antlr4ng/dist/atn/helpers.mjs

Alternative JavaScript/TypeScript runtime for ANTLR4

var __defProp = Object.defineProperty;
var __name = (target, value) => __defProp(target, "name", { value, configurable: true });

// src/utils/MurmurHash.ts
var c1 = 3432918353;
var c2 = 461845907;
var r1 = 15;
var r2 = 13;
var m = 5;
var n = 3864292196;
var MurmurHash = class _MurmurHash {
  static {
    __name(this, "MurmurHash");
  }
  static defaultSeed = 701;
  constructor() {
  }
  /**
   * Initialize the hash using the specified {@code seed}.
   *
   * @param seed the seed
   *
   * @returns the intermediate hash value
   */
  static initialize(seed = _MurmurHash.defaultSeed) {
    return seed;
  }
  static updateFromComparable(hash, value) {
    return this.update(hash, value?.hashCode() ?? 0);
  }
  /**
   * Update the intermediate hash value for the next input {@code value}.
   *
   * @param hash The intermediate hash value.
   * @param value the value to add to the current hash.
   *
   * @returns the updated intermediate hash value
   */
  static update(hash, value) {
    value = Math.imul(value, c1);
    value = value << r1 | value >>> 32 - r1;
    value = Math.imul(value, c2);
    hash = hash ^ value;
    hash = hash << r2 | hash >>> 32 - r2;
    hash = Math.imul(hash, m) + n;
    return hash;
  }
  /**
   * Apply the final computation steps to the intermediate value {@code hash}
   * to form the final result of the MurmurHash 3 hash function.
   *
   * @param hash The intermediate hash value.
   * @param entryCount The number of values added to the hash.
   *
   * @returns the final hash result
   */
  static finish(hash, entryCount) {
    hash ^= entryCount * 4;
    hash ^= hash >>> 16;
    hash = Math.imul(hash, 2246822507);
    hash ^= hash >>> 13;
    hash = Math.imul(hash, 3266489909);
    hash ^= hash >>> 16;
    return hash;
  }
  /**
   * An all-in-one convenience method to compute a hash for a single value.
   *
   * @param value The value to hash.
   * @param seed The seed for the hash value.
   *
   * @returns The computed hash.
   */
  static hashCode(value, seed) {
    return _MurmurHash.finish(_MurmurHash.update(seed ?? _MurmurHash.defaultSeed, value), 1);
  }
};

// src/atn/PredictionContext.ts
var PredictionContext = class _PredictionContext {
  static {
    __name(this, "PredictionContext");
  }
  /**
   * Represents `$` in an array in full context mode, when `$`
   * doesn't mean wildcard: `$ + x = [$,x]`. Here,
   * `$` = {@link EMPTY_RETURN_STATE}.
   */
  static EMPTY_RETURN_STATE = 2147483647;
  static traceATNSimulator = false;
  cachedHashCode;
  constructor(cachedHashCode) {
    this.cachedHashCode = cachedHashCode;
  }
  static calculateEmptyHashCode() {
    let hash = MurmurHash.initialize(31);
    hash = MurmurHash.finish(hash, 0);
    return hash;
  }
  static calculateHashCodeSingle(parent, returnState) {
    let hash = MurmurHash.initialize(31);
    hash = MurmurHash.updateFromComparable(hash, parent);
    hash = MurmurHash.update(hash, returnState);
    hash = MurmurHash.finish(hash, 2);
    return hash;
  }
  static calculateHashCodeList(parents, returnStates) {
    let hash = MurmurHash.initialize(31);
    for (const parent of parents) {
      hash = MurmurHash.updateFromComparable(hash, parent);
    }
    for (const returnState of returnStates) {
      hash = MurmurHash.update(hash, returnState);
    }
    hash = MurmurHash.finish(hash, 2 * parents.length);
    return hash;
  }
  isEmpty() {
    return false;
  }
  hasEmptyPath() {
    return this.getReturnState(this.length - 1) === _PredictionContext.EMPTY_RETURN_STATE;
  }
  hashCode() {
    return this.cachedHashCode;
  }
  toString(_recog) {
    return "";
  }
};

// src/atn/SingletonPredictionContext.ts
var SingletonPredictionContext = class _SingletonPredictionContext extends PredictionContext {
  static {
    __name(this, "SingletonPredictionContext");
  }
  parent;
  returnState;
  constructor(parent, returnState) {
    super(
      parent ? PredictionContext.calculateHashCodeSingle(parent, returnState) : PredictionContext.calculateEmptyHashCode()
    );
    this.parent = parent ?? null;
    this.returnState = returnState;
  }
  getParent(_index) {
    return this.parent;
  }
  getReturnState(_index) {
    return this.returnState;
  }
  equals(other) {
    if (this === other) {
      return true;
    }
    if (!(other instanceof _SingletonPredictionContext)) {
      return false;
    }
    if (this.hashCode() !== other.hashCode()) {
      return false;
    }
    if (this.returnState !== other.returnState) {
      return false;
    }
    if (this.parent == null) {
      return other.parent == null;
    }
    return this.parent.equals(other.parent);
  }
  toString() {
    const up = this.parent === null ? "" : this.parent.toString();
    if (up.length === 0) {
      if (this.returnState === PredictionContext.EMPTY_RETURN_STATE) {
        return "$";
      }
      return "" + this.returnState;
    } else {
      return "" + this.returnState + " " + up;
    }
  }
  get length() {
    return 1;
  }
};

// src/atn/EmptyPredictionContext.ts
var EmptyPredictionContext = class _EmptyPredictionContext extends SingletonPredictionContext {
  static {
    __name(this, "EmptyPredictionContext");
  }
  /**
   * Represents `$` in local context prediction, which means wildcard.
   * `*+x = *`.
   */
  static instance = new _EmptyPredictionContext();
  constructor() {
    super(void 0, PredictionContext.EMPTY_RETURN_STATE);
  }
  isEmpty() {
    return true;
  }
  getParent() {
    return null;
  }
  getReturnState() {
    return this.returnState;
  }
  equals(other) {
    return this === other;
  }
  toString() {
    return "$";
  }
};

// src/atn/helpers.ts
var createSingletonPredictionContext = /* @__PURE__ */ __name((parent, returnState) => {
  if (returnState === PredictionContext.EMPTY_RETURN_STATE && parent === null) {
    return EmptyPredictionContext.instance;
  } else {
    return new SingletonPredictionContext(parent, returnState);
  }
}, "createSingletonPredictionContext");
export {
  createSingletonPredictionContext
};