-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 06/10/2010 03:49 PM, DE wrote:
[...] If you're doing anything more than simple addition and subtraction, it probably will be.
forgive me for repeating myself but yes, you did everything right i recalled that one ought to first measure and only then optimize (first shoot then ask questions...)
:-)
The library's fixed-size integers act like unsigned ints, as far as modular arithmetic goes. Except, of course, that they're signed as well. That's why I took pains to describe their behavior thoroughly, it's not entirely obvious from knowledge of the built-in types.
it's rather unusual for me so if i want to go unsigned bigint i just ignore the sign of fixed integers (in other words they're all positive) am i right?
In most cases, that will work, because overflows will be truncated to the proper number of bits. I hadn't considered underflows though, until you mentioned it in your next paragraph.
one small issue i can think about is 'a - b' where a<b according to mod. arith. 'a - b' is equivalent to '(mod + a - b)%mod' is that case preserved by fixed_integer?
Not at present. It would be easy enough to add that to the current design though, as yet another template parameter (Signed/Unsigned). I've put that on the to-do list. I'm not sure whether that will make the fifth release (which I hope to have ready tomorrow, if all goes well, so people can play with it over the weekend). If it doesn't, I'll add it as soon after that as I can.
i misunderstood the docs and probably poorly expressed my thought sorry
I'm not sure you did. I hadn't considered how negative numbers would affect that. If that's the cause of the misunderstanding, it was entirely my fault, and I apologize. - -- Chad Nelson Oak Circle Software, Inc. * * * -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAkwRXbMACgkQp9x9jeZ9/wQj3ACg7xNVheu1v1Y30KtAZA4UWul7 W+kAn1gXiUfkjSJDPEQvbsunXx1gVu7+ =5dYy -----END PGP SIGNATURE-----