@ciao-lang/ts-ciao-interface/dist/index.mjs.map

Simple Ciao interface for node.

{"version":3,"sources":["../src/core/js/ciao-prolog.js","../src/controllers/ciao-prolog-interface.ts","../src/controllers/interface-builder.ts","../src/assets/builder_functions.json"],"sourcesContent":["/*\n *  ciao-prolog.js\n *\n *  Main JavaScript interface to Ciao Prolog compiled to WebAssembly.\n *\n *  Copyright (C) 2017-2023 Jose F. Morales\n */\n\n/**\n   The JS interface for Ciao is implemented in several layers.  See\n   the documentation of the following classes/objects for more\n   information:\n\n   - `ToplevelProc`\n   - `CiaoWorker`\n   - `LLCiao`\n   - `CIAOENGINE`\n*/\n\n/* =========================================================================== */\n/**\n * `CiaoPromiseProxy`: promise object used to store and communicate\n * results from `CiaoWorker` when using a Web Worker.\n */\n\nclass CiaoPromiseProxy {\n  /* TODO: similar to (:- block) implementation */\n  /* TODO: 'reject' not supported */\n  /* TODO: Make sure that this passes the Promises tests suite: https://github.com/promises-aplus/promises-tests */\n  constructor() {\n    this.hasValue = false; /* has a value */\n    this.value = null; /* value */\n    this.handler = null; /* 'then' handler */\n    this.next = null; /* temporary promise, when the handler is not yet there */\n  }\n  setValue(value) {\n    if (typeof this.handler === 'function') { /* we have both handler and value, call */\n      var ret = this.handler(value);\n      if (typeof ret === 'undefined') {\n        this.next.setValue(undefined); /* no value */\n      } else {\n        if (typeof ret.then === 'function') { /* assume some Thenable (a promise) */\n          var this_next = this.next;\n          ret.then(function (r) {\n            this_next.setValue(r); /* propagate value */\n          });\n        } else {\n          this.next.setValue(ret); /* just value (equivalent to a promise coercion) */\n        }\n      }\n    } else { /* otherwise save the value */\n      this.value = value;\n      this.hasValue = true;\n    }\n  }\n  /* Note: assume that handler returns undefined or a promise */\n  then(handler) {\n    if (this.hasValue === true) { /* have both! call handler */\n      var ret = handler(this.value);\n      if (typeof ret.then === 'function') { /* assume some Thenable (a promise) */\n        return ret;\n      } else { /* promise coercion */\n        return CiaoPromiseProxy.resolve(ret);\n      }\n    } else { /* otherwise save the handler */\n      var next = new CiaoPromiseProxy(); /* create temporary promise */\n      this.next = next;\n      this.handler = handler;\n      return next;\n    }\n  }\n\n  /* A promise with resolved value `v` */\n  static resolve(v) {\n    var p = new CiaoPromiseProxy();\n    p.setValue(v);\n    return p;\n  }\n}\n\n/* =========================================================================== */\n/**\n * `LLCiao`: Low level interface for CIAOENGINE. It implements\n * environment setup, loading of bundle data.\n *\n * This function should not have any dependency with the parent\n * code. It can be executed directly or captured as a string to be\n * loaded as a Web Worker.\n */\n\nfunction new_LLCiao() {\n  var ENVIRONMENT_IS_WORKER = typeof importScripts === 'function';\n  var ENVIRONMENT_IS_NODE = typeof process == 'object' && typeof process.versions == 'object' && typeof process.versions.node == 'string';\n\n  if (ENVIRONMENT_IS_NODE) {\n    const fs = require('fs/promises');\n    const vm = require('vm');\n    var tryImportScript = async function (src) {\n      global.require = require; // TODO: why?\n      global.__dirname = __dirname; // TODO: why?\n      global.tryImportScript = tryImportScript; // TODO: why?\n      // TODO: better way?\n      var data = await fs.readFile(src);\n      // Note: emcc options \"-s NODEJS_CATCH_EXIT=0 -s\n      // NODEJS_CATCH_REJECTION=0\" are required to prevent nodejs from\n      // printing whole code on exceptions\n      vm.runInThisContext(data, { displayErrors: false, filename: src });\n    };\n    var tryFetchJSON = async function (src) {\n      var data = await fs.readFile(src);\n      return JSON.parse(data);\n    };\n  } else {\n    if (ENVIRONMENT_IS_WORKER) {\n      var tryImportScript = async function (src) {\n        importScripts(src); // async interface to importScripts from Web Worker\n      };\n    } else {\n      var tryImportScript = globalThis.tryImportScript;\n    }\n    var tryFetchJSON = async function (src) {\n      const response = await fetch(src);\n      return await response.json();\n    };\n  }\n\n  var EMCiao = {}; // Emscripten module for CIAOENGINE\n\n  var stdout = \"\";\n  var stderr = \"\";\n\n  var LLCiao = {};\n  LLCiao.emciao_initialized = false;\n  LLCiao.stats = {};   // Statistics\n  LLCiao.bundle = {};  // Bundle map\n  LLCiao.depends = []; // Bundle dependencies\n  LLCiao.root_URL = null; // URL for CIAOROOT (null when not initialized yet)\n\n  /* --------------------------------------------------------------------------- */\n\n  LLCiao.get_stats = function () { return LLCiao.stats; };\n\n  /* --------------------------------------------------------------------------- */\n\n  LLCiao.get_ciao_root = function () { return LLCiao.bundle['core'].wksp; };\n\n  function mkdir_noerr(path) {\n    let FS = LLCiao.getFS();\n    try { FS.mkdir(path); } catch (e) { /* ignore errors */ };\n  }\n\n  // Create directory path\n  function mkpath(path) {\n    var spath = path.split('/');\n    var len = spath.length;\n    var dir = \"\";\n    if (len > 0) {\n      dir += spath[0];\n      mkdir_noerr(dir);\n      for (var i = 1; i < len; i++) {\n        dir += \"/\" + spath[i];\n        mkdir_noerr(dir);\n      }\n    }\n  }\n\n  LLCiao.preload_file = function (dir, relpath) {\n    if (LLCiao.root_URL === null) throw new Error('null root_URL');\n    var srcurl = LLCiao.root_URL + relpath;\n    var srcdir = dir + '/' + relpath;\n    /* Split in dir and base */\n    var dirsplit = srcdir.split('/');\n    var base = dirsplit.pop();\n    var dir = dirsplit.join('/');\n    /* Create directory path for dir */\n    mkpath(dir);\n    /* Create preloaded file */\n    let FS = LLCiao.getFS();\n    //FS.createPreloadedFile(dir, base, srcurl, true, false);\n    FS.createPreloadedFile(dir, base, srcurl, true, true); // rw access\n    // TODO: only works in web workers, does not work in lpdoc example\n    // FS.createLazyFile(dir, base, srcurl, true, true); // rw access\n  };\n\n  async function maybeImportData(b_data, key) {\n    if (b_data.hasOwnProperty(key)) {\n      await tryImportScript(EMCiao.locateFile(b_data[key], ''));\n    }\n  }\n\n  LLCiao.preload_bundle = async function (b) {\n    // this loads *.mods.js\n    globalThis.