jotai/umd/index.development.js

(function (global, factory) {
  typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports, require('react')) :
  typeof define === 'function' && define.amd ? define(['exports', 'react'], factory) :
  (global = typeof globalThis !== 'undefined' ? globalThis : global || self, factory(global.jotai = {}, global.React));
})(this, (function (exports, react) { 'use strict';

  function _extends() {
    _extends = Object.assign ? Object.assign.bind() : function (target) {
      for (var i = 1; i < arguments.length; i++) {
        var source = arguments[i];

        for (var key in source) {
          if (Object.prototype.hasOwnProperty.call(source, key)) {
            target[key] = source[key];
          }
        }
      }

      return target;
    };
    return _extends.apply(this, arguments);
  }

  function _unsupportedIterableToArray(o, minLen) {
    if (!o) return;
    if (typeof o === "string") return _arrayLikeToArray(o, minLen);
    var n = Object.prototype.toString.call(o).slice(8, -1);
    if (n === "Object" && o.constructor) n = o.constructor.name;
    if (n === "Map" || n === "Set") return Array.from(o);
    if (n === "Arguments" || /^(?:Ui|I)nt(?:8|16|32)(?:Clamped)?Array$/.test(n)) return _arrayLikeToArray(o, minLen);
  }

  function _arrayLikeToArray(arr, len) {
    if (len == null || len > arr.length) len = arr.length;

    for (var i = 0, arr2 = new Array(len); i < len; i++) arr2[i] = arr[i];

    return arr2;
  }

  function _createForOfIteratorHelperLoose(o, allowArrayLike) {
    var it = typeof Symbol !== "undefined" && o[Symbol.iterator] || o["@@iterator"];
    if (it) return (it = it.call(o)).next.bind(it);

    if (Array.isArray(o) || (it = _unsupportedIterableToArray(o)) || allowArrayLike && o && typeof o.length === "number") {
      if (it) o = it;
      var i = 0;
      return function () {
        if (i >= o.length) return {
          done: true
        };
        return {
          done: false,
          value: o[i++]
        };
      };
    }

    throw new TypeError("Invalid attempt to iterate non-iterable instance.\nIn order to be iterable, non-array objects must have a [Symbol.iterator]() method.");
  }

  var SUSPENSE_PROMISE = Symbol();
  var isSuspensePromise = function isSuspensePromise(promise) {
    return !!promise[SUSPENSE_PROMISE];
  };
  var isSuspensePromiseAlreadyCancelled = function isSuspensePromiseAlreadyCancelled(suspensePromise) {
    return !suspensePromise[SUSPENSE_PROMISE].c;
  };
  var cancelSuspensePromise = function cancelSuspensePromise(suspensePromise) {
    var _suspensePromise$SUSP = suspensePromise[SUSPENSE_PROMISE],
        basePromise = _suspensePromise$SUSP.b,
        cancelPromise = _suspensePromise$SUSP.c;

    if (cancelPromise) {
      var _promiseAbortMap$get;

      cancelPromise();
      (_promiseAbortMap$get = promiseAbortMap.get(basePromise)) == null ? void 0 : _promiseAbortMap$get();
    }
  };
  var isEqualSuspensePromise = function isEqualSuspensePromise(oldSuspensePromise, newSuspensePromise) {
    var oldOriginalPromise = oldSuspensePromise[SUSPENSE_PROMISE].o;
    var newOriginalPromise = newSuspensePromise[SUSPENSE_PROMISE].o;
    return oldOriginalPromise === newOriginalPromise || oldSuspensePromise === newOriginalPromise || isSuspensePromise(oldOriginalPromise) && isEqualSuspensePromise(oldOriginalPromise, newSuspensePromise);
  };
  var createSuspensePromise = function createSuspensePromise(basePromise, promise) {
    var suspensePromiseExtra = {
      b: basePromise,
      o: promise,
      c: null
    };
    var suspensePromise = new Promise(function (resolve) {
      suspensePromiseExtra.c = function () {
        suspensePromiseExtra.c = null;
        resolve();
      };

