Class Int

g2all/700/module/int64.js:41–121

// immutable 64-bit integer
export class Int {
  constructor(low, high) {
    if (high === undefined) {
      this._u32 = new Uint32Array(lohi_from_one(low));
      return;
    }

    if (check_not_in_range(low)) {
      throw TypeError(`low not a 32-bit integer: ${low}`);
    }

    if (check_not_in_range(high)) {
      throw TypeError(`high not a 32-bit integer: ${high}`);
    }

    this._u32 = new Uint32Array([low, high]);
  }

  get lo() {
    return this._u32[0];
  }

  get hi() {
    return this._u32[1];
  }

  // return low/high as signed integers

  get bot() {
    return this._u32[0] | 0;
  }

  get top() {
    return this._u32[1] | 0;
  }

  neg() {
    const u32 = this._u32;
    const low = (~u32[0] >>> 0) + 1;
    return new this.constructor(low >>> 0, ((~u32[1] >>> 0) + (low > 0xffffffff)) >>> 0);
  }

  eq(b) {
    const values = lohi_from_one(b);
    const u32 = this._u32;
    return u32[0] === values[0] && u32[1] === values[1];
  }

  ne(b) {
    return !this.eq(b);
  }

  add(b) {
    const values = lohi_from_one(b);
    const u32 = this._u32;
    const low = u32[0] + values[0];
    return new this.constructor(low >>> 0, (u32[1] + values[1] + (low > 0xffffffff)) >>> 0);
  }