__emciao = EMCiao;\n    const b_data = LLCiao.bundle[b];\n    if (b_data.hasOwnProperty('preload_files')) {\n      for (const rel_path of b_data.preload_files) {\n        LLCiao.preload_file(b_data.wksp, rel_path);\n      }\n    }\n    await Promise.all([maybeImportData(b_data, 'src_data'),\n    maybeImportData(b_data, 'mods_data')]);\n  };\n\n  LLCiao.collect_wksps = function () {\n    let wksps = [];\n    let seen = {};\n    for (const j of LLCiao.depends) {\n      var wksp = LLCiao.bundle[j].wksp;\n      if (!seen[wksp]) {\n        wksps.unshift(wksp); /* right order? */\n        seen[wksp] = true;\n      }\n    }\n    return wksps;\n  };\n\n  // Update timestamps of build/cache files\n  // TODO: needs around 8ms\n  // TODO: allow frozen workspaces in c_itf, inhibits recompilation!\n  // TODO: update needed for dynamic use_bundle?\n  LLCiao.update_timestamps = function (wksps) {\n    let FS = LLCiao.getFS();\n    var tsnow = Date.now();\n    for (const wksp of wksps) {\n      const dir = wksp + \"/build/cache\";\n      for (const f of FS.readdir(dir)) {\n        if (f.endsWith('.po') || f.endsWith('.itf')) {\n          const path = dir + \"/\" + f;\n          // const timestamp = FS.lookupPath(path).node.timestamp;\n          FS.utime(path, tsnow, tsnow);\n        }\n      }\n    }\n  };\n\n  // Mount a directory (only for NodeJS)\n  LLCiao.mount_dir = function (srcdir, dstdir) {\n    mkpath(dstdir);\n    var FS = LLCiao.getFS();\n    FS.mount(FS.filesystems.NODEFS, { root: srcdir }, dstdir);\n  };\n\n  // Pending loads\n  var pending_load = false;\n  var pending_load_resolve = undefined;\n\n  /* Suspend until all use_bundle has been completed */\n  LLCiao.wait_no_deps = function () {\n    return new Promise((resolve, reject) => { // TODO: 'reject' ignored\n      if (pending_load) {\n        if (pending_load_resolve !== undefined) { throw new Error('unresolved pending load'); };\n        pending_load_resolve = (function () { resolve(true); }); // called from monitor_deps when done\n      } else { /* there were no pending loads */\n        resolve(true);\n      }\n    });\n  };\n\n  function monitor_deps(numdeps) {\n    if (numdeps == 0) { // no more pending loads, notify if needed\n      if (pending_load_resolve !== undefined) {\n        pending_load_resolve();\n        pending_load_resolve = undefined;\n      }\n      pending_load = false; // no pending loads\n    }\n  }\n  LLCiao.use_bundle = async function (bundle) {\n    if (!ENVIRONMENT_IS_NODE) console.log(`{loading bundle '${bundle}'}`);\n    // Read and store .bundle.json metadata (see grade_wasm.pl)\n    const b_data = await tryFetchJSON(LLCiao.root_URL + \"build/dist/\" + bundle + \".bundle.json\");\n    if (!LLCiao.depends) LLCiao.depends = [];\n    LLCiao.depends.push(b_data.name);\n    LLCiao.bundle[b_data.name] = b_data;\n    // Initiate load if possible\n    if (LLCiao.emciao_initialized) { /* (preRun has already been called, preload here) */\n      pending_load = true; // at least one pending load\n      await LLCiao.preload_bundle(bundle);\n    }\n    return true;\n  }\n\n  /* --------------------------------------------------------------------------- */\n  /* Initialization */\n\n  /** \n   * `CIAOENGINE` is the Emscripten/WASM compiled engine (very low\n   * level). It is loaded dynamically from `eng` (e.g.,\n   * `ciaoengwasm`).\n   */\n\n  LLCiao.eng_load = async function (url, eng) {\n    LLCiao.root_URL = url;\n    /* Load CIAOENGINE (generated from emcc) */\n    if (!ENVIRONMENT_IS_NODE) console.log(`{loading engine '${eng}'}`);\n    await tryImportScript(LLCiao.root_URL + \"build/bin/\" + eng + \".js\");\n    return true;\n  };\n\n  LLCiao.init_emciao = function () {\n    return new Promise((resolve, reject) => { // TODO: 'reject' ignored\n      LLCiao.init_emciao_(resolve);\n    });\n  };\n  LLCiao.init_emciao_ = function (resolve) {\n    /* Start the engine with hooks for initialization */\n    EMCiao['locateFile'] = function (path, prefix) {\n      // custom dirs\n      let root_URL = LLCiao.root_URL;\n      if (root_URL === null) throw new Error('null root_URL');\n      if (path.endsWith(\".mem\")) return root_URL + \"build/bin/\" + path;\n      if (path.endsWith(\".wasm\")) return root_URL + \"build/bin/\" + path;\n      if (path.endsWith(\".src.data\")) return root_URL + \"build/dist/\" + path;\n      if (path.endsWith(\".src.js\")) return root_URL + \"build/dist/\" + path;\n      if (path.endsWith(\".mods.data\")) return root_URL + \"build/dist/\" + path;\n      if (path.endsWith(\".mods.js\")) return root_URL + \"build/dist/\" + path;\n      // otherwise, use the default, the prefix (JS file's dir) + the path\n      return prefix + path;\n    };\n    // Collect workspaces from dependencies\n    let wksps = LLCiao.collect_wksps();\n    // Capture stdout and stderr\n    EMCiao.print = function (out) {\n      stdout += out + \"\\n\";\n    };\n    EMCiao.printErr = function (err) {\n      stderr += err + \"\\n\";\n    };\n    // continue using code after run()\n    EMCiao.noExitRuntime = true;\n    // preRun (setup environment before run())\n    EMCiao.preRun = [];\n    EMCiao.preRun.push(function () {\n      // ('pre-js.js' intializes EMCiao['FS'] and EMCiao['getENV'])\n      // Monitor run dependencies\n      EMCiao['monitorRunDependencies'] = monitor_deps;\n      // Preload bundle files (if needed)\n      for (const b of LLCiao.depends) {\n        // annotate asynchronous preload_bundle termination as run dependencies for emscripten\n        var dep = \"preload bundle \" + b;\n        EMCiao['addRunDependency'](dep);\n        LLCiao.preload_bundle(b).then((result) => {\n          EMCiao['removeRunDependency'](dep);\n        });\n      }\n      // Preload bootfile so that it is accessible from the FS\n      LLCiao.preload_file(LLCiao.get_ciao_root(), \"build/bin/\" + LLCiao.bootfile); /* TODO: customize */\n      /* Set CIAOPATH from bundles */\n      (EMCiao.getENV())['CIAOPATH'] = wksps.join(\":\");\n    });\n    // \n    EMCiao.onRuntimeInitialized = function () {\n      LLCiao.update_timestamps(wksps);\n      //\n      var bootfile = LLCiao.get_ciao_root() + \"/build/bin/\" + LLCiao.bootfile;\n      let bootfile_ptr = EMCiao.stringToNewUTF8(bootfile);\n      EMCiao._ciaowasm_init(bootfile_ptr);\n      EMCiao._free(bootfile_ptr);\n      /* Boot the engine, which will execute main/0 and exit with a live runtime */\n      EMCiao._ciaowasm_boot();\n      /* (Continue) */\n      LLCiao.emciao_initialized = true;\n      resolve(null);\n    };\n    /* Begin execution of Emscripten (wasm) compiled engine */\n    if (!ENVIRONMENT_IS_NODE) console.log(`{booting engine}`);\n    globalThis.CIAOENGINE.run(EMCiao);\n  };\n\n  /* --------------------------------------------------------------------------- */\n\n  LLCiao.bootfile = 'ciaowasm';\n\n  /* Begin new query. See ciaowasm:query_one_fs/0 */\n  LLCiao.query_one_begin = function (goal) {\n    var query;\n    query = 'q((' + goal + ')).';\n    let FS = LLCiao.getFS();\n    FS.writeFile('/.q-i', query, { encoding: 'utf8' });\n    let q_ptr = EMCiao.stringToNewUTF8(\"ciaowasm:query_one_fs\");\n    EMCiao._ciaowasm_query_begin(q_ptr);\n    EMCiao._free(q_ptr);\n    return query_result();\n  };\n\n  /* Obtain next solution */\n  LLCiao.query_one_next = function () {\n    EMCiao._ciaowasm_query_next();\n    return query_result();\n  };\n\n  /* Resume query */\n  LLCiao.query_one_resume = function () {\n    EMCiao._ciaowasm_query_resume();\n    return query_result();\n  };\n\n  /* End query */\n  LLCiao.query_end = function () {\n    EMCiao._ciaowasm_query_end();\n  }\n\n  function recv_jscmd() {\n    let str;\n    let cmd;\n    let FS = LLCiao.getFS();\n    try {\n      str = FS.readFile('/.j-c', { encoding: 'utf8' });\n      FS.unlink('/.j-c');\n    } catch (err) {\n      return null;\n    }\n    return JSON.parse(str);\n  }\n\n  function query_result() {\n    let is_ok = EMCiao._ciaowasm_query_ok();\n    if (is_ok) {\n      let is_suspended = EMCiao._ciaowasm_query_suspended();\n      if (is_suspended) {\n        let cmd = recv_jscmd(); // null if none\n        // special case for debugger\n        if (cmd !== null && cmd.cmd === 'acall' && cmd.name === '$dbgtrace_get_line') {\n          return { cont: 'dbgtrace', arg: null };\n        }\n        return { cont: 'suspended', arg: cmd };\n      } else {\n        let FS = LLCiao.getFS();\n        let cont = FS.readFile('/.q-c', { encoding: 'utf8' });\n        let arg = FS.readFile('/.q-a', { encoding: 'utf8' });\n        return { cont: cont, arg: arg };\n      }\n    } else {\n      return { cont: 'failed', arg: '' };\n    }\n  }\n\n  /* --------------------------------------------------------------------------- */\n\n  /* Get Emscripten FS */\n  LLCiao.getFS = function () { return EMCiao['FS']; };\n\n  LLCiao.read_stdout = function () {\n    var out = stdout.replaceAll(\"\\n$$$fake_flush$$$\\n\", \"\"); /* TODO: see ciaowasm.pl for details about this horrible workaround */\n    stdout = \"\";\n    return out;\n  };\n  LLCiao.read_stderr = function () {\n    var err = stderr.replaceAll(\"\\n$$$fake_flush$$$\\n\", \"\"); /* TODO: see ciaowasm.pl for details about this horrible workaround */\n    stderr = \"\";\n    return err;\n  };\n\n  LLCiao.writeFile = function (a, b) {\n    try {\n      return LLCiao.getFS().writeFile(a, b, { encoding: 'utf8' });\n    } catch (err) {\n      return null;\n    }\n  };\n  LLCiao.readFile = function (a) {\n    try {\n      return LLCiao.getFS().readFile(a, { encoding: 'utf8' });\n    } catch (err) {\n      return null;\n    }\n  };\n\n  /* --------------------------------------------------------------------------- */\n\n  LLCiao.send_jsret = function (x) {\n    if (x === undefined) return true;\n    try {\n      let str = JSON.stringify(x);\n      return LLCiao.getFS().writeFile('/.j-o', str, { encoding: 'utf8' });\n    } catch (err) {\n      return null;\n    }\n  }\n\n  // sync\n  var f = {};\n  f['get_stats'] = true;\n  f['get_ciao_root'] = true;\n  f['writeFile'] = true;\n  f['readFile'] = true;\n  f['read_stdout'] = true;\n  f['read_stderr'] = true;\n  f['send_jsret'] = true;\n  f['query_one_begin'] = true;\n  f['query_one_resume'] = true;\n  f['query_one_next'] = true;\n  f['query_end'] = true;\n  // async\n  var af = {};\n  af['eng_load'] = true;\n  af['init_emciao'] = true;\n  af['wait_no_deps'] = true;\n  af['use_bundle'] = true;\n\n  LLCiao.run_cmd = async function (cmd, args) {\n    if (af.hasOwnProperty(cmd)) { // async\n      return LLCiao[cmd].apply(undefined, args);\n    } else if (f.hasOwnProperty(cmd)) { // sync\n      return new Promise((resolve, reject) => { // TODO: 'reject' ignored\n        resolve(LLCiao[cmd].apply(undefined, args));\n      });\n    } else {\n      throw new Error(\"unknown cmd \" + cmd);\n    }\n  };\n\n  /* --------------------------------------------------------------------------- */\n\n  return LLCiao;\n}\n\n// TODO: make Web Worker optional\nfunction ciao_worker_fun() {\n  var __ciao = new_LLCiao();\n  this.onmessage = function (event) {\n    var resolve = (function (x) { postMessage({ id: event.data.id, ret: x }); });\n    __ciao.run_cmd(event.data.cmd, event.data.args).then(resolve);\n  };\n  /* connect with browser console */\n  console = self.console; /* TODO: keep only in debug? */\n}\n// Note: use data-URI as an alternative \"data:application/x-javascript;base64,\"+...\nfunction ciao_worker_url() {\n  let code = new_LLCiao.toString();\n  let worker_code = ciao_worker_fun.toString();\n  worker_code = worker_code.slice(worker_code.indexOf(\"{\") + 1, worker_code.lastIndexOf(\"}\"));\n  code += \"\\n\" + worker_code; // get body (vars need to be global)\n  const blob = new Blob([code], { type: 'text/javascript' });\n  return URL.createObjectURL(blob);\n}\n\n/* =========================================================================== */\n\n//var use_webworker = false;\nvar use_webworker = true;\n\n/**\n * `CiaoWorker`: High level interface, schedules JS<->Prolog\n * interaction, has (optional) Web Worker support (CiaoPromiseProxy).