      promise.finally(suspensePromiseExtra.c);
    });
    suspensePromise[SUSPENSE_PROMISE] = suspensePromiseExtra;
    return suspensePromise;
  };
  var promiseAbortMap = new WeakMap();
  var registerPromiseAbort = function registerPromiseAbort(basePromise, abort) {
    promiseAbortMap.set(basePromise, abort);
  };

  var hasInitialValue = function hasInitialValue(atom) {
    return 'init' in atom;
  };

  var READ_ATOM = 'r';
  var WRITE_ATOM = 'w';
  var COMMIT_ATOM = 'c';
  var SUBSCRIBE_ATOM = 's';
  var RESTORE_ATOMS = 'h';
  var DEV_SUBSCRIBE_STATE = 'n';
  var DEV_GET_MOUNTED_ATOMS = 'l';
  var DEV_GET_ATOM_STATE = 'a';
  var DEV_GET_MOUNTED = 'm';
  var createStore = function createStore(initialValues) {

    var committedAtomStateMap = new WeakMap();
    var mountedMap = new WeakMap();
    var pendingMap = new Map();
    var stateListeners;
    var mountedAtoms;

    {
      stateListeners = new Set();
      mountedAtoms = new Set();
    }

    if (initialValues) {
      for (var _iterator = _createForOfIteratorHelperLoose(initialValues), _step; !(_step = _iterator()).done;) {
        var _step$value = _step.value,
            atom = _step$value[0],
            value = _step$value[1];
        var atomState = {
          v: value,
          r: 0,
          y: true,
          d: new Map()
        };

        {
          Object.freeze(atomState);

          if (!hasInitialValue(atom)) {
            console.warn('Found initial value for derived atom which can cause unexpected behavior', atom);
          }
        }

        committedAtomStateMap.set(atom, atomState);
      }
    }

    var suspensePromiseCacheMap = new WeakMap();

    var addSuspensePromiseToCache = function addSuspensePromiseToCache(version, atom, suspensePromise) {
      var cache = suspensePromiseCacheMap.get(atom);

      if (!cache) {
        cache = new Map();
        suspensePromiseCacheMap.set(atom, cache);
      }

      suspensePromise.then(function () {
        if (cache.get(version) === suspensePromise) {
          cache.delete(version);

          if (!cache.size) {
            suspensePromiseCacheMap.delete(atom);
          }
        }
      });
      cache.set(version, suspensePromise);
    };

    var cancelAllSuspensePromiseInCache = function cancelAllSuspensePromiseInCache(atom) {
      var versionSet = new Set();
      var cache = suspensePromiseCacheMap.get(atom);

      if (cache) {
        suspensePromiseCacheMap.delete(atom);
        cache.forEach(function (suspensePromise, version) {
          cancelSuspensePromise(suspensePromise);
          versionSet.add(version);
        });
      }

      return versionSet;
    };

    var versionedAtomStateMapMap = new WeakMap();

    var getVersionedAtomStateMap = function getVersionedAtomStateMap(version) {
      var versionedAtomStateMap = versionedAtomStateMapMap.get(version);

      if (!versionedAtomStateMap) {
        versionedAtomStateMap = new Map();
        versionedAtomStateMapMap.set(version, versionedAtomStateMap);
      }

      return versionedAtomStateMap;
    };

    var getAtomState = function getAtomState(version, atom) {
      if (version) {
        var versionedAtomStateMap = getVersionedAtomStateMap(version);

        var _atomState = versionedAtomStateMap.get(atom);

        if (!_atomState) {
          _atomState = getAtomState(version.p, atom);

          if (_atomState) {
            versionedAtomStateMap.set(atom, _atomState);
          }
        }

        return _atomState;
      }

      return committedAtomStateMap.get(atom);
    };

    var setAtomState = function setAtomState(version, atom, atomState) {
      {
        Object.freeze(atomState);
      }

