money.py

   1 import decimal
   2
   3 class money(object):
   4     def __init__(self, amount="0"):
   5         try:
   6             if isinstance(amount, money):
   7                 amount = amount.amount
   8             self.amount = decimal.Decimal(amount)
   9         except decimal.InvalidOperation:
  10             raise ValueError("amount value could not be converted to "
  11                              "Decimal(): '{}'".format(amount))
  12
  13     def amount(self):
  14         return self.amount
  15
  16     def __hash__(self):
  17         return hash(self.amount)
  18
  19     def __repr__(self):
  20         return "{}".format(self.amount)
  21
  22     def __str__(self):
  23         return self.__unicode__().encode('utf-8')
  24
  25     def __unicode__(self):
  26         return u"${:,.2f}".format(self.amount)
  27
  28     def __lt__(self, other):
  29         if not isinstance(other, money):
  30             other = money(other)
  31         return self.amount < other.amount
  32
  33     def __le__(self, other):
  34         if not isinstance(other, money):
  35             other = money(other)
  36         return self.amount <= other.amount
  37
  38     def __eq__(self, other):
  39         if isinstance(other, money):
  40             return self.amount == other.amount
  41         return False
  42
  43     def __ne__(self, other):
  44         return not self == other
  45
  46     def __gt__(self, other):
  47         if not isinstance(other, money):
  48             other = money(other)
  49         return self.amount > other.amount
  50
  51     def __ge__(self, other):
  52         if not isinstance(other, money):
  53             other = money(other)
  54         return self.amount >= other.amount
  55
  56     def __add__(self, other):
  57         if not isinstance(other, money):
  58             other = money(other)
  59         other = other.amount
  60         amount = self.amount + other
  61         return self.__class__(amount)
  62
  63     def __radd__(self, other):
  64         return self.__add__(other)
  65
  66     def __sub__(self, other):
  67         if not isinstance(other, money):
  68             other = money(other)
  69         other = other.amount
  70         amount = self.amount - other
  71         return self.__class__(amount)
  72
  73     def __rsub__(self, other):
  74         return (-self).__add__(other)
  75
  76     def __mul__(self, other):
  77         if isinstance(other, money):
  78             other = other.amount()
  79         amount = self.amount * decimal.Decimal(other)
  80         return self.__class__(amount)
  81
  82     def __rmul__(self, other):
  83         return self.__mul__(other)
  84
  85     def __div__(self, other):
  86         return self.__truediv__(other)
  87
  88     def __truediv__(self, other):
  89         if isinstance(other, money):
  90             if other.amount == 0:
  91                 raise ZeroDivisionError()
  92             return self.amount / other.amount
  93         else:
  94             if other == 0:
  95                 raise ZeroDivisionError()
  96             amount = self.amount / decimal.Decimal(other)
  97             return self.__class__(amount)
  98
  99     def __floordiv__(self, other):
 100         if isinstance(other, money):
 101             if other.amount == 0:
 102                 raise ZeroDivisionError()
 103             return self.amount // other.amount
 104         else:
 105             if other == 0:
 106                 raise ZeroDivisionError()
 107             amount = self.amount // other
 108             return self.__class__(amount)
 109
 110     def __mod__(self, other):
 111         if isinstance(other, money):
 112             raise TypeError("modulo is unsupported between two '{}' "
 113                             "objects".format(self.__class__.__name__))
 114         if other == 0:
 115             raise ZeroDivisionError()
 116         amount = self.amount % other
 117         return self.__class__(amount)
 118
 119     def __divmod__(self, other):
 120         if isinstance(other, money):
 121             if other.amount == 0:
 122                 raise ZeroDivisionError()
 123             return divmod(self.amount, other.amount)
 124         else:
 125             if other == 0:
 126                 raise ZeroDivisionError()
 127             whole, remainder = divmod(self.amount, other)
 128             return (self.__class__(whole),
 129                     self.__class__(remainder))
 130
 131     def __pow__(self, other):
 132         if isinstance(other, money):
 133             raise TypeError("power operator is unsupported between two '{}' "
 134                             "objects".format(self.__class__.__name__))
 135         amount = self.amount ** other
 136         return self.__class__(amount)
 137
 138     def __neg__(self):
 139         return self.__class__(-self.amount)
 140
 141     def __pos__(self):
 142         return self.__class__(+self.amount)
 143
 144     def __abs__(self):
 145         return self.__class__(abs(self.amount))
 146
 147     def __int__(self):
 148         return int(self.amount)
 149
 150     def __float__(self):
 151         return float(self.amount)
 152
 153     def __round__(self, ndigits=0):
 154         return self.__class__(round(self.amount, ndigits))