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// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license."use strict";
((window) => {  const core = window.Deno.core;  const ops = core.ops;  const {    Set,    SymbolFor,    TypeError,  } = window.__bootstrap.primordials;
  function bindSignal(signo) {    return ops.op_signal_bind(signo);  }
  function pollSignal(rid) {    const promise = core.opAsync("op_signal_poll", rid);    core.unrefOp(promise[SymbolFor("Deno.core.internalPromiseId")]);    return promise;  }
  function unbindSignal(rid) {    ops.op_signal_unbind(rid);  }
  // Stores signal listeners and resource data. This has type of  // `Record<string, { rid: number | undefined, listeners: Set<() => void> }`  const signalData = {};
  /** Gets the signal handlers and resource data of the given signal */  function getSignalData(signo) {    return signalData[signo] ??      (signalData[signo] = { rid: undefined, listeners: new Set() });  }
  function checkSignalListenerType(listener) {    if (typeof listener !== "function") {      throw new TypeError(        `Signal listener must be a function. "${typeof listener}" is given.`,      );    }  }
  function addSignalListener(signo, listener) {    checkSignalListenerType(listener);
    const sigData = getSignalData(signo);    sigData.listeners.add(listener);
    if (!sigData.rid) {      // If signal resource doesn't exist, create it.      // The program starts listening to the signal      sigData.rid = bindSignal(signo);      loop(sigData);    }  }
  function removeSignalListener(signo, listener) {    checkSignalListenerType(listener);
    const sigData = getSignalData(signo);    sigData.listeners.delete(listener);
    if (sigData.listeners.size === 0 && sigData.rid) {      unbindSignal(sigData.rid);      sigData.rid = undefined;    }  }
  async function loop(sigData) {    while (sigData.rid) {      if (await pollSignal(sigData.rid)) {        return;      }      for (const listener of sigData.listeners) {        listener();      }    }  }
  window.__bootstrap.signals = {    addSignalListener,    removeSignalListener,  };})(this);