      if (version) {
        var versionedAtomStateMap = getVersionedAtomStateMap(version);
        versionedAtomStateMap.set(atom, atomState);
      } else {
        var prevAtomState = committedAtomStateMap.get(atom);
        committedAtomStateMap.set(atom, atomState);

        if (!pendingMap.has(atom)) {
          pendingMap.set(atom, prevAtomState);
        }
      }
    };

    var createReadDependencies = function createReadDependencies(version, prevReadDependencies, dependencies) {
      if (prevReadDependencies === void 0) {
        prevReadDependencies = new Map();
      }

      if (!dependencies) {
        return prevReadDependencies;
      }

      var readDependencies = new Map();
      var changed = false;
      dependencies.forEach(function (atom) {
        var _getAtomState;

        var revision = ((_getAtomState = getAtomState(version, atom)) == null ? void 0 : _getAtomState.r) || 0;
        readDependencies.set(atom, revision);

        if (prevReadDependencies.get(atom) !== revision) {
          changed = true;
        }
      });

      if (prevReadDependencies.size === readDependencies.size && !changed) {
        return prevReadDependencies;
      }

      return readDependencies;
    };

    var setAtomValue = function setAtomValue(version, atom, value, dependencies, suspensePromise) {
      var atomState = getAtomState(version, atom);

      if (atomState) {
        if (suspensePromise && (!('p' in atomState) || !isEqualSuspensePromise(atomState.p, suspensePromise))) {
          return atomState;
        }

        if ('p' in atomState) {
          cancelSuspensePromise(atomState.p);
        }
      }

      var nextAtomState = {
        v: value,
        r: (atomState == null ? void 0 : atomState.r) || 0,
        y: true,
        d: createReadDependencies(version, atomState == null ? void 0 : atomState.d, dependencies)
      };
      var changed = !(atomState != null && atomState.y);

      if (!atomState || !('v' in atomState) || !Object.is(atomState.v, value)) {
        changed = true;
        ++nextAtomState.r;

        if (nextAtomState.d.has(atom)) {
          nextAtomState.d = new Map(nextAtomState.d).set(atom, nextAtomState.r);
        }
      } else if (nextAtomState.d !== atomState.d && (nextAtomState.d.size !== atomState.d.size || !Array.from(nextAtomState.d.keys()).every(function (a) {
        return atomState.d.has(a);
      }))) {
        changed = true;
        Promise.resolve().then(function () {
          flushPending(version);
        });
      }

      if (atomState && !changed) {
        return atomState;
      }

      setAtomState(version, atom, nextAtomState);
      return nextAtomState;
    };

    var setAtomReadError = function setAtomReadError(version, atom, error, dependencies, suspensePromise) {
      var atomState = getAtomState(version, atom);

      if (atomState) {
        if (suspensePromise && (!('p' in atomState) || !isEqualSuspensePromise(atomState.p, suspensePromise))) {
          return atomState;
        }

        if ('p' in atomState) {
          cancelSuspensePromise(atomState.p);
        }
      }

      var nextAtomState = {
        e: error,
        r: ((atomState == null ? void 0 : atomState.r) || 0) + 1,
        y: true,
        d: createReadDependencies(version, atomState == null ? void 0 : atomState.d, dependencies)
      };
      setAtomState(version, atom, nextAtomState);
      return nextAtomState;
    };

    var setAtomSuspensePromise = function setAtomSuspensePromise(version, atom, suspensePromise, dependencies) {
      var atomState = getAtomState(version, atom);

      if (atomState && 'p' in atomState) {
        if (isEqualSuspensePromise(atomState.p, suspensePromise)) {
          if (!atomState.y) {
            return _extends({}, atomState, {
              y: true
            });
          }

          return atomState;
        }

        cancelSuspensePromise(atomState.p);
      }

      addSuspensePromiseToCache(version, atom, suspensePromise);
      var nextAtomState = {
        p: suspensePromise,
        r: ((atomState == null ? void 0 : atomState.r) || 0) + 1,
        y: true,
        d: createReadDependencies(version, atomState == null ? void 0 : atomState.d, dependencies)
      };
      setAtomState(version, atom, nextAtomState);
      return nextAtomState;
    };

