text: //
  //  RACDynamicSequence.h
  //  ReactiveCocoa
  //
  //  Created by Justin Spahr-Summers on 2012-10-29.
  //  Copyright (c) 2012 GitHub. All rights reserved.
  //
  
  #import "RACSequence.h"
  
  // Private class that implements a sequence dynamically using blocks.
  @interface RACDynamicSequence : RACSequence
  
  // Returns a sequence which evaluates `dependencyBlock` only once, the first
  // time either `headBlock` or `tailBlock` is evaluated. The result of
  // `dependencyBlock` will be passed into `headBlock` and `tailBlock` when
  // invoked.
  + (RACSequence *)sequenceWithLazyDependency:(id (^)(void))dependencyBlock headBlock:(id (^)(id dependency))headBlock tailBlock:(RACSequence *(^)(id dependency))tailBlock;
  
  @end
  