commit 574ccc87bfb857f1325021b697d169f7084aa0cf
Author: luaneko <lumi@lua.re>
Date:   Tue Jan 7 02:58:12 2025 +1100

    Initial commit

diff --git a/async.ts b/async.ts
new file mode 100644
index 0000000..ac222b9
--- /dev/null
+++ b/async.ts
@@ -0,0 +1,204 @@
+function noop() {}
+
+export interface Deferred<T = void> extends Promise<T> {
+  resolve(value: T | PromiseLike<T>): void;
+  reject(reason?: unknown): void;
+}
+
+export function deferred<T = void>() {
+  const { promise, resolve, reject } = Promise.withResolvers<T>();
+  const p = promise as Deferred<T>;
+  return (p.resolve = resolve), (p.reject = reject), p;
+}
+
+export function notifier<T = void>() {
+  let p: Deferred<T> | null = null;
+
+  return {
+    listen(): Promise<T> {
+      return (p ??= deferred());
+    },
+
+    notify(value: T) {
+      p &&= (p.resolve(value), null);
+    },
+  };
+}
+
+export interface Channel<T> {
+  send: Sender<T>;
+  recv: Receiver<T>;
+}
+
+export interface Sender<T> {
+  (value: T): void;
+  close(reason?: unknown): void;
+}
+
+export interface Receiver<T> {
+  (): Promise<T | null> | T | null;
+  try(): T | null;
+  close(reason?: unknown): void;
+}
+
+export function channel<T = void>(): Channel<T> {
+  const q = new Map<number, Entry>();
+  let head = 0;
+  let tail = 0;
+  let open = true;
+  let err: unknown = null;
+
+  type Entry =
+    | { has: true; value: T }
+    | { has: false; value: Deferred<T | null> };
+
+  function send(value: T) {
+    if (open) {
+      const i = head++;
+      let n = q.get(i);
+      if (!n) q.set(i, (n = { has: true, value }));
+      else if (!n.has) q.delete(i), n.value.resolve(value);
+      else n.value = value;
+    } else {
+      if (err !== null) throw err;
+      else return;
+    }
+  }
+
+  function recv() {
+    if (open) {
+      const i = tail++;
+      let n = q.get(i);
+      if (!n) return q.set(i, (n = { has: false, value: deferred() })), n.value;
+      else if (!n.has) return n.value;
+      else return q.delete(i), n.value;
+    } else {
+      if (err !== null) throw err;
+      else return null;
+    }
+  }
+
+  function try_recv() {
+    if (open) {
+      const n = q.get(tail);
+      if (n?.has) return q.delete(tail++), n.value;
+      else return null;
+    } else {
+      return null;
+    }
+  }
+
+  recv.try = try_recv;
+  send.close = recv.close = function close(reason?: unknown) {
+    if (!open) return;
+    else (open = false), (err = reason ?? null);
+    for (const p of q.values()) {
+      if (p.has) continue;
+      else if (err !== null) p.value.reject(err);
+      else p.value.resolve(null);
+    }
+    q.clear();
+  };
+
+  return { send, recv };
+}
+
+channel.sender = function sender<T>(
+  f: (recv: Receiver<T>) => void | PromiseLike<void>
+): Sender<T> {
+  const { send, recv } = channel<T>();
+  Promise.resolve(f(recv)).then(noop).then(recv.close, recv.close);
+  return send;
+};
+
+channel.receiver = function receiver<T>(
+  f: (send: Sender<T>) => void | PromiseLike<void>
+): Receiver<T> {
+  const { send, recv } = channel<T>();
+  Promise.resolve(f(send)).then(noop).then(send.close, send.close);
+  return recv;
+};
+
+export function semaphore(count = 1) {
+  const { send: signal, recv: wait } = channel();
+  let n = count;
+
+  async function acquire() {
+    if (--n < 0) await wait();
+    return release;
+  }
+
+  function release() {
+    if (n++ < 0) signal();
+  }
+
+  function reset(new_count = count) {
+    n = count = new_count;
+  }
+
+  acquire.release = release;
+  acquire.reset = reset;
+  release[Symbol.dispose] = release;
+  release satisfies Disposable;
+
+  return acquire;
+}
+
+export interface PoolToken<T> extends Iterable<T, void, void> {