\n */\nclass CiaoWorker {\n  constructor(root_URL) {\n    this.eng_loaded = false;\n    this.eng_booted = false;\n    this.root_URL = root_URL;\n    //\n    if (use_webworker) {\n      var listeners = [];\n      this.listeners = listeners;\n      this.w = new Worker(ciao_worker_url());\n      this.w.onmessage = function (event) {\n        listeners[event.data.id].setValue(event.data.ret);\n        delete listeners[event.data.id]; /* undefine this array element */\n      };\n    } else {\n      this.llciao = new_LLCiao();\n    }\n  }\n\n  /**\n   * Perform a request to `this.w` (the worker running the Ciao\n   * engine). It creates and returns a CiaoPromiseProxy, whose value\n   * is set on completion.\n   */\n  #async_(cmd, args) {\n    if (use_webworker) {\n      var proxy = new CiaoPromiseProxy();\n      /* set in listeners (get next free id or push) */\n      var id = 0;\n      for (var id = 0; id < this.listeners.length; id++) {\n        if (this.listeners[id] === undefined) break;\n      }\n      if (id === this.listeners.length) {\n        this.listeners.push(proxy);\n      } else {\n        this.listeners[id] = proxy;\n      }\n      this.w.postMessage({\n        id: id, /* id of message in listener array */\n        cmd: cmd,\n        args: args\n      });\n      return proxy;\n    } else {\n      return this.llciao.run_cmd(cmd, args);\n    }\n  }\n\n  /**\n   * Ensure that Ciao is initialized. Level can be:\n   *   1: engine loaded\n   *   2: engine loaded and booted\n   */\n  async ensure_init(level) {\n    if (this.pending_level >= level) return;\n    this.pending_level = level;\n    if (level >= 1 && !this.eng_loaded) {\n      this.eng_loaded = true;\n      var url = this.root_URL;\n      // (hack to get absolute url)\n      if (use_webworker) {\n        let a = document.createElement('a');\n        a.href = url;\n        url = a.href; // TODO: needs to be absolute due to importScripts from Web Worker\n      }\n      await this.#async_('eng_load', [url, \"ciaoengwasm\"]);\n    }\n    if (level >= 2 && !this.eng_booted) {\n      this.eng_booted = true;\n      await this.#async_('init_emciao', []);\n    }\n  }\n\n  /**\n   * Use the bundle passed as a parameter, loading the engine if needed.\n   * @param {string} name - Name of the bundle. \n   */\n  async use_bundle(name) {\n    await this.ensure_init(1);\n    return await this.#async_('use_bundle', [name]);\n  };\n\n  async wait_no_deps() {\n    await this.ensure_init(1);\n    return await this.#async_('wait_no_deps', []);\n  }\n\n  /**\n   * Get the stats of the latest call.\n   */\n  async get_stats() {\n    await this.ensure_init(1);\n    return await this.#async_('get_stats', []);\n  };\n\n  /**\n   * Get the Ciao root path.\n   */\n  async get_ciao_root() {\n    await this.ensure_init(1);\n    return await this.#async_('get_ciao_root', []);\n  };\n\n  /**\n   * Begins the query passed as parameter and obtains one solution. The\n   * decision tree stays awake and waits for user's input.\n   * @param {string} goal - Query to be launched.\n   */\n  async query_one_begin(goal) {\n    console.log('Query sent: ', goal);\n    await this.ensure_init(2);\n    let q_out = await this.#async_('query_one_begin', [goal]);\n    return await this.#query_complete(q_out);\n  }\n\n  /**\n   * Obtain the next solution for the query previously launched.\n   */\n  async query_one_next() {\n    let q_out = await this.#async_('query_one_next', []);\n    return await this.#query_complete(q_out);\n  }\n\n  /** Resume query until completed (not suspended). Process jscmd if needed\n   */\n  async #query_complete(q_out) {\n    while (q_out.cont === 'suspended') {\n      let cmd = q_out.arg;\n      if (cmd !== null) { /* run cmd if needed */\n        let ret = await jscmd_run(this, cmd);\n        await this.#async_('send_jsret', [ret]);\n      }\n      q_out = await this.#async_('query_one_resume', []);\n    }\n    return q_out;\n  }\n\n  /** Resume a query suspended in dbgtrace\n   */\n  async query_resume_dbgtrace(dbgcmd) {\n    /* pre: previous q_out.cont === 'dbgtrace' */\n    await this.#async_('send_jsret', [dbgcmd]);\n    let q_out = await this.#async_('query_one_resume', []);\n    return await this.#query_complete(q_out);\n  }\n\n  /**\n   * End the query.\n   */\n  async query_end() { return await this.#async_('query_end', []); }\n\n  /**\n   * Read file specified in path parameter.\n   * @param {string} path - Path of the file to read.\n   */\n  async readFile(path) {\n    await this.ensure_init(2);\n    return await this.#async_('readFile', [path]);\n  };\n\n  /**\n   * Write a string in a file.\n   * @param {string} path - Path of the file to write.\n   * @param {string} contents - String of the contents to write in the file.\n   */\n  async writeFile(path, contents) {\n    await this.ensure_init(2);\n    return await this.#async_('writeFile', [path, contents]);\n  };\n\n  /**\n   * Capture the stdout of the most recent query.\n   */\n  async read_stdout() { return await this.#async_('read_stdout', []); };\n\n  /**\n   * Capture the stderr of the most recent query.\n   */\n  async read_stderr() { return await this.#async_('read_stderr', []); };\n\n  /**\n   * Terminate the worker `w`\n   */\n  terminate() {\n    if (use_webworker) {\n      return this.w.terminate();\n    } else {\n      throw new Error('terminate needs Web Worker');\n    }\n  }\n}\n\n/* =========================================================================== */\n/* JS reference table */\n\n// This table is used to assign unique indices to JS objects passed to\n// a CiaoWorker.\n//\n// TODO:\n//  - indices are reused but the heap table is not compacted\n//  - use 'externref' [1] to simplify gluecode? (does it work from\n//    workers?)