Did something.

src/lib.rs

@@ -51,7 +51,7 @@ where
     pub fn with_capacity(capacity: usize) -> BitSet<B> {
         BitSet {
             blocks: HashMap::with_capacity_and_hasher(
-                capacity / B::bits() as usize,
+                capacity / B::BITS as usize,
                 Default::default(),
             ),
             nbits: 0,
@@ -60,11 +60,11 @@ where
 
     #[inline]
     pub fn capacity(&self) -> usize {
-        self.blocks.capacity() * B::bits() as usize
+        self.blocks.capacity() * B::BITS as usize
     }
 
     pub fn reserve(&mut self, additional: usize) {
-        self.blocks.reserve(additional / B::bits() as usize)
+        self.blocks.reserve(additional / B::BITS as usize)
     }
 
     pub fn shrink_to_fit(&mut self) {