Merge pull request #85 from lamweilun/dev/weilun/update_stack_and_queue

Add length, clear and is_empty methods to Stack and Queue

1 files changed, 12 insertions, 0 deletions

diff --git a/std/stack.zc b/std/stack.zc
index 3d7c3c5..7df77f1 100644
--- a/std/stack.zc
+++ b/std/stack.zc
@@ -50,6 +50,18 @@ impl Stack<T> {
     }
     return Option<T>::None();
   }
+
+  fn length(self) -> usize {
+    return self.len;
+  }
+
+  fn clear(self) {
+    self.len = 0;
+  }
+
+  fn is_empty(self) -> bool {
+    return self.len == 0;
+  }
 }
 
 impl Drop for Stack<T> {