if (entry.getUpperBound().compareTo(subRange.lowerBound) <= 0) {
                  return endOfData();
                }
                return immutableEntry(entry.getKey().intersection(subRange), entry.getValue());
              }
              return endOfData();
            }
          };
        }
      };
    }

    @Override

                if (entry.getUpperBound().compareTo(subRange.lowerBound) <= 0) {
                  return endOfData();
                }
                return immutableEntry(entry.getKey().intersection(subRange), entry.getValue());
              }
              return endOfData();
            }
          };
        }
      };
    }

    @Override

          while (!elemItr.hasNext()) {
            if (rangeItr.hasNext()) {
              elemItr = ContiguousSet.create(rangeItr.next(), domain).iterator();
            } else {
              return endOfData();
            }
          }
          return elemItr.next();
        }
      };
    }

    @Override
    @GwtIncompatible("NavigableSet")

          T child = top.childIterator.next();
          stack.addLast(expand(child));
        } else {
          stack.removeLast();
          return top.root;
        }
      }
      return endOfData();
    }

    private PostOrderNode<T> expand(T t) {
      return new PostOrderNode<>(t, children(t).iterator());
    }
  }

  /**

                if (!collection.isEmpty()) {
                  return immutableEntry(key, collection);
                }
              }
              return endOfData();
            }
          };
        }

        @Override
        public boolean removeAll(Collection<?> c) {
          return removeEntriesIf(in(c));
        }

        @Override

                if (!collection.isEmpty()) {
                  return immutableEntry(key, collection);
                }
              }
              return endOfData();
            }
          };
        }

        @Override
        public boolean removeAll(Collection<?> c) {
          return removeEntriesIf(in(c));
        }

        @Override

          if (!duplicate) {
            lastValue = next;
            return lastValue;
          }
        }

        lastValue = null; // clear reference to unused data
        return endOfData();
      }
    };
  }

  private static final long serialVersionUID = 0;

              Optional<? extends T> optional = iterator.next();
              if (optional.isPresent()) {
                return optional.get();
              }
            }
            return endOfData();
          }
        };
      }
    };
  }

  private static final long serialVersionUID = 0;

          @Override
          @CheckForNull
          protected Entry<E> computeNext() {
            while (true) {
              if (!mapEntries.hasNext()) {
                return endOfData();
              }
              Map.Entry<E, AtomicInteger> mapEntry = mapEntries.next();
              int count = mapEntry.getValue().get();
              if (count != 0) {

            String next = lines.next();
            // skip last line if it's empty
            if (lines.hasNext() || !next.isEmpty()) {
              return next;
            }
          }
          return endOfData();
        }
      };
    }

    @Override
    public Stream<String> lines() {
      return stream(linesIterator());
    }

    @Override
    @CheckForNull