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#!/usr/bin/env python3
class Serial:
_modulus = 2 ** 32
_bitmask = _modulus - 1
_signbit = _modulus >> 1
def __init__(self, val):
self._val = int(val) & self._bitmask
def __add__(self, val):
return self.__class__(self._val + int(val))
def __le__(self, other):
return (self._modulus - int(self) + int(other)) & self._signbit == 0
def __ge__(self, other):
return (self._modulus + int(self) - int(other)) & self._signbit == 0
def __eq__(self, other):
return int(self) == int(other)
def __ne__(self, other):
return int(self) != int(other)
def __lt__(self, other):
return self != other and self <= other
def __gt__(self, other):
return self != other and self >= other
def __int__(self):
return self._val
def __str__(self):
return str(int(self))
if __name__ == "__main__":
from random import randint
for test in range(100):
i1 = Serial(randint(0, 2**32-1))
i2 = Serial(randint(0, 2**32-1))
assert i1 == i2 or \
(i1 < i2 and not (i1 > i2)) or \
(i1 > i2 and not (i1 < i2)) or \
int(i1) & int(i2) == 0x80000000
if i1 == i2:
print(f"{int(i1):10d} == {int(i2):10d}, how did that happen?")
elif i1 < i2:
print(f"{int(i1):10d} => {int(i2):10d}, can do it in one jump")
else:
i3 = i1 + (2**31 - 2)
print(f"{int(i1):10d} => {int(i2):10d}, need to wrap, i3 value {i3}")
assert i1 < i3 and i3 < i2
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