    var setAtomPromiseOrValue = function setAtomPromiseOrValue(version, atom, promiseOrValue, dependencies) {
      if (promiseOrValue instanceof Promise) {
        var suspensePromise = createSuspensePromise(promiseOrValue, promiseOrValue.then(function (value) {
          setAtomValue(version, atom, value, dependencies, suspensePromise);
        }).catch(function (e) {
          if (e instanceof Promise) {
            if (isSuspensePromise(e)) {
              return e.then(function () {
                readAtomState(version, atom, true);
              });
            }

            return e;
          }

          setAtomReadError(version, atom, e, dependencies, suspensePromise);
        }));
        return setAtomSuspensePromise(version, atom, suspensePromise, dependencies);
      }

      return setAtomValue(version, atom, promiseOrValue, dependencies);
    };

    var setAtomInvalidated = function setAtomInvalidated(version, atom) {
      var atomState = getAtomState(version, atom);

      if (atomState) {
        var nextAtomState = _extends({}, atomState, {
          y: false
        });

        setAtomState(version, atom, nextAtomState);
      } else {
        console.warn('[Bug] could not invalidate non existing atom', atom);
      }
    };

    var readAtomState = function readAtomState(version, atom, force) {
      if (!force) {
        var _atomState2 = getAtomState(version, atom);

        if (_atomState2) {
          if (_atomState2.y && 'p' in _atomState2 && !isSuspensePromiseAlreadyCancelled(_atomState2.p)) {
            return _atomState2;
          }

          _atomState2.d.forEach(function (_, a) {
            if (a !== atom) {
              if (!mountedMap.has(a)) {
                readAtomState(version, a);
              } else {
                var aState = getAtomState(version, a);

                if (aState && !aState.y) {
                  readAtomState(version, a);
                }
              }
            }
          });

          if (Array.from(_atomState2.d).every(function (_ref) {
            var a = _ref[0],
                r = _ref[1];
            var aState = getAtomState(version, a);
            return aState && !('p' in aState) && aState.r === r;
          })) {
            if (!_atomState2.y) {
              return _extends({}, _atomState2, {
                y: true
              });
            }

            return _atomState2;
          }
        }
      }

      var dependencies = new Set();

      try {
        var promiseOrValue = atom.read(function (a) {
          dependencies.add(a);
          var aState = a === atom ? getAtomState(version, a) : readAtomState(version, a);

          if (aState) {
            if ('e' in aState) {
              throw aState.e;
            }

            if ('p' in aState) {
              throw aState.p;
            }

            return aState.v;
          }

          if (hasInitialValue(a)) {
            return a.init;
          }

          throw new Error('no atom init');
        });
        return setAtomPromiseOrValue(version, atom, promiseOrValue, dependencies);
      } catch (errorOrPromise) {
        if (errorOrPromise instanceof Promise) {
          var suspensePromise = createSuspensePromise(errorOrPromise, errorOrPromise);
          return setAtomSuspensePromise(version, atom, suspensePromise, dependencies);
        }

        return setAtomReadError(version, atom, errorOrPromise, dependencies);
      }
    };

    var readAtom = function readAtom(readingAtom, version) {
      var atomState = readAtomState(version, readingAtom);
      return atomState;
    };

    var addAtom = function addAtom(version, addingAtom) {
      var mounted = mountedMap.get(addingAtom);

      if (!mounted) {
        mounted = mountAtom(version, addingAtom);
      }

      return mounted;
    };

    var canUnmountAtom = function canUnmountAtom(atom, mounted) {
      return !mounted.l.size && (!mounted.t.size || mounted.t.size === 1 && mounted.t.has(atom));
    };

    var delAtom = function delAtom(version, deletingAtom) {
      var mounted = mountedMap.get(deletingAtom);

