Create tutorial_37.py

simply-coded · web-flow · commit 6daad4195ff1 · 2017-06-29T14:41:15.000-05:00
diff --git a/code/tutorial_37.py b/code/tutorial_37.py
@@ -0,0 +1,103 @@
+###
+# video challenge answer
+#
+def get_money(customer, amount):              
+    # calculate money needed to cover the "amount" to the nearest 5 dollar bill
+    nonfive_bills = amount % 5
+    remfive_bills = amount - nonfive_bills    
+    needed = remfive_bills + (0 if nonfive_bills == 0 else 5)
+    # take that money out of the customers wallet
+    customer['wallet'] -= needed    
+    # return the money you calculated to pay for the meal
+    return needed
+
+###
+# factory functions
+#
+def make_is_divisble(den):
+
+    def is_divisible(num):
+        return num % den == 0
+
+    return is_divisible
+
+# create functions
+is_div_2 = make_is_divisble(2)
+is_div_13 = make_is_divisble(13)
+
+# use them
+a = is_div_2(12)
+b = is_div_2(345+16122-48//45)
+c = is_div_2(23*41981)
+
+d = is_div_13(341)
+e = is_div_13(5+12-48)
+f = is_div_13(54*81)
+
+# use it without saving the function
+g = make_is_divisble(5)(1615)
+
+
+###
+# wrap existing functions
+#
+def whats_running(function):
+    """Says when a function starts and stops.
+
+    @usage
+    your_function = whats_running(your_function)
+    """
+
+    def new_function():
+        print(function.__name__, 'has started.')
+        function()
+        print(function.__name__, 'has stopped.')
+
+    return new_function
+
+
+def time_this(function):
+    """Times a function in seconds.
+
+    @usage
+    your_function = time_this(your_function)
+    """
+    import time
+
+    def wrapper(*args, **kargs):
+        start = time.time()
+        result = function(*args, **kargs)
+        stop = time.time()
+        print(f'{function.__name__} took {stop - start} seconds to execute.')
+        return result
+
+    wrapper.__name__ = function.__name__ + '_timed'
+    return wrapper
+
+# used for example functions
+club = ['jake', 'alice', 'mark', 'john', 'jerry', 'kipper']
+
+# example functions
+def counter():
+    for x in range(1_000_000):
+        pass
+
+def in_club(name, my_club=club):
+    return name in my_club
+
+# apply the wrapper functions
+counter = time_this(counter)
+in_club = time_this(in_club)
+
+# you can apply a wrapper to an existing wrapped function
+counter = whats_running(counter)
+
+# call our newly wrapped functions
+counter()
+
+if in_club('jake'):
+    print('They are in the club.')
+else:
+    print('They are not in the club.')
+
+counter()
