B
Bronner, Gregory
I'm trying to create a type-safe subclass of int (SpecialInt) such that
instances of the class can only be compared with ints, longs, and other
subclasses of SpecialInt -- I do not want them to be compared with
floats, bools, or strings, which the native int implementation supports.
Obviously, I could overload __lt_, __eq__, __le__, etc, and write a
bunch of boilerplate code.
Should this code throw an exception if the types are not comparable?
What would I lose by doing that?
Is this code likely to be efficient?
def __gt__(self, other):
if(other is self):
return False
if(self.__isComparable(other)):
return int(self)>int(other)
else:
raise ValueError(str(self) +" and "+ str(other)
+" are not comparable")
The native implementation of int goes to great lengths to allow
illogical comparisons such as the one below.False
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instances of the class can only be compared with ints, longs, and other
subclasses of SpecialInt -- I do not want them to be compared with
floats, bools, or strings, which the native int implementation supports.
Obviously, I could overload __lt_, __eq__, __le__, etc, and write a
bunch of boilerplate code.
Should this code throw an exception if the types are not comparable?
What would I lose by doing that?
Is this code likely to be efficient?
def __gt__(self, other):
if(other is self):
return False
if(self.__isComparable(other)):
return int(self)>int(other)
else:
raise ValueError(str(self) +" and "+ str(other)
+" are not comparable")
The native implementation of int goes to great lengths to allow
illogical comparisons such as the one below.False
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
This message is intended only for the personal and confidential use of the designated recipient(s) named above. If you are not the intended recipient of this message you are hereby notified that any review, dissemination, distribution or copying of this message is strictly prohibited. This communication is for information purposes only and should not be regarded as an offer to sell or as a solicitation of an offer to buy any financial product, an official confirmation of any transaction, or as an official statement of Lehman Brothers. Email transmission cannot be guaranteed to be secure or error-free. Therefore, we do not represent that this information is complete or accurate and it should not be relied upon as such. All information is subject to change without notice.