      if (mounted && canUnmountAtom(deletingAtom, mounted)) {
        unmountAtom(version, deletingAtom);
      }
    };

    var invalidateDependents = function invalidateDependents(version, atom) {
      var mounted = mountedMap.get(atom);
      mounted == null ? void 0 : mounted.t.forEach(function (dependent) {
        if (dependent !== atom) {
          setAtomInvalidated(version, dependent);
          invalidateDependents(version, dependent);
        }
      });
    };

    var writeAtomState = function writeAtomState(version, atom, update) {
      var isSync = true;

      var writeGetter = function writeGetter(a, options) {
        var aState = readAtomState(version, a);

        if ('e' in aState) {
          throw aState.e;
        }

        if ('p' in aState) {
          if (options != null && options.unstable_promise) {
            return aState.p.then(function () {
              return writeGetter(a, options);
            });
          }

          {
            console.info('Reading pending atom state in write operation. We throw a promise for now.', a);
          }

          throw aState.p;
        }

        if ('v' in aState) {
          return aState.v;
        }

        {
          console.warn('[Bug] no value found while reading atom in write operation. This is probably a bug.', a);
        }

        throw new Error('no value found');
      };

      var setter = function setter(a, v) {
        var promiseOrVoid;

        if (a === atom) {
          if (!hasInitialValue(a)) {
            throw new Error('atom not writable');
          }

          var versionSet = cancelAllSuspensePromiseInCache(a);
          versionSet.forEach(function (cancelledVersion) {
            if (cancelledVersion !== version) {
              setAtomPromiseOrValue(cancelledVersion, a, v);
            }
          });
          var prevAtomState = getAtomState(version, a);
          var nextAtomState = setAtomPromiseOrValue(version, a, v);

          if (prevAtomState !== nextAtomState) {
            invalidateDependents(version, a);
          }
        } else {
          promiseOrVoid = writeAtomState(version, a, v);
        }

        if (!isSync) {
          flushPending(version);
        }

        return promiseOrVoid;
      };

      var promiseOrVoid = atom.write(writeGetter, setter, update);
      isSync = false;
      return promiseOrVoid;
    };

    var writeAtom = function writeAtom(writingAtom, update, version) {
      var promiseOrVoid = writeAtomState(version, writingAtom, update);
      flushPending(version);
      return promiseOrVoid;
    };

    var isActuallyWritableAtom = function isActuallyWritableAtom(atom) {
      return !!atom.write;
    };

    var mountAtom = function mountAtom(version, atom, initialDependent) {
      var mounted = {
        t: new Set(initialDependent && [initialDependent]),
        l: new Set()
      };
      mountedMap.set(atom, mounted);

      {
        mountedAtoms.add(atom);
      }

      var atomState = readAtomState(undefined, atom);
      atomState.d.forEach(function (_, a) {
        var aMounted = mountedMap.get(a);

        if (aMounted) {
          aMounted.t.add(atom);
        } else {
          if (a !== atom) {
            mountAtom(version, a, atom);
          }
        }
      });

      if (isActuallyWritableAtom(atom) && atom.onMount) {
        var setAtom = function setAtom(update) {
          return writeAtom(atom, update, version);
        };

        var onUnmount = atom.onMount(setAtom);
        version = undefined;

        if (onUnmount) {
          mounted.u = onUnmount;
        }
      }

      return mounted;
    };

    var unmountAtom = function unmountAtom(version, atom) {
      var _mountedMap$get;

      var onUnmount = (_mountedMap$get = mountedMap.get(atom)) == null ? void 0 : _mountedMap$get.u;

      if (onUnmount) {
        onUnmount();
      }

      mountedMap.delete(atom);

