int/long unification hides bugs
kartick_vaddadi at yahoo.com
Tue Oct 26 06:05:30 CEST 2004
> The question is how small is small? Less than 2**7? Less than 2**15?
> Less than 2**31? Less than 2**63? And what's the significance of powers
> of two? And what happens if you move from a 32 bit machine to a 64 bit
> one? (or a 1024 bit one in a hundred years time?)
less than 2**31 most of the time & hardly ever greater than 2**63 - no
matter if my machine is 32-bit, 64-bit or 1024-bit. the required range
depends on the data u want 2 store in the variable & not on the
> > PEP 237 says, "It will give new Python programmers [...] one less
> > thing to learn [...]". i feel this is not so important as the quality
> > of code a programmer writes once he does learn the language.
> The thing is, the int/long cutoff is arbitrary, determined soley by
> implemetation detail.
agreed, but it need not be that way. ints can be defined to be 32-bit
(or 64-bit) on all architectures.
> A much better idea is the judicious use of assertions.
> assert x < 15000
> Not only does it protect you from runaway numbers, it also documents
> what the expected range is, resulting in a much better "quality of code"
such an assertion must be placed before avery assignment to the
variable - & that's tedious. moreover, it can give u a false sense of
security when u think u have it wherever needed but u've forgotten it
a 32-bit limit is a crude kind of assertion that u get for free, and
one u expect should hold for most variables. for those few variables
it doesn't, u can use a long.
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