bolt/src/util.ts

export interface FastStringMap<T> {
  [key: string]: T
}

export interface Stream<T> {
  get(): T;
  peek(count?: number): T;
}

export class StreamWrapper<T> {

  offset = 0

  constructor(protected data: T[], protected createSentry: () => T) {

  }

  peek(count = 1) {
    const offset = this.offset + (count - 1);
    if (offset >= this.data.length) {
      return this.createSentry();
    }
    return this.data[offset];
  }

  get() {
    if (this.offset >= this.data.length) {
      return this.createSentry();
    }
    return this.data[this.offset++];
  }

}