      {
        mountedAtoms.delete(atom);
      }

      var atomState = getAtomState(version, atom);

      if (atomState) {
        if ('p' in atomState) {
          cancelSuspensePromise(atomState.p);
        }

        atomState.d.forEach(function (_, a) {
          if (a !== atom) {
            var mounted = mountedMap.get(a);

            if (mounted) {
              mounted.t.delete(atom);

              if (canUnmountAtom(a, mounted)) {
                unmountAtom(version, a);
              }
            }
          }
        });
      } else {
        console.warn('[Bug] could not find atom state to unmount', atom);
      }
    };

    var mountDependencies = function mountDependencies(version, atom, atomState, prevReadDependencies) {
      var dependencies = new Set(atomState.d.keys());
      prevReadDependencies == null ? void 0 : prevReadDependencies.forEach(function (_, a) {
        if (dependencies.has(a)) {
          dependencies.delete(a);
          return;
        }

        var mounted = mountedMap.get(a);

        if (mounted) {
          mounted.t.delete(atom);

          if (canUnmountAtom(a, mounted)) {
            unmountAtom(version, a);
          }
        }
      });
      dependencies.forEach(function (a) {
        var mounted = mountedMap.get(a);

        if (mounted) {
          mounted.t.add(atom);
        } else if (mountedMap.has(atom)) {
          mountAtom(version, a, atom);
        }
      });
    };

    var flushPending = function flushPending(version) {
      if (version) {
        var versionedAtomStateMap = getVersionedAtomStateMap(version);
        versionedAtomStateMap.forEach(function (atomState, atom) {
          var committedAtomState = committedAtomStateMap.get(atom);

          if (atomState !== committedAtomState) {
            var mounted = mountedMap.get(atom);
            mounted == null ? void 0 : mounted.l.forEach(function (listener) {
              return listener(version);
            });
          }
        });
        return;
      }

      while (pendingMap.size) {
        var pending = Array.from(pendingMap);
        pendingMap.clear();
        pending.forEach(function (_ref2) {
          var atom = _ref2[0],
              prevAtomState = _ref2[1];
          var atomState = getAtomState(undefined, atom);

          if (atomState && atomState.d !== (prevAtomState == null ? void 0 : prevAtomState.d)) {
            mountDependencies(undefined, atom, atomState, prevAtomState == null ? void 0 : prevAtomState.d);
          }

          if (prevAtomState && !prevAtomState.y && atomState != null && atomState.y) {
            return;
          }

          var mounted = mountedMap.get(atom);
          mounted == null ? void 0 : mounted.l.forEach(function (listener) {
            return listener();
          });
        });
      }

      {
        stateListeners.forEach(function (l) {
          return l();
        });
      }
    };

    var commitVersionedAtomStateMap = function commitVersionedAtomStateMap(version) {
      var versionedAtomStateMap = getVersionedAtomStateMap(version);
      versionedAtomStateMap.forEach(function (atomState, atom) {
        var prevAtomState = committedAtomStateMap.get(atom);

        if (!prevAtomState || atomState.r > prevAtomState.r || atomState.y !== prevAtomState.y || atomState.r === prevAtomState.r && atomState.d !== prevAtomState.d) {
          committedAtomStateMap.set(atom, atomState);

          if (atomState.d !== (prevAtomState == null ? void 0 : prevAtomState.d)) {
            mountDependencies(version, atom, atomState, prevAtomState == null ? void 0 : prevAtomState.d);
          }
        }
      });
    };

    var commitAtom = function commitAtom(_atom, version) {
      if (version) {
        commitVersionedAtomStateMap(version);
      }

      flushPending(undefined);
    };

    var subscribeAtom = function subscribeAtom(atom, callback, version) {
      var mounted = addAtom(version, atom);
      var listeners = mounted.l;
      listeners.add(callback);
      return function () {
        listeners.delete(callback);
        delAtom(version, atom);
      };
    };

    var restoreAtoms = function restoreAtoms(values, version) {
      for (var _iterator2 = _createForOfIteratorHelperLoose(values), _step2; !(_step2 = _iterator2()).done;) {
        var _step2$value = _step2.value,
            _atom2 = _step2$value[0],
            _value = _step2$value[1];

        if (hasInitialValue(_atom2)) {
          setAtomPromiseOrValue(version, _atom2, _value);
          invalidateDependents(version, _atom2);
        }
      }

      flushPending(version);
    };

