More cleanup.

[python_utils.git] / stopwatch.py

diff --git a/stopwatch.py b/stopwatch.py
index c6c154c124482c9bf9c9e20950a9cca0fb22cb1d..ae8e01aa18452ed932ef589b9047c7f0c68ab58a 100644 (file)
--- a/stopwatch.py
+++ b/stopwatch.py
@@ -1,10 +1,13 @@
 #!/usr/bin/env python3
 
+"""A simple stopwatch decorator / context for timing things."""
+
+import contextlib
 import time
-from typing import Callable, Optional
+from typing import Callable, Literal
 
 
-class Timer(object):
+class Timer(contextlib.AbstractContextManager):
     """
     A stopwatch to time how long something takes (walltime).
 
@@ -29,6 +32,6 @@ class Timer(object):
         self.end = 0.0
         return lambda: self.end - self.start
 
-    def __exit__(self, *args) -> Optional[bool]:
+    def __exit__(self, *args) -> Literal[False]:
         self.end = time.perf_counter()
-        return None  # don't suppress exceptions
+        return False