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Remove dependency on boost.format, remove unfettered use of auto in order to move towards C++03 compatibility, use BOOST_THROW_EXCEPTION.

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This commit is contained in:
Nick Thompson
2018-10-24 14:29:22 -06:00
parent 9167594533
commit ada03a59d7
4 changed files with 46 additions and 32 deletions
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9
include/boost/integer/mod_inverse.hpp
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@ -6,7 +6,8 @@
*/
#ifndef BOOST_INTEGER_MOD_INVERSE_HPP
#define BOOST_INTEGER_MOD_INVERSE_HPP
#include <limits>
#include <stdexcept>
#include <boost/throw_exception.hpp>
#include <boost/optional.hpp>
#include <boost/integer/extended_euclidean.hpp>
@ -18,15 +19,13 @@ namespace boost { namespace integer {
// mpz_invert (gmplib)
// modinv (some dude on stackoverflow)
// Would mod_inverse be sometimes mistaken as the modular *additive* inverse?
// In any case, I think this is the best name we can get for this function without agonizing.
template<class Z>
boost::optional<Z> mod_inverse(Z a, Z modulus)
{
using std::numeric_limits;
static_assert(numeric_limits<Z>::is_integer,
"The modular multiplicative inverse works on integral types.\n");
if (modulus < 2)
{
throw std::domain_error("Modulus must be > 1.\n");
BOOST_THROW_EXCEPTION(std::domain_error("Modulus must be > 1.\n"));
}
// make sure a < modulus:
a = a % modulus;