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const equalFn = (a, b) => a === b;const signalOptions = {  equals: equalFn};let ERROR = null;let runEffects = runQueue;const STALE = 1;const PENDING = 2;const UNOWNED = {  owned: null,  cleanups: null,  context: null,  owner: null};var Owner = null;let Listener = null;let Updates = null;let Effects = null;let ExecCount = 0;function createRoot(fn, detachedOwner) {  detachedOwner && (Owner = detachedOwner);  const listener = Listener,    owner = Owner,    root =      fn.length === 0 && !false        ? UNOWNED        : {            owned: null,            cleanups: null,            context: null,            owner          };  Owner = root;  Listener = null;  let result;  try {    runUpdates(() => (result = fn(() => cleanNode(root))), true);  } finally {    Listener = listener;    Owner = owner;  }  return result;}function createSignal(value, options) {  options = options ? Object.assign({}, signalOptions, options) : signalOptions;  const s = {    value,    observers: null,    observerSlots: null,    comparator: options.equals || undefined  };  return [    readSignal.bind(s),    value => {      if (typeof value === "function") {        value = value(s.value);      }      return writeSignal(s, value);    }  ];}function createComputed(fn, value) {  updateComputation(createComputation(fn, value, true, STALE));}function createMemo(fn, value, options) {  options = options ? Object.assign({}, signalOptions, options) : signalOptions;  const c = createComputation(fn, value, true, 0);  c.observers = null;  c.observerSlots = null;  c.comparator = options.equals || undefined;  updateComputation(c);  return readSignal.bind(c);}
function batch(fn) {  return runUpdates(fn, false);}function untrack(fn) {  let result,    listener = Listener;  Listener = null;  result = fn();  Listener = listener;  return result;}
function readSignal() {  if (this.state && this.sources) {    const updates = Updates;    Updates = null;    this.state === STALE ? updateComputation(this) : lookUpstream(this);    Updates = updates;  }  if (Listener) {    const sSlot = this.observers ? this.observers.length : 0;    if (!Listener.sources) {      Listener.sources = [this];      Listener.sourceSlots = [sSlot];    } else {      Listener.sources.push(this);      Listener.sourceSlots.push(sSlot);    }    if (!this.observers) {      this.observers = [Listener];      this.observerSlots = [Listener.sources.length - 1];    } else {      this.observers.push(Listener);      this.observerSlots.push(Listener.sources.length - 1);    }  }  return this.value;}function writeSignal(node, value, isComp) {  if (node.comparator) {    if (node.comparator(node.value, value)) return value;  }  node.value = value;  if (node.observers && node.observers.length) {    runUpdates(() => {      for (let i = 0; i < node.observers.length; i += 1) {        const o = node.observers[i];        if (!o.state) {          if (o.pure) Updates.push(o);          else Effects.push(o);          if (o.observers) markDownstream(o);        }        o.state = STALE;      }      if (Updates.length > 10e5) {        Updates = [];        throw new Error();      }    }, false);  }  return value;}function updateComputation(node) {  if (!node.fn) return;  cleanNode(node);  const owner = Owner,    listener = Listener,    time = ExecCount;  Listener = Owner = node;  runComputation(node, node.value, time);  Listener = listener;  Owner = owner;}function runComputation(node, value, time) {  let nextValue;  nextValue = node.fn(value);  if (!node.updatedAt || node.updatedAt <= time) {    if (node.updatedAt != null && "observers" in node) {      writeSignal(node, nextValue, true);    } else node.value = nextValue;    node.updatedAt = time;  }}function createComputation(fn, init, pure, state = STALE, options) {  const c = {    fn,    state: state,    updatedAt: null,    owned: null,    sources: null,    sourceSlots: null,    cleanups: null,    value: init,    owner: Owner,    context: null,    pure  };  if (Owner === null);  else if (Owner !== UNOWNED) {    if (!Owner.owned) Owner.owned = [c];    else Owner.owned.push(c);  }  return c;}function runTop(node) {  if (node.state === 0) return;  if (node.state === PENDING) return lookUpstream(node);  const ancestors = [node];  while ((node = node.owner) && (!node.updatedAt || node.updatedAt < ExecCount)) {    if (node.state) ancestors.push(node);  }  for (let i = ancestors.length - 1; i >= 0; i--) {    node = ancestors[i];    if (node.state === STALE) {      updateComputation(node);    } else if (node.state === PENDING) {      const updates = Updates;      Updates = null;      lookUpstream(node);      Updates = updates;    }  }}function runUpdates(fn, init) {  if (Updates) return fn();  let wait = false;  if (!init) Updates = [];  if (Effects) wait = true;  else Effects = [];  ExecCount++;  try {    const res = fn();    completeUpdates(wait);    return res;  } finally {    Updates = null;    if (!wait) Effects = null;  }}function completeUpdates(wait) {  if (Updates) {    runQueue(Updates);    Updates = null;  }  if (wait) return;  const e = Effects;  Effects = null;  if (e.length) runUpdates(() => runEffects(e), false);}function runQueue(queue) {  for (let i = 0; i < queue.length; i++) runTop(queue[i]);}function lookUpstream(node) {  node.state = 0;  for (let i = 0; i < node.sources.length; i += 1) {    const source = node.sources[i];    if (source.sources) {      if (source.state === STALE) runTop(source);      else if (source.state === PENDING) lookUpstream(source);    }  }}function markDownstream(node) {  for (let i = 0; i < node.observers.length; i += 1) {    const o = node.observers[i];    if (!o.state) {      o.state = PENDING;      if (o.pure) Updates.push(o);      else Effects.push(o);      o.observers && markDownstream(o);    }  }}function cleanNode(node) {  let i;  if (node.sources) {    while (node.sources.length) {      const source = node.sources.pop(),        index = node.sourceSlots.pop(),        obs = source.observers;      if (obs && obs.length) {        const n = obs.pop(),          s = source.observerSlots.pop();        if (index < obs.length) {          n.sourceSlots[s] = index;          obs[index] = n;          source.observerSlots[index] = s;        }      }    }  }  if (node.owned) {    for (i = 0; i < node.owned.length; i++) cleanNode(node.owned[i]);    node.owned = null;  }  if (node.cleanups) {    for (i = 0; i < node.cleanups.length; i++) node.cleanups[i]();    node.cleanups = null;  }  node.state = 0;  node.context = null;}exports.createComputed = createComputed;exports.createMemo = createMemo;exports.createRoot = createRoot;exports.createSignal = createSignal;exports.batch = batch;