\n//  - foreign GC needed to do jsref_free automatically\n//\n// [1] https://github.com/WebAssembly/reference-types/blob/master/proposals/reference-types/Overview.md\n\n/* The index->obj table (global and shared) */\nvar jsref_heap = []; // index->obj table\nvar jsref_freeidx = []; // free indices in the heap table (holes)\n\n// Allocate a slot for `obj` and return its index\nfunction jsref_alloc(obj) {\n  if (jsref_freeidx.length != 0) { // reuse a free idx\n    let idx = jsref_freeidx.pop();\n    jsref_heap[idx] = obj;\n    return idx;\n  } else { // alloc a new idx\n    return jsref_heap.push(obj) - 1; // index\n  }\n}\n\n// Free the slot `idx`\nfunction jsref_free(idx) {\n  jsref_freeidx.push(idx); // add to the free pool\n  jsref_heap[idx] = null; // remove\n}\n\nfunction jsref_obj(idx) {\n  return jsref_heap[idx];\n}\n\n/* =========================================================================== */\n/* JS command buffer */\n\n// JS command buffer is a JSON encoded list of commands.\n//  \n// Instructions are objects such that:\n//\n//   i.cmd==\"def\": assigns code i.code for function i.name at jscmd_f\n//   i.cmd==\"call\": call function i.name with arguments i.args\n//   i.cmd==\"acall\": await call function i.name with arguments i.args\n\n// TODO: simplify this part using reference types\n//   https://github.com/WebAssembly/reference-types/blob/master/proposals/reference-types/Overview.md\n\n/* JS function table (global and shared) */\nvar jscmd_f = {};\n\n/* Execute jscmd */\nasync function jscmd_run(w, jscmd) {\n  let ret;\n  switch (jscmd.cmd) {\n    case 'def': /* define function */\n      jscmd_f[jscmd.name] = Function('\"use strict\";return (' + jscmd.code + ')')();\n      return null; /* TODO: provide id? */\n    case 'call':\n      jscmd.args.unshift(w); // worker as 1st argument\n      return jscmd_f[jscmd.name].apply(undefined, jscmd.args);\n    case 'acall':\n      jscmd.args.unshift(w); // worker as 1st argument\n      return await jscmd_f[jscmd.name].apply(undefined, jscmd.args);\n    default:\n      console.log('error: unknown jscmd: ' + jscmd);\n  }\n}\n\n/* =========================================================================== */\n/**\n * `ToplevelProc`: toplevel (REPL) process\n */\n\n// TODO: move more code to Prolog (this reimplements part of\n//   toplevel.pl due to problems with blocking IO in\n//   WASM/JS). Suspendable IO on wasm level would allow sharing more\n//   code here.\n\nconst toplevelCfg_defaults = {\n  // Show statistics (and some logging info) per query (in the JS console)\n  statistics: true,\n  // Query timeout (seconds) (0 to disable)\n  query_timeout: 200,\n  // Special queries // TODO: missing arity\n  special_query: {\n    \"use_module\": { read_code: true, mark_errs: true },\n    \"run_tests_in_module\": {\n      read_code: true,\n      mark_errs: true,\n      depends: ['ciaodbg'],\n      on_init: [\"use_module(library(unittest))\"]\n    },\n    //    \"clean_mods\": {\n    //      on_init: ['use_module(ciaobld(ciaoc_batch_call), [clean_mods/1])']\n    //    },\n    \"doc_cmd\": {\n      read_code: true,\n      mark_errs: true,\n      depends: ['lpdoc'],\n      on_init: ['use_module(lpdoc(docmaker))']\n    },\n    //\n    \"set_menu_flag\": { // arity {3}\n      read_code: false,\n      mark_errs: false,\n      depends: ['ciaopp', 'typeslib'],\n      on_init: [\"use_module(ciaopp(ciaopp))\"]\n    },\n    \"module\": {\n      read_code: true,\n      mark_errs: true,\n      depends: ['ciaopp', 'typeslib'],\n      on_init: [\"use_module(ciaopp(ciaopp))\"]\n    },\n    \"auto_analyze\": { // arity {1,2}\n      read_code: true,\n      mark_errs: true,\n      depends: ['ciaopp', 'typeslib'],\n      on_init: [\"use_module(ciaopp(ciaopp))\"]\n    },\n    \"auto_optimize\": { // arity {1,2}\n      read_code: true,\n      mark_errs: true,\n      depends: ['ciaopp', 'typeslib'],\n      on_init: [\"use_module(ciaopp(ciaopp))\"]\n    },\n    \"auto_check_assert\": { // arity {1,2}\n      read_code: true,\n      mark_errs: true,\n      depends: ['ciaopp', 'typeslib'],\n      on_init: [\"use_module(ciaopp(ciaopp))\"]\n    },\n    \"filter_analyze\": { // arity {1,2}\n      read_code: true,\n      mark_errs: true,\n      depends: ['ciaopp', 'typeslib', 'exfilter'],\n      on_init: [\"use_module(exfilter(exfilter))\"]\n    },\n    \"filter_analyze_exercise_mode\": { // arity {1,2}\n      read_code: true,\n      mark_errs: true,\n      depends: ['ciaopp', 'typeslib', 'exfilter'],\n      on_init: [\"use_module(exfilter(exfilter))\"]\n    }\n  },\n  // Default bundles and initialization queries\n  init_bundles: [\n    'ciaowasm', // (for foreign-js)\n    'core',\n    'builder'\n  ],\n  init_queries: [\n    'use_module(engine(internals), [reload_bundleregs/0])',\n    'use_module(library(classic/classic_predicates))'\n  ],\n  // Query for loading code\n  //   toplevelCfg.custom_load_query = ((m) => ...);\n  // Transformation for user queries\n  //   toplevelCfg.custom_run_query = ((q) => ... );\n  // Post-print code (before update_inner_layout()) \n  //   toplevelCfg.custom_postprint_sol = (async (pg) => ...);\n};\n\nif (typeof toplevelCfg === 'undefined') { var toplevelCfg = {}; }\ntoplevelCfg = Object.assign({ ...toplevelCfg_defaults }, toplevelCfg);\n\nvar QueryState = {\n  READY: 0, // ready for a query\n  RUNNING: 1, // query running\n  VALIDATING: 2, // prompt waiting for validating solution\n  DBGTRACE: 3 // prompt in a debugging state\n};\n\nclass ToplevelProc {\n  constructor(root_URL) {\n    this.root_URL = root_URL;\n    this.w = null;\n    this.comint = null; // associated comint ('null' to ignore)\n    this.muted = false; // temporarily ignore comint // TODO: change comint instead?\n    this.state = null;\n    this.q_opts = {}; // running/validating query opts\n    this.timer = undefined;\n  }\n\n  /* ---------------------------------------------------------------------- */\n\n  /* Is the worker started? */\n  is_started() {\n    return (this.w !== null);\n  }\n\n  /* Start the worker (and load defaults, show prompt, load program) */\n  async start() {\n    if (!this.muted) this.comint.set_log('Loading bundles and booting');\n    this.w = new CiaoWorker(this.root_URL); // create a Ciao worker\n    await this.load_ciao_defaults(); // TODO: check result?\n    if (!this.muted) this.comint.set_log('');\n    //\n    this.update_state(QueryState.READY);\n    this.q_opts = {};\n    if (!this.muted) this.comint.display_status_new_prompt('silent');\n    await this.comint.pg.on_cproc_start();\n  }\n\n  /* Restart the worker */\n  async restart() {\n    this.shutdown();\n    this.update_state(QueryState.READY);\n    this.q_opts = {};\n    const pmuted = this.set_muted(true); // TODO: mute on restart, make it optional?