Method expect

packages/core/src/constraints/parser.ts:385–389

(token: string)

  }

  private expect(token: string): void {
    if (!this.consumeIf(token)) {
      this.fail(`Expected "${token}"`);
    }
  }

  private consumeIf(token: string): boolean {
    if (this.source.startsWith(token, this.pos)) {