+  readonly value: T;
+  release(): void;
+}
+
+export function pool<T>(size: number, f: () => T | PromiseLike<T>) {
+  const lock = semaphore(size);
+  const all = new Set<T>();
+  const free: T[] = [];
+  const Token = class implements PoolToken<T> {
+    #value;
+    #open = true;
+
+    get value() {
+      if (this.#open) return this.#value;
+      else throw new TypeError(`borrowed value is already released`);
+    }
+
+    constructor(value: T) {
+      this.#value = value;
+    }
+
+    *[Symbol.iterator]() {
+      yield this.value;
+    }
+
+    release() {
+      this.#open &&=
+        (lock.release(), all.has(this.#value) && free.push(this.#value), false);
+    }
+
+    [Symbol.dispose]() {
+      this.release();
+    }
+  };
+
+  async function acquire(): Promise<PoolToken<T>> {
+    await lock();
+    try {
+      let value;
+      if (free.length !== 0) value = free.pop() as T;
+      else value = await f();
+      return all.add(value), new Token(value);
+    } catch (e) {
+      throw (lock.release(), e);
+    }
+  }
+
+  function forget(value: T) {
+    if (all.delete(value)) {
+      const idx = free.indexOf(value);
+      if (idx !== -1) free.splice(idx, 1);
+    }
+  }
+
+  acquire.forget = forget;
+  return acquire;
+}
diff --git a/bytes.ts b/bytes.ts
new file mode 100644
index 0000000..685c2db
--- /dev/null
+++ b/bytes.ts
@@ -0,0 +1,60 @@
+import {
+  decodeBase64,
+  decodeHex,
+  encodeBase64,
+  encodeHex,
+} from "@std/encoding";
+
+const encoder = new TextEncoder();
+const decoder = new TextDecoder();
+
+export type BinaryLike = string | Uint8Array;
+
+export function from_utf8(s: BinaryLike): string {
+  return typeof s === "string" ? s : decoder.decode(s);
+}
+
+export function to_utf8(s: BinaryLike): Uint8Array {
+  return typeof s === "string" ? encoder.encode(s) : s;
+}
+
+export function encode_utf8(s: BinaryLike, buf: Uint8Array): number {
+  if (typeof s === "string") return encoder.encodeInto(s, buf).written;
+  else return buf.set(s), s.length;
+}
+
+export function from_hex(s: BinaryLike): Uint8Array {
+  return decodeHex(from_utf8(s));
+}
+
+export function to_hex(b: BinaryLike): string {
+  return encodeHex(to_utf8(b));
+}
+
+export function from_base64(s: BinaryLike): Uint8Array {
+  return decodeBase64(from_utf8(s));
+}
+
+export function to_base64(b: BinaryLike): string {
+  return encodeBase64(to_utf8(b));
+}
+
+export { equals as buf_eq, concat as buf_concat } from "@std/bytes";
+
+export function buf_concat_fast(a: Uint8Array, b: Uint8Array) {
+  const m = a.length;
+  const c = new Uint8Array(m + b.length);
+  return c.set(a, 0), c.set(b, m), c;
+}
+
+export function buf_resize(buf: Uint8Array, n: number) {
+  const res = new Uint8Array(n);
+  return res.set(buf.subarray(0, n)), res;
+}
+
+export function buf_xor(a: Uint8Array, b: Uint8Array) {
+  const n = Math.max(a.length, b.length);
+  const c = new Uint8Array(n);
+  for (let i = 0; i < n; i++) c[i] = a[i] ^ b[i];
+  return c;
+}
diff --git a/deno.json b/deno.json
new file mode 100644
index 0000000..d378fb7
--- /dev/null
+++ b/deno.json
@@ -0,0 +1,9 @@
+{
+  "name": "@luaneko/lstd",
+  "version": "0.1.0",
+  "exports": "./mod.ts",
+  "imports": {
+    "@std/bytes": "jsr:@std/bytes@^1.0.4",
+    "@std/encoding": "jsr:@std/encoding@^1.0.6"
+  }
+}
diff --git a/deno.lock b/deno.lock
new file mode 100644
index 0000000..f156b53
--- /dev/null
+++ b/deno.lock
@@ -0,0 +1,21 @@
+{
+  "version": "4",
+  "specifiers": {
+    "jsr:@std/bytes@^1.0.4": "1.0.4",
+    "jsr:@std/encoding@^1.0.6": "1.0.6"
+  },
+  "jsr": {
+    "@std/bytes@1.0.4": {
+      "integrity": "11a0debe522707c95c7b7ef89b478c13fb1583a7cfb9a85674cd2cc2e3a28abc"
+    },
+    "@std/encoding@1.0.6": {
