text: //
  //  FCBasics.m
  //  Overcast
  //
  //  Created by Marco Arment on 6/10/16.
  //  Copyright © 2016 Marco Arment. All rights reserved.
  //
  
  #import <Foundation/Foundation.h>
  #import "FCBasics.h"
  
  void fc_executeOnMainThread(void (^block)(void))
  {
      static dispatch_once_t onceToken;
      dispatch_once(&onceToken, ^{
          dispatch_queue_set_specific(dispatch_get_main_queue(), &onceToken, &onceToken, NULL);
      });
  
      if (dispatch_get_specific(&onceToken) == &onceToken) {
          block();
      } else {
          dispatch_async(dispatch_get_main_queue(), block);
      }
  }
  
  