    {
      var _ref3;

      return _ref3 = {}, _ref3[READ_ATOM] = readAtom, _ref3[WRITE_ATOM] = writeAtom, _ref3[COMMIT_ATOM] = commitAtom, _ref3[SUBSCRIBE_ATOM] = subscribeAtom, _ref3[RESTORE_ATOMS] = restoreAtoms, _ref3[DEV_SUBSCRIBE_STATE] = function (l) {
        stateListeners.add(l);
        return function () {
          stateListeners.delete(l);
        };
      }, _ref3[DEV_GET_MOUNTED_ATOMS] = function () {
        return mountedAtoms.values();
      }, _ref3[DEV_GET_ATOM_STATE] = function (a) {
        return committedAtomStateMap.get(a);
      }, _ref3[DEV_GET_MOUNTED] = function (a) {
        return mountedMap.get(a);
      }, _ref3;
    }
  };
  var createStoreForExport = function createStoreForExport(initialValues) {
    var store = createStore(initialValues);

    var get = function get(atom) {
      var atomState = store[READ_ATOM](atom);

      if ('e' in atomState) {
        throw atomState.e;
      }

      if ('p' in atomState) {
        return undefined;
      }

      return atomState.v;
    };

    var asyncGet = function asyncGet(atom) {
      return new Promise(function (resolve, reject) {
        var atomState = store[READ_ATOM](atom);

        if ('e' in atomState) {
          reject(atomState.e);
        } else if ('p' in atomState) {
          resolve(atomState.p.then(function () {
            return asyncGet(atom);
          }));
        } else {
          resolve(atomState.v);
        }
      });
    };

    var set = function set(atom, update) {
      return store[WRITE_ATOM](atom, update);
    };

    var sub = function sub(atom, callback) {
      return store[SUBSCRIBE_ATOM](atom, callback);
    };

    return {
      get: get,
      asyncGet: asyncGet,
      set: set,
      sub: sub,
      SECRET_INTERNAL_store: store
    };
  };

  var createScopeContainer = function createScopeContainer(initialValues, unstable_createStore) {
    var store = unstable_createStore ? unstable_createStore(initialValues).SECRET_INTERNAL_store : createStore(initialValues);
    return {
      s: store
    };
  };
  var ScopeContextMap = new Map();
  var getScopeContext = function getScopeContext(scope) {
    if (!ScopeContextMap.has(scope)) {
      ScopeContextMap.set(scope, react.createContext(createScopeContainer()));
    }

    return ScopeContextMap.get(scope);
  };

  var Provider = function Provider(_ref) {
    var children = _ref.children,
        initialValues = _ref.initialValues,
        scope = _ref.scope,
        unstable_createStore = _ref.unstable_createStore,
        unstable_enableVersionedWrite = _ref.unstable_enableVersionedWrite;

    var _useState = react.useState({}),
        version = _useState[0],
        setVersion = _useState[1];

    react.useEffect(function () {
      var scopeContainer = scopeContainerRef.current;

      if (scopeContainer.w) {
        scopeContainer.s[COMMIT_ATOM](null, version);
        delete version.p;
        scopeContainer.v = version;
      }
    }, [version]);
    var scopeContainerRef = react.useRef();

    if (!scopeContainerRef.current) {
      var scopeContainer = createScopeContainer(initialValues, unstable_createStore);

      if (unstable_enableVersionedWrite) {
        var retrying = 0;

        scopeContainer.w = function (write) {
          setVersion(function (parentVersion) {
            var nextVersion = retrying ? parentVersion : {
              p: parentVersion
            };
            write(nextVersion);
            return nextVersion;
          });
        };

        scopeContainer.v = version;

        scopeContainer.r = function (fn) {
          ++retrying;
          fn();
          --retrying;
        };
      }