\n    await this.start();\n    this.muted = pmuted;\n  }\n\n  /* Terminate worker */\n  shutdown() {\n    if (!this.is_started()) return;\n    this.w.terminate();\n    this.w = null;\n  }\n\n  /* Make sure that worker is started */\n  async ensure_started(comint) {\n    if (this.is_started()) return;\n    this.comint = comint; // attach to this comint\n    await this.start();\n  }\n\n  // set muted and return previous value\n  set_muted(v) {\n    const prev = this.muted;\n    this.muted = v;\n    return prev;\n  }\n\n  /* ---------------------------------------------------------------------- */\n\n  // Load the default bundles and modules\n  async load_ciao_defaults() {\n    // Use default bundles and show boot info (this starts the engine)\n    for (const b of toplevelCfg.init_bundles) {\n      await this.w.use_bundle(b);\n    }\n    // // TODO: parallel load does not speed up load\n    // await Promise.all(toplevelCfg.init_bundles.map(async (b) => { await this.w.use_bundle(b); }));\n    // Boot and show system info\n    {\n      this.w.curr_cproc = this; // TODO: simplify\n      await this.w.query_one_begin(\"'$:'('internals:$bootversion')\"); // TODO: check errors!\n      let out = await this.w.read_stdout();\n      let err = await this.w.read_stderr();\n      await this.w.query_end();\n      this.comint.pg.show_version(out + err);\n    }\n    // Initialization queries on the toplevel\n    for (const q of toplevelCfg.init_queries) {\n      await this.muted_query_dumpout(q);\n    }\n    return true;\n  }\n\n  // Add (and execute) a new initialization query \n  async push_on_init(qs) {\n    const started = this.is_started();\n    for (const q of qs) {\n      if (!toplevelCfg.init_queries.includes(q)) {\n        toplevelCfg.init_queries.push(q);\n        if (started) await this.muted_query_dumpout(q);\n      }\n    }\n  }\n\n  // Add (and load) a new bundle dependency\n  async push_depends(bs) {\n    let updated = false;\n    const started = this.is_started();\n    for (const b of bs) {\n      if (!toplevelCfg.init_bundles.includes(b)) {\n        toplevelCfg.init_bundles.push(b);\n        if (started) await this.w.use_bundle(b); // load if already started\n        updated = true;\n      }\n    }\n    // if (started && updated) await this.restart(); // TODO: not needed now!\n    if (started && updated) {\n      await this.w.wait_no_deps(); /* wait until there are no pending loading deps */\n      await this.muted_query_dumpout('reload_bundleregs');\n    }\n  }\n\n  /* ---------------------------------------------------------------------- */\n\n  // Do a query, only one solution, dump stdout/stderr, \n  async muted_query_dumpout(q) {\n    if (toplevelCfg.statistics) console.log(`{implicit: ${q}}`);\n    this.w.curr_cproc = this; // TODO: simplify\n    await this.w.query_one_begin(q);\n    await this.dumpout(); // TODO: check errors!\n    await this.w.query_end();\n  }\n\n  // Dump last query stdout/stderr (ignore or show in console)\n  async dumpout() {\n    let out = await this.w.read_stdout();\n    let err = await this.w.read_stderr();\n    if (toplevelCfg.statistics) console.log(out + err);\n  }\n\n  /* ---------------------------------------------------------------------- */\n\n  set_query_timeout() {\n    if (toplevelCfg.query_timeout == 0) return; /* no timeout */\n    this.timer = setTimeout((async () => {\n      if (!this.muted) this.comint.print_msg('\\n{ABORTED: Time limit exceeded.}\\n');\n      await this.restart();\n      if (!this.muted) this.comint.display_status_new_prompt('silent'); /* amend prompt if needed */\n    }), toplevelCfg.query_timeout * 1000); /* set a timeout */\n  }\n  cancel_query_timeout() {\n    if (this.timer !== undefined) {\n      clearTimeout(this.timer);\n      this.timer = undefined;\n    }\n  }\n\n  /* ---------------------------------------------------------------------- */\n\n  // TODO: only works for single goal queries; this needs to be done\n  // at Prolog level with Prolog->JS communication\n\n  async trans_query(query) {\n    let treat_outerr = null;\n    // apply transformation if needed\n    if (toplevelCfg.custom_run_query !== undefined) {\n      query = toplevelCfg.custom_run_query(query);\n    }\n    // perform special query actions\n    let f_match = query.match(/([a-z][_a-zA-Z0-9]*)(?:\\(|$)/); // functor name // TODO: arity is missing, do from Prolog\n    if (f_match != null && f_match.length == 2) {\n      const special_query = toplevelCfg.special_query[f_match[1]];\n      if (special_query !== undefined) {\n        if (special_query.depends !== undefined) { // new (bundle) dependencies\n          await this.push_depends(special_query.depends);\n        }\n        if (special_query.on_init !== undefined) { // new initialization queries\n          await this.push_on_init(special_query.on_init);\n        }\n        if (special_query.read_code === true) { // the query may read the code, upload to worker\n          await this.comint.pg.upload_code_to_worker();\n        }\n        if (special_query.action !== undefined) { // replace auto_action\n          this.comint.pg.set_auto_action(special_query.action);\n        }\n        if (special_query.mark_errs === true) { // the query may show messages on the code, treat outerr\n          treat_outerr = async (out, err) => {\n            this.comint.pg.mark_errs(out, err); // TODO: missing matching file?\n          };\n        }\n      }\n    }\n    //\n    return { q: query, treat_outerr: treat_outerr };\n  }\n\n  /* ---------------------------------------------------------------------- */\n\n  update_state(state) {\n    this.state = state;\n    this.comint.update_inner_layout(); // (query state changed)\n  }\n\n  /* Alert if we are still running */\n  check_not_running() {\n    if (this.state === QueryState.RUNNING) {\n      alert('Already running a query');\n      return false;\n    }\n    return true;\n  }\n  /* Alert if we are locked validating/debugging in another comint */\n  check_not_locked(comint) {\n    if (this.comint !