import time

def timer(label='', trace=True):                # On decorator args: retain args
    def onDecorator(func):                      # On @: retain decorated func
        def onCall(*args, **kargs):             # On calls: call original
            start   = time.clock()              # State is scopes + func attr
            result  = func(*args, **kargs)
            elapsed = time.clock() - start
            onCall.alltime += elapsed
            if trace:
                format = '%s%s: %.5f, %.5f'
                values = (label, func.__name__, elapsed, onCall.alltime)
                print(format % values)
            return result
        onCall.alltime = 0
        return onCall
    return onDecorator



# Test on functions

@timer(trace=True, label='[CCC]==>')
def listcomp(N):                        # Like listcomp = timer(...)(listcomp)
    return [x * 2 for x in range(N)]    # listcomp(...) triggers onCall     

@timer(trace=True, label='[MMM]==>')
def mapcall(N):
    return list(map((lambda x: x * 2), range(N)))        # list for 3.0 views

for func in (listcomp, mapcall):
    result = func(5)            # Time for this call, all calls, return value
    func(5000000)
    print(result)  
    print('allTime = %s\n' % func.alltime)   # Total time for all calls



# Test on methods

class Person:
    def __init__(self, name, pay):
        self.name = name
        self.pay  = pay

    @timer()
    def giveRaise(self, percent):           # giveRaise = timer()(giverRaise)
        self.pay *= (1.0 + percent)         # tracer remembers giveRaise

    @timer(label='**')
    def lastName(self):                     # lastName = timer(...)(lastName)
        return self.name.split()[-1]        # alltime per class, not instance

bob = Person('Bob Smith', 50000)
sue = Person('Sue Jones', 100000)
bob.giveRaise(.10)
sue.giveRaise(.20)                          # runs onCall(sue, .10)
print(bob.pay, sue.pay)
print(bob.lastName(), sue.lastName())       # runs onCall(bob), remembers lastName
print('%.5f %.5f' % (Person.giveRaise.alltime, Person.lastName.alltime))



# Expected output

[CCC]==>listcomp: 0.00002, 0.00002
[CCC]==>listcomp: 1.19636, 1.19638
[0, 2, 4, 6, 8]
allTime = 1.19637775192

[MMM]==>mapcall: 0.00002, 0.00002
[MMM]==>mapcall: 2.29260, 2.29262
[0, 2, 4, 6, 8]
allTime = 2.2926232943

giveRaise: 0.00001, 0.00001
giveRaise: 0.00001, 0.00002
55000.0 120000.0
**lastName: 0.00001, 0.00001
**lastName: 0.00001, 0.00002
Smith Jones
0.00002 0.00002