update from Atlas

attributes/exists_truthy.py

@@ -0,0 +1,43 @@
+import timeit
+
+def exists_and_truthy_hasattr(obj, attr_name):
+    if hasattr(obj, attr_name):
+        return bool(getattr(obj, attr_name))
+    else:
+        return False
+
+def exists_and_truthy_getattr(obj, attr_name):
+    return bool(getattr(obj, attr_name, False))
+
+def exists_and_truthy_tryget(obj, attr_name):
+    try:
+        return bool(getattr(obj, attr_name))
+    except AttributeError:
+        return False
+
+
+class Gizmo:
+    def __init__(self):
+        self.gadget = True
+
+gizmo = Gizmo()
+
+test_keys = 'hasattr', 'getattr', 'tryget'
+
+def average(timings):
+    sample = timings[1:-1]
+    return sum(sample) / len(sample)
+
+def do_tests():
+    for test_key in test_keys:
+        func_name = 'exists_and_truthy_' + test_key
+        test = func_name + '(gizmo, "gadget")'
+        setup = 'from __main__ import gizmo, ' + func_name
+        elapsed = average(timeit.repeat(test, repeat=5, setup=setup))
+        print(test_key.rjust(7), format(elapsed, '0.5f'))
+
+if __name__ == '__main__':
+    do_tests()
+    del gizmo.gadget
+    do_tests()
+

attributes/hasattr.py

@@ -0,0 +1,44 @@
+import timeit
+
+test_hasattr = """
+if hasattr(gizmo, 'gadget'):
+    feature = gizmo.gadget
+else:
+    feature = None
+"""
+
+test_getattr = """
+feature = getattr(gizmo, 'gadget', None)
+"""
+
+test_tryget = """
+try:
+    feature = getattr(gizmo, 'gadget')
+except AttributeError:
+    feature = None
+"""
+
+
+class Gizmo:
+    def __init__(self):
+        self.gadget = True
+
+gizmo = Gizmo()
+
+test_keys = 'hasattr', 'getattr', 'tryget'
+
+
+def test():
+    for test_key in test_keys:
+        test_name = 'test_' + test_key
+        test = globals()[test_name]
+        setup = 'from __main__ import gizmo'
+        t_present = min(timeit.repeat(test, setup=setup))
+        del gizmo.gadget
+        t_absent = min(timeit.repeat(test, setup=setup))
+        gizmo.gadget = True
+        print('{:7}  {:.3f}  {:.3f}'.format(test_key, t_present, t_absent))
+
+if __name__ == '__main__':
+    test()
+