== comint) {\n      alert('Already validating/debugging a query in other comint');\n      return false;\n    }\n    return true;\n  }\n  /* Waiting for a line (validating query or debugging state) */\n  is_waiting_for_line() {\n    return (this.state === QueryState.VALIDATING || this.state === QueryState.DBGTRACE);\n  }\n\n  /**\n   * Execute a new query on the toplevel (Pre: this.state === QueryState.READY)\n   * @param {string} query - Query to be executed.\n   */\n  async run_query(comint, query, opts) {\n    if (this.state !== QueryState.READY) {\n      console.log('bug: already running or validating a query'); // TODO: treat_enter too fast?\n      return; // TODO: query is lost!\n    }\n    this.comint = comint; // attach to this comint\n    // ----\n    let tr = await this.trans_query(query);\n    query = tr.q;\n    // TODO: almost duplicated\n    this.update_state(QueryState.RUNNING);\n    this.q_opts = opts;\n    // begin a new query\n    if (!this.muted && opts.msg !== undefined) this.comint.set_log(opts.msg);\n    this.set_query_timeout();\n    this.w.curr_cproc = this; // TODO: simplify\n    let q_out = await this.w.query_one_begin(query);\n    this.cancel_query_timeout();\n    if (!this.muted && opts.msg !== undefined) this.comint.set_log('');\n    //\n    await this.treat_sol(q_out, tr.treat_outerr); // treat query result\n  }\n\n  /**\n   * Send a line command (`action`). This is used to validate\n   * solutions (if this.state === QueryState.VALIDATING) or send a\n   * debugger command (if this.state === QueryState.DBGTRACE)\n   */\n  async send_line(comint, action) {\n    this.comint = comint; // attach to this comint\n    if (this.state === QueryState.VALIDATING) {\n      if (action === '') { // accept solution, end query\n        this.w.curr_cproc = this; // TODO: simplify\n        await this.w.query_end();\n        this.update_state(QueryState.READY);\n        this.q_opts = {};\n        /*if (!this.muted)*/ this.comint.display_status_new_prompt('yes');\n      } else { // ask for the next solution\n        // TODO: almost duplicated\n        this.update_state(QueryState.RUNNING);\n        // next query solution\n        this.set_query_timeout();\n        this.w.curr_cproc = this; // TODO: simplify\n        let q_out = await this.w.query_one_next();\n        this.cancel_query_timeout();\n        //\n        await this.treat_sol(q_out, null); // treat query result\n      }\n    } else if (this.state === QueryState.DBGTRACE) {\n      this.update_state(QueryState.RUNNING);\n      // continue execution\n      this.set_query_timeout();\n      this.w.curr_cproc = this; // TODO: simplify\n      let q_out = await this.w.query_resume_dbgtrace(action);\n      this.cancel_query_timeout();\n      //\n      await this.treat_sol(q_out, null); // treat query result\n    } else {\n      console.log('bug: not in a validating/debugging solution state'); // TODO: treat_enter too fast?\n    }\n  }\n\n  /**\n   * If current query has a solution, print it and asks for more if\n   * there are more solutions available. If it has no solutions, finish\n   * the query.\n   * @param {Object} q_out - Object containing an array with the solution of a query.\n   */\n\n  async treat_sol(q_out, treat_outerr) {\n    let out = await this.w.read_stdout();\n    let err = await this.w.read_stderr();\n    /* print stdout and stderr output */\n    if (!this.muted) this.comint.print_out(out + err);\n    /* special case for debugger */\n    if (q_out.cont === 'dbgtrace') { // TODO: better way?\n      this.update_state(QueryState.DBGTRACE);\n      return;\n    }\n    /* print solution */\n    let solstatus;\n    if (q_out.cont === 'failed') { // no more solutions\n      solstatus = 'no';\n    } else {\n      // TODO: fixme, see toplevel.pl\n      /* Pretty print query results (solutions or errors) */\n      // (see ciaowasm.pl for possible cases)\n      if (q_out.cont === 'success') {\n        if (this.comint.with_prompt) { /* only if itr, otherwise ignore bindings and cut */\n          let prettysol = q_out.arg;\n          if (prettysol === '') { // (no bindings, cut)\n            solstatus = 'yes';\n          } else {\n            solstatus = '?'; // TODO: not always! detect when there are no choicepoints\n            if (!this.muted) this.comint.print_sol(prettysol); // print solution\n          }\n        }\n      } else if (q_out.cont === 'exception') { // TODO: horrible hack\n        let ball = q_out.arg;\n        if (!this.muted) this.comint.print_msg(`{ERROR: No handle found for thrown exception ${ball}}\\n`);\n        solstatus = 'aborted';\n      } else if (q_out.cont === 'malformed') {\n        solstatus = 'silent';\n        if (!this.muted) this.comint.print_msg('{SYNTAX ERROR: Malformed query}\\n');\n      } else {\n        solstatus = 'silent';\n        console.log(`bug: unrecognized query result cont: ${q_out.cont} ${q_out.arg}`);\n      }\n    }\n    const no_treat_outerr = this.q_opts.no_treat_outerr;\n    if (solstatus === '?') {\n      this.update_state(QueryState.VALIDATING);\n      if (!this.muted) this.comint.print_promptval();\n    } else {\n      await this.w.query_end();\n      this.update_state(QueryState.READY);\n      this.q_opts = {};\n      if (!this.muted) this.comint.display_status_new_prompt(solstatus);\n    }\n    if (treat_outerr !== null) {\n      if (no_treat_outerr !== true) {\n        await treat_outerr(out, err);\n      }\n    } else if (!this.muted) {\n      if (toplevelCfg.custom_postprint_sol !== undefined) {\n        // custom postprint if needed\n        await toplevelCfg.custom_postprint_sol(this.comint.pg);\n      }\n    }\n  }\n\n  /* ---------------------------------------------------------------------- */\n\n  /**\n   * Abort the execution of the current query (if inside of `run_query(query)`).