var _Symbol$observable, _ref;
    var observable = getObservable(get);
    var itself = (_Symbol$observable = (_ref = observable)[Symbol.observable]) == null ? void 0 : _Symbol$observable.call(_ref);
    if (itself) {
      observable = itself;
    }
    var resolve;
    var makePending = function makePending() {
      return new Promise(function (r) {
        resolve = r;
      });
    };
    var initialResult = options && 'initialValue' in options ? {
      d: typeof options.initialValue === 'function' ? options.initialValue() : options.initialValue
    } : makePending();
    var setResult;
    var lastResult;
    var listener = function listener(result) {
      lastResult = result;
      resolve == null || resolve(result);
      setResult == null || setResult(result);
    };
    var subscription;
    var timer;
    var isNotMounted = function isNotMounted() {
      return !setResult;
    };
    var unsubscribe = function unsubscribe() {
      if (subscription) {
        subscription.unsubscribe();
        subscription = undefined;
      }
    };
    var start = function start() {
      if (subscription) {
        clearTimeout(timer);
        subscription.unsubscribe();
      }
      subscription = observable.subscribe({
        next: function next(d) {
          return listener({
            d: d
          });
        },
        error: function error(e) {
          return listener({
            e: e
          });
        },
        complete: function complete() {}
      });
      if (isNotMounted() && options != null && options.unstable_timeout) {
        timer = setTimeout(unsubscribe, options.unstable_timeout);
      }
    };
    start();
    var resultAtom = vanilla.atom(lastResult || initialResult);
    if (process.env.NODE_ENV !== 'production') {
      resultAtom.debugPrivate = true;
    }
    resultAtom.onMount = function (update) {
      setResult = update;
      if (lastResult) {
        update(lastResult);
      }
      if (subscription) {
        clearTimeout(timer);
      } else {
        start();
      }
      return function () {
        setResult = undefined;
        if (options != null && options.unstable_timeout) {
          timer = setTimeout(unsubscribe, options.unstable_timeout);
        } else {
          unsubscribe();
        }
      };
    };
    return [resultAtom, observable, makePending, start, isNotMounted];
  });
  if (process.env.NODE_ENV !== 'production') {
    observableResultAtom.debugPrivate = true;
  }
  var observableAtom = vanilla.atom(function (get) {
    var _get = get(observableResultAtom),
      resultAtom = _get[0];
    var result = get(resultAtom);
    if (isPromiseLike$2(result)) {
      return result.then(returnResultData);
    }
    return returnResultData(result);
  }, function (get, set, data) {
    var _get2 = get(observableResultAtom),
      resultAtom = _get2[0],
      observable = _get2[1],
      makePending = _get2[2],
      start = _get2[3],
      isNotMounted = _get2[4];
    if ('next' in observable) {
      if (isNotMounted()) {
        set(resultAtom, makePending());
        start();
      }
      observable.next(data);
    } else {
      throw new Error('observable is not subject');
    }
  });
  return observableAtom;
}

var cache1$1 = new WeakMap();
var memo1 = function memo1(create, dep1) {
  return (cache1$1.has(dep1) ? cache1$1 : cache1$1.set(dep1, create())).get(dep1);
};
var isPromiseLike$1 = function isPromiseLike(p) {
  return typeof (p == null ? void 0 : p.then) === 'function';
};
var LOADING = {
  state: 'loading'
};
function loadable(anAtom) {
  return memo1(function () {
    var loadableCache = new WeakMap();
    var refreshAtom = vanilla.atom(0);
    if (process.env.NODE_ENV !== 'production') {
      refreshAtom.debugPrivate = true;
    }
    var derivedAtom = vanilla.atom(function (get, _ref) {
      var setSelf = _ref.setSelf;
      get(refreshAtom);
      var value;
      try {
        value = get(anAtom);
      } catch (error) {
        return {
          state: 'hasError',
          error: error
        };
      }
      if (!isPromiseLike$1(value)) {
        return {
          state: 'hasData',
          data: value
        };
      }
      var promise = value;
      var cached1 = loadableCache.get(promise);
      if (cached1) {
        return cached1;
      }
      promise.then(function (data) {
        loadableCache.set(promise, {
          state: 'hasData',
          data: data
        });
        setSelf();
      }, function (error) {
        loadableCache.set(promise, {
          state: 'hasError',
          error: error
        });
        setSelf();
      });
      var cached2 = loadableCache.get(promise);
      if (cached2) {
        return cached2;
      }
      loadableCache.set(promise, LOADING);
      return LOADING;
    }, function (_get, set) {
      set(refreshAtom, function (c) {
        return c + 1;
      });
    });
    if (process.env.NODE_ENV !== 'production') {
      derivedAtom.debugPrivate = true;
    }
    return vanilla.atom(function (get) {
      return get(derivedAtom);
    });
  }, anAtom);
}

