Viewing file: counter.py (1.26 KB) -rw-r--r-- Select action/file-type: (+) | (+) | (+) | Code (+) | Session (+) | (+) | SDB (+) | (+) | (+) | (+) | (+) | (+) |
# -*- Mode: Python; tab-width: 4 -*-
# It is tempting to add an __int__ method to this class, but it's not # a good idea. This class tries to gracefully handle integer # overflow, and to hide this detail from both the programmer and the # user. Note that the __str__ method can be relied on for printing out # the value of a counter: # # >>> print 'Total Client: %s' % self.total_clients # # If you need to do arithmetic with the value, then use the 'as_long' # method, the use of long arithmetic is a reminder that the counter # will overflow.
class counter: "general-purpose counter"
def __init__ (self, initial_value=0): self.value = initial_value def increment (self, delta=1): result = self.value try: self.value = self.value + delta except OverflowError: self.value = long(self.value) + delta return result
def decrement (self, delta=1): result = self.value try: self.value = self.value - delta except OverflowError: self.value = long(self.value) - delta return result
def as_long (self): return long(self.value)
def __nonzero__ (self): return self.value != 0
def __repr__ (self): return '<counter value=%s at %x>' % (self.value, id(self))
def __str__ (self): return str(long(self.value)) #return str(long(self.value))[:-1]
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