\n   */\n  async abort() {\n    if (this.state === QueryState.RUNNING) {\n      this.cancel_query_timeout();\n      // print message\n      // if (!this.muted) this.comint.print_msg('\\n{ Execution aborted }\\n'); // (same text as Ciao)\n      if (!this.muted) this.comint.print_msg('\\n{ Execution aborted (resetting dynamic database) }\\n'); // TODO: remove note when preserving the database is working\n      // restart worker and update variables\n      // TODO: just abort query, not the worker\n      await this.restart();\n      if (!this.muted) this.comint.display_status_new_prompt('silent'); /* amend prompt if needed */\n    }\n  }\n}\n\n/* =========================================================================== */\n/**\n * Toplevel for execution under NodeJS\n */\n\n// TODO: with_prompt is not configurable yet\n// TODO: exit code is not returned\n\nvar ENVIRONMENT_IS_NODE = typeof process == 'object' && typeof process.versions == 'object' && typeof process.versions.node == 'string';\n\nif (ENVIRONMENT_IS_NODE) {\n  const path = require('path');\n  const process = require('process');\n\n  const printout = function (x) { process.stdout.write(x); };\n\n  // Locate site path relative to the script dir\n  var site_path = path.join(__dirname, '..');\n\n  // Simpler PGCell for RLComint\n  class RLPGCell {\n    constructor(cproc) {\n      this.cproc = cproc;\n    }\n    async setup(rl) {\n      // readline-based comint\n      this.comint = new RLComint(rl, this, {});\n      // start\n      await this.cproc.ensure_started(this.comint);\n    }\n    async on_cproc_start() {\n    }\n    show_version(str) {\n      this.cproc.comint.display(str);\n    }\n    async upload_code_to_worker() {\n    }\n    mark_errs(out, err) {\n    }\n    /* mark source debug info */\n    mark_srcdbg_info(info) {\n      this.comint.display(`         In ${info.src} (${info.ln0}-${info.ln1}) ${info.pred}-${info.num}\\n`);\n    }\n  }\n\n  class RLComint {\n    constructor(rl, pg, opts) {\n      this.prompt = '?- ';\n      this.promptval = ' ? ';\n\n      this.with_prompt = (opts.noprompt === true ? false : true); // interactive\n      this.pg = pg; // associated pgcell\n\n      this.rl = rl; // readline\n      this.next_prompt = ''; // prompt to be displayed (may contain solution)\n    }\n\n    update_inner_layout() { }\n    display(text) { process.stdout.write(text); }\n\n    print_out(str) { this.display(str); }\n    print_sol(str) { this.next_prompt = \"\\n\" + str; }\n    print_msg(str) { this.display(str); }\n\n    print_prompt() {\n      if (!this.with_prompt) return; /* (skip in non-interactive) */\n      this.next_prompt = this.prompt;\n    }\n    print_promptval() {\n      if (!this.with_prompt) return; /* (skip in non-interactive) */\n      this.next_prompt += this.promptval; // (assume that print_sol has been called)\n    }\n    display_status(str) { // toplevel:display_status/1\n      if (!this.with_prompt) return; /* (skip in non-interactive) */\n      if (str === 'silent') return; /* skip this status */\n      this.display('\\n');\n      this.display(str);\n      this.display('\\n');\n    }\n    display_status_new_prompt(str) { /* show status and a new prompt */\n      this.display_status(str);\n      this.print_prompt();\n    }\n    set_log(text) { }\n\n    // TODO: refactor with ciao_playground.js\n    async #treat_enter_(text) {\n      const cproc = this.pg.cproc;\n      if (cproc.is_waiting_for_line()) {\n        if (!cproc.check_not_locked(this)) return; // TODO: not possible?\n        await cproc.send_line(this, text);\n      } else {\n        // Perform query\n        if (text === '') {\n          this.print_prompt(); // show prompt again\n        } else {\n          if (text.slice(-1) !== '.') { // query is malformed\n            // TODO: accept multiline inputs?\n            this.display(`\\\n{SYNTAX ERROR: Malformed query. It must end with a period.}\n`);\n            this.display_status_new_prompt('silent');\n          } else {\n            let q = text.slice(0, -1);\n            await cproc.run_query(this, q, {});\n          }\n        }\n      }\n    }\n\n    /* Interaction loop */\n    async loop() {\n      const cproc = this.pg.cproc;\n      let q_prompt = this.prompt;\n      while (true) {\n        let text;\n        try {\n          text = await this.rl.question(q_prompt);\n        } catch (err) {\n          console.log('Err: ' + Err);\n          process.exit(1);\n        }\n        // TODO: do not capture 'halt.' here, set status from Prolog (so that exit code is properly notified)\n        if (text.slice(-1) === '.' && text.slice(0, -1) === \"halt\") {\n          break;\n        }\n        await this.#treat_enter_(text);\n        q_prompt = this.next_prompt;\n        this.next_prompt = \"\";\n      }\n    }\n  }\n\n  toplevelCfg.statistics = false;\n  use_webworker = false;\n\n  (async () => {\n    // Start a new toplevel and connect to a RLPGCell for interaction\n    const cproc = new ToplevelProc(site_path + '/ciao/');\n    var pg = new RLPGCell(cproc);\n    await pg.setup(rl);\n\n    // Mount current directory as /local\n    // TODO: customize\n    var currdir = process.cwd();\n    var dstdir = '/local';\n    cproc.w.llciao.mount_dir(currdir, dstdir);\n    // Change directory\n    // FS.chdir(dstdir); // TODO: FS.chdir does not seem to work, change from Prolog\n    await cproc.muted_query_dumpout(`working_directory(_,'${dstdir}')`);\n  });\n}\n\nexports.CiaoWorker = CiaoWorker;\n","import { CiaoWorker } from \"../core/js/ciao-prolog\";\n\nexport type cp_query = {\n    name: string,\n    args: cp_term[]\n}\n\nexport type QueryResponse = {\n    cont: string;\n    arg: string;\n}\n\n// Term - Atm, Num, String, Struct\nexport type cp_term =\n    | cp_atm\n    | cp_num\n    | cp_string\n    | cp_struct;\n\n// Integer\nexport type cp_int = {\n    tag: 'int';\n    value: number;\n};\n\n// Float\nexport type cp_flt = {\n    tag: 'flt';\n    value: number;\n};\n\n// Number\nexport type cp_num = cp_int | cp_flt;\n\n// Struct\nexport type cp_struct = {\n    tag: 'struct';\n    value: object;\n};\n\n// Atom\nexport type cp_atm = {\n    tag: 'atm';\n    value: string;\n};\n\n// String\nexport type cp_string = {\n    tag: 'string';\n    value: string;\n};\n\nexport type CiaoConfig = {\n    boot_path: string;\n    curr_dir: string;\n    init_bundles: string[];\n    cust_modules: string[];\n    cust_modules_path: string;\n    init_queries: string[];\n}\n\nexport class CiaoPrologInterface {\n    private c_config: CiaoConfig;\n    private c_worker: CiaoWorker;\n\n    constructor(curr_dir: string, bundles: string[], cust_modules: string[] = [], cust_modules_path?: string, boot_path?: string) {\n        this.c_config = {\n            boot_path: boot_path ?? './nod