+      "integrity": "ca87122c196e8831737d9547acf001766618e78cd8c33920776c7f5885546069"
+    }
+  },
+  "workspace": {
+    "dependencies": [
+      "jsr:@std/bytes@^1.0.4",
+      "jsr:@std/encoding@^1.0.6"
+    ]
+  }
+}
diff --git a/events.ts b/events.ts
new file mode 100644
index 0000000..e0413dc
--- /dev/null
+++ b/events.ts
@@ -0,0 +1,132 @@
+// deno-lint-ignore-file no-explicit-any
+import { jit } from "./jit.ts";
+
+export class Emitter<F extends (...args: any) => void> {
+  #ls: { f: F; once: boolean }[] = [];
+  #argc = 0;
+
+  get argc() {
+    return this.#argc;
+  }
+
+  get size() {
+    return this.#ls.length;
+  }
+
+  constructor() {
+    this.emit = this.#emit_fast;
+  }
+
+  on(f: F, once: boolean) {
+    this.#ls.push({ f, once });
+    this.#argc = Math.max(this.#argc, f.length);
+
+    if (once) this.emit = this.#emit_slow;
+    else this.#emit_fast = this.#compile();
+    if (this.emit !== this.#emit_slow) this.emit = this.#emit_fast;
+    return this;
+  }
+
+  off(f: F) {
+    const ls = this.#ls;
+    let once = false;
+
+    for (let i = ls.length; i-- !== 0; ) {
+      if (ls[i].f === f) {
+        (once = ls[i].once), ls.splice(i, 1);
+        break;
+      }
+    }
+
+    this.#argc = ls.length ? Math.max(...ls.map(({ f }) => f.length)) : 0;
+    if (!once) this.#emit_fast = this.#compile();
+    if (this.emit !== this.#emit_slow) this.emit = this.#emit_fast;
+    return this;
+  }
+
+  // deno-lint-ignore no-unused-vars
+  emit(...args: Parameters<F>) {
+    return false;
+  }
+
+  listeners() {
+    return this.#ls.map(({ f }) => f);
+  }
+
+  #emit_fast = this.#compile();
+  #emit_slow(...args: Parameters<F>) {
+    const ls = this.#ls;
+    (this.#ls = ls.filter(({ once }) => !once)), (this.emit = this.#emit_fast);
+
+    for (let i = 0, n = ls.length; i < n; i++)
+      Reflect.apply(ls[i].f, undefined, args);
+
+    return ls.length !== 0;
+  }
+
+  #compile(): typeof this.emit {
+    const ls = this.#ls.filter(({ once }) => !once);
+    const ps = [...Array(this.#argc).keys()].map((i) => jit.raw`a${i}`);
+
+    return jit.compiled`function emit(${jit.fragment(", ", ...ps)}) {
+      ${jit.map(" ", ls, ({ f }) => {
+        return jit`${f}(${jit.fragment(", ", ...ps.slice(0, f.length))});`;
+      })}
+      return ${jit.literal(ls.length !== 0)};
+    }`;
+  }
+}
+
+export type EventMap = Record<string | symbol, (...args: any) => void>;
+
+export class TypedEmitter<T extends EventMap> {
+  readonly #events: { [K in keyof T]?: Emitter<T[K]> } = Object.create(null);
+
+  on<K extends keyof T>(name: K, f: T[K]) {
+    return (this.#events[name] ??= new Emitter()).on(f, false), this;
+  }
+
+  once<K extends keyof T>(name: K, f: T[K]) {
+    return (this.#events[name] ??= new Emitter()).on(f, true), this;
+  }
+
+  off<K extends keyof T>(name: K, f: T[K]) {
+    const events = this.#events;
+    if (events[name]?.off(f).size === 0) delete events[name];
+    return this;
+  }
+
+  emit<K extends keyof T>(name: K, ...args: Parameters<T[K]>) {
+    const event = this.#events[name];
+    if (event) return event.emit.apply(event, args);
+    else return false;
+  }
+
+  listeners<K extends keyof T>(name: K) {
+    return this.#events[name]?.listeners() ?? [];
+  }
+
+  static {
+    this.prototype.emit = function emit(
+      this: TypedEmitter<EventMap>,
+      name: string,
+      a: any,
+      b: any,
+      c: any,
+      d: any,
+      e: any
+    ) {
+      const event = this.#events[name];
+      if (!event) return false;
+
+      const { argc } = event;
+      if (argc < 6) {
+        return event.emit(a, b, c, d, e);
+      } else {
+        const args = Array(argc);
+        for (let i = 0; i < argc; i++) args[i] = arguments[i + 1];