var getCached = function getCached(c, m, k) {
  return (m.has(k) ? m : m.set(k, c())).get(k);
};
var cache1 = new WeakMap();
var memo2 = function memo2(create, dep1, dep2) {
  var cache2 = getCached(function () {
    return new WeakMap();
  }, cache1, dep1);
  return getCached(create, cache2, dep2);
};
var isPromiseLike = function isPromiseLike(p) {
  return typeof (p == null ? void 0 : p.then) === 'function';
};
var defaultFallback = function defaultFallback() {
  return undefined;
};
function unwrap(anAtom, fallback) {
  if (fallback === void 0) {
    fallback = defaultFallback;
  }
  return memo2(function () {
    var promiseErrorCache = new WeakMap();
    var promiseResultCache = new WeakMap();
    var refreshAtom = vanilla.atom(0);
    if (process.env.NODE_ENV !== 'production') {
      refreshAtom.debugPrivate = true;
    }
    var promiseAndValueAtom = vanilla.atom(function (get, _ref) {
      var setSelf = _ref.setSelf;
      get(refreshAtom);
      var prev = get(promiseAndValueAtom);
      var promise = get(anAtom);
      if (!isPromiseLike(promise)) {
        return {
          v: promise
        };
      }
      if (promise !== (prev == null ? void 0 : prev.p)) {
        promise.then(function (v) {
          promiseResultCache.set(promise, v);
          setSelf();
        }, function (e) {
          promiseErrorCache.set(promise, e);
          setSelf();
        });
      }
      if (promiseErrorCache.has(promise)) {
        throw promiseErrorCache.get(promise);
      }
      if (promiseResultCache.has(promise)) {
        return {
          p: promise,
          v: promiseResultCache.get(promise)
        };
      }
      if (prev && 'v' in prev) {
        return {
          p: promise,
          f: fallback(prev.v),
          v: prev.v
        };
      }
      return {
        p: promise,
        f: fallback()
      };
    }, function (_get, set) {
      set(refreshAtom, function (c) {
        return c + 1;
      });
    });
    promiseAndValueAtom.init = undefined;
    if (process.env.NODE_ENV !== 'production') {
      promiseAndValueAtom.debugPrivate = true;
    }
    return vanilla.atom(function (get) {
      var state = get(promiseAndValueAtom);
      if ('f' in state) {
        return state.f;
      }
      return state.v;
    }, function (_get, set) {
      for (var _len = arguments.length, args = new Array(_len > 2 ? _len - 2 : 0), _key = 2; _key < _len; _key++) {
        args[_key - 2] = arguments[_key];
      }
      return set.apply(void 0, [anAtom].concat(args));
    });
  }, anAtom, fallback);
}

function atomWithRefresh(read, write) {
  var refreshAtom = vanilla.atom(0);
  if (process.env.NODE_ENV !== 'production') {
    refreshAtom.debugPrivate = true;
  }
  return vanilla.atom(function (get, options) {
    get(refreshAtom);
    return read(get, options);
  }, function (get, set) {
    for (var _len = arguments.length, args = new Array(_len > 2 ? _len - 2 : 0), _key = 2; _key < _len; _key++) {
      args[_key - 2] = arguments[_key];
    }
    if (args.length === 0) {
      set(refreshAtom, function (c) {
        return c + 1;
      });
    } else if (write) {
      return write.apply(void 0, [get, set].concat(args));
    } else if (process.env.NODE_ENV !== 'production') {
      throw new Error('refresh must be called without arguments');
    }
  });
}

function atomWithLazy(makeInitial) {
  var a = vanilla.atom(undefined);
  delete a.init;
  Object.defineProperty(a, 'init', {
    get: function get() {
      return makeInitial();
    }
  });
  return a;
}

exports.RESET = RESET;
exports.atomFamily = atomFamily;
exports.atomWithDefault = atomWithDefault;
exports.atomWithLazy = atomWithLazy;
exports.atomWithObservable = atomWithObservable;
exports.atomWithReducer = atomWithReducer;
exports.atomWithRefresh = atomWithRefresh;
exports.atomWithReset = atomWithReset;
exports.atomWithStorage = atomWithStorage;
exports.createJSONStorage = createJSONStorage;
exports.freezeAtom = freezeAtom;
exports.freezeAtomCreator = freezeAtomCreator;
exports.loadable = loadable;
exports.selectAtom = selectAtom;
exports.splitAtom = splitAtom;
exports.unstable_withStorageValidator = withStorageValidator;
exports.unwrap = unwrap;