      scopeContainerRef.current = scopeContainer;
    }

    var ScopeContainerContext = getScopeContext(scope);
    return react.createElement(ScopeContainerContext.Provider, {
      value: scopeContainerRef.current
    }, children);
  };

  var keyCount = 0;
  function atom(read, write) {
    var key = "atom" + ++keyCount;
    var config = {
      toString: function toString() {
        return key;
      }
    };

    if (typeof read === 'function') {
      config.read = read;
    } else {
      config.init = read;

      config.read = function (get) {
        return get(config);
      };

      config.write = function (get, set, update) {
        return set(config, typeof update === 'function' ? update(get(config)) : update);
      };
    }

    if (write) {
      config.write = write;
    }

    return config;
  }

  function useAtomValue(atom, scope) {
    var ScopeContext = getScopeContext(scope);
    var scopeContainer = react.useContext(ScopeContext);
    var store = scopeContainer.s,
        versionFromProvider = scopeContainer.v;

    var getAtomValue = function getAtomValue(version) {
      var atomState = store[READ_ATOM](atom, version);

      if (!atomState.y) {
        throw new Error('should not be invalidated');
      }

      if ('e' in atomState) {
        throw atomState.e;
      }

      if ('p' in atomState) {
        throw atomState.p;
      }

      if ('v' in atomState) {
        return atomState.v;
      }

      throw new Error('no atom value');
    };

    var _useReducer = react.useReducer(function (prev, nextVersion) {
      var nextValue = getAtomValue(nextVersion);

      if (Object.is(prev[1], nextValue) && prev[2] === atom) {
        return prev;
      }

      return [nextVersion, nextValue, atom];
    }, versionFromProvider, function (initialVersion) {
      var initialValue = getAtomValue(initialVersion);
      return [initialVersion, initialValue, atom];
    }),
        _useReducer$ = _useReducer[0],
        version = _useReducer$[0],
        valueFromReducer = _useReducer$[1],
        atomFromReducer = _useReducer$[2],
        rerenderIfChanged = _useReducer[1];

    var value = valueFromReducer;

    if (atomFromReducer !== atom) {
      rerenderIfChanged(version);
      value = getAtomValue(version);
    }

    react.useEffect(function () {
      var versionFromProvider = scopeContainer.v;

      if (versionFromProvider) {
        store[COMMIT_ATOM](atom, versionFromProvider);
      }

      var unsubscribe = store[SUBSCRIBE_ATOM](atom, rerenderIfChanged, versionFromProvider);
      rerenderIfChanged(versionFromProvider);
      return unsubscribe;
    }, [store, atom, scopeContainer]);
    react.useEffect(function () {
      store[COMMIT_ATOM](atom, version);
    });
    react.useDebugValue(value);
    return value;
  }

  function useSetAtom(atom, scope) {
    var ScopeContext = getScopeContext(scope);

    var _useContext = react.useContext(ScopeContext),
        store = _useContext.s,
        versionedWrite = _useContext.w;

    var setAtom = react.useCallback(function (update) {
      if (!('write' in atom)) {
        throw new Error('not writable atom');
      }

      var write = function write(version) {
        return store[WRITE_ATOM](atom, update, version);
      };

      return versionedWrite ? versionedWrite(write) : write();
    }, [store, versionedWrite, atom]);
    return setAtom;
  }

  function useAtom(atom, scope) {
    if ('scope' in atom) {
      console.warn('atom.scope is deprecated. Please do useAtom(atom, scope) instead.');
      scope = atom.scope;
    }

    return [useAtomValue(atom, scope), useSetAtom(atom, scope)];
  }

  exports.Provider = Provider;
  exports.SECRET_INTERNAL_getScopeContext = getScopeContext;
  exports.SECRET_INTERNAL_registerPromiseAbort = registerPromiseAbort;
  exports.atom = atom;
  exports.unstable_createStore = createStoreForExport;
  exports.useAtom = useAtom;
  exports.useAtomValue = useAtomValue;
  exports.useSetAtom = useSetAtom;

  Object.defineProperty(exports, '__esModule', { value: true });

}));