message: Tiny code simplification.
diff: @@ -131,14 +131,13 @@ impl MmapCache {
  }
  self.cache.remove(full_path);
  self.counters.miss += 1;
  - Ok(if let Some(mmap) = open_mmap(full_path)? {
  + let mmap_opt = open_mmap(full_path)?;
  + Ok(mmap_opt.map(|mmap| {
  let mmap_arc: Arc<BoxedData> = Arc::new(Box::new(mmap));
  let mmap_weak = Arc::downgrade(&mmap_arc);
  self.cache.insert(full_path.to_owned(), mmap_weak);
  - Some(mmap_arc)
  - } else {
  - None
  - })
  + mmap_arc
  + }))
  }
  }
  