+        return event.emit.apply(undefined, args);
+      }
+    } as any;
+  }
+}
diff --git a/func.ts b/func.ts
new file mode 100644
index 0000000..9dbb747
--- /dev/null
+++ b/func.ts
@@ -0,0 +1,32 @@
+// deno-lint-ignore-file no-explicit-any
+export class Callable {
+  static {
+    Object.setPrototypeOf(this.prototype, Function.prototype);
+  }
+
+  get name() {
+    return this.constructor.name;
+  }
+
+  constructor(f: (...args: any) => any) {
+    let self: any;
+
+    if (typeof f.prototype !== "undefined") {
+      self = function call(...args: unknown[]) {
+        return typeof new.target !== "undefined"
+          ? Reflect.construct(f, args, new.target)
+          : f(...args);
+      };
+
+      self.prototype = f.prototype;
+    } else {
+      self = (...args: unknown[]) => f(...args);
+    }
+
+    f = f.bind(self);
+
+    delete self.name;
+    delete self.length;
+    return Object.setPrototypeOf(self, new.target.prototype);
+  }
+}
diff --git a/jit.ts b/jit.ts
new file mode 100644
index 0000000..394bc27
--- /dev/null
+++ b/jit.ts
@@ -0,0 +1,113 @@
+export const jit_format = Symbol.for(`re.lua.lstd.jit_format`);
+
+export interface JitFragment {
+  [jit_format](c: JitCompiler): void;
+}
+
+export function is_jit(x: unknown): x is JitFragment {
+  return typeof x === "object" && x !== null && jit_format in x;
+}
+
+export class JitCompiler {
+  #body = "";
+  #args = new Map<unknown, string>();
+
+  write(s: string | JitFragment) {
+    if (is_jit(s)) s[jit_format](this);
+    else this.#body += s;
+  }
+
+  enclose(x: unknown) {
+    let name = this.#args.get(x);
+    if (!name) this.#args.set(x, (name = `__x${this.#args.size}`));
+    this.write(name);
+  }
+
+  format(x: unknown) {
+    is_jit(x) ? this.write(x) : this.enclose(x);
+  }
+
+  compile() {
+    return new Function(
+      ...this.#args.values(),
+      `"use strict"; return (${this.#body});`
+    )(...this.#args.keys());
+  }
+}
+
+export function jit(
+  { raw: s }: TemplateStringsArray,
+  ...xs: unknown[]
+): JitFragment {
+  return {
+    [jit_format](c) {
+      for (let i = 0, n = s.length; i < n; i++) {
+        if (i !== 0) c.format(xs[i - 1]);
+        c.write(s[i]);
+      }
+    },
+  };
+}
+
+jit.compiled = compiled;
+jit.raw = raw;
+jit.fragment = fragment;
+jit.literal = literal;
+jit.map = map;
+jit.if = condition;
+
+export function compiled<T = unknown>(
+  s: TemplateStringsArray,
+  ...xs: unknown[]
+): T {
+  const c = new JitCompiler();
+  return c.write(jit(s, ...xs)), c.compile();
+}
+
+export function raw(s: TemplateStringsArray, ...xs: unknown[]): JitFragment;
+export function raw(s: string): JitFragment;
+export function raw(
+  s: TemplateStringsArray | string,
+  ...xs: unknown[]
+): JitFragment {
+  s = typeof s === "string" ? s : String.raw(s, ...xs);
+  return {
+    [jit_format](c) {
+      c.write(s);
+    },
+  };
+}
+
+export function fragment(
+  sep: string | JitFragment,
+  ...xs: unknown[]
+): JitFragment {
+  return {
+    [jit_format](c) {
+      for (let i = 0, n = xs.length; i < n; i++) {
+        if (i !== 0) c.write(sep);
+        c.format(xs[i]);
+      }
+    },
+  };
+}
+
+export function literal(x: unknown) {
+  return raw(typeof x === "undefined" ? "undefined" : JSON.stringify(x));
+}
+
+export function map<T>(
+  sep: string | JitFragment,
+  xs: Iterable<T>,
+  f: (value: T, index: number) => unknown
+): JitFragment {
+  return fragment(sep, ...Iterator.from(xs).map(f));
+}
+
+export function condition(
+  test: unknown,
+  consequent: JitFragment,
+  alternate: JitFragment = jit``
+): JitFragment {
+  return test ? consequent : alternate;
+}
diff --git a/mod.ts b/mod.ts
new file mode 100644
index 0000000..e69de29