X-Git-Url: https://wannabe.guru.org/gitweb/?a=blobdiff_plain;f=stopwatch.py;h=cdd405b558213a9fb7c0ca38eec72ad41ba47a14;hb=822454f580c1ff9eb207b8da46cdfae24e30cde1;hp=d54af8792d28eef4025c150cb1920fbd2113efee;hpb=1574e8a3a8982fab9278ad534f9427d464e4bffb;p=python_utils.git

diff --git a/stopwatch.py b/stopwatch.py
index d54af87..cdd405b 100644
--- a/stopwatch.py
+++ b/stopwatch.py
@@ -6,11 +6,15 @@ from typing import Callable
 
 class Timer(object):
     """
-    with timer.Timer() as t:
-        do_the_thing()
+    A stopwatch to time how long something takes (walltime).
 
-    walltime = t()
-    print(f'That took {walltime}s.')
+    e.g.
+
+        with timer.Timer() as t:
+            do_the_thing()
+
+        walltime = t()
+        print(f'That took {walltime} seconds.')
     """
 
     def __init__(self) -> None:
@@ -18,10 +22,13 @@ class Timer(object):
         self.end = None
 
     def __enter__(self) -> Callable[[], float]:
+        """Returns a functor that, when called, returns the walltime of the
+        operation in seconds.
+        """
         self.start = time.perf_counter()
         self.end = 0.0
         return lambda: self.end - self.start
 
     def __exit__(self, *args) -> bool:
         self.end = time.perf_counter()
-        return True
+        return None  # don't suppress exceptions