intutils.h File Reference

Miscellaneous utility classes for analysing the built-in integer types at compile time. More...

#include "regina-core.h"
#include "regina-config.h"
#include <cstdint>
#include <limits>
#include <type_traits>

Classes
struct	regina::IsReginaInteger< T >
	Determines if the type T is one of Regina's own integer types (either arbitrary precision or fixed size). More...
struct	regina::IsReginaArbitraryPrecisionInteger< T >
	Determines if the type T is one of Regina's arbitrary precision integer types. More...
struct	regina::IntOfSize< bytes >
	Gives access to native integer types that hold exactly k bytes, where k may be any compile-time constant. More...
struct	regina::IntOfMinSize< bytes >
	Gives access to native integer types that hold at least k bytes, where k may be any compile-time constant. More...

Namespaces
namespace	regina
	Contains the entire Regina calculation engine.

Macros
#define	ENABLE_MEMBER_FOR_REGINA_INTEGER(T, returnType)
	Conditionally enables a member function for a template class only when the type T is one of Regina's own integer classes.
#define	INT128_AVAILABLE
	Defined if and only if native 128-bit arithmetic is available on this platform.

Typedefs
template<int bits>
using	regina::IntOfMinBits = IntOfMinSize<(bits + 7) / 8>
	Gives access to native integer types that hold at least k bits, where k may be any compile-time constant.

Functions
template<typename IntType >
constexpr int	regina::bitsRequired (IntType n)
	Returns the number of bits required to store integers in the range 0,...,n-1.
template<typename IntType >
constexpr IntType	regina::nextPowerOfTwo (IntType n)
	Returns the smallest integer power of two that is greater than or equal to the given argument n.

Variables
template<typename T >
constexpr bool	regina::is_cpp_integer_v = std::is_integral_v<T>
	A compile-time boolean constant that indicates whether the type T is a native C++ integer type, allowing for 128-bit integers also.
template<typename T >
constexpr bool	regina::is_unsigned_cpp_integer_v
	A compile-time boolean constant that indicates whether the type T is an unsigned native C++ integer type, allowing for 128-bit integers also.
template<typename IntType , IntType coeff>
constexpr IntType	regina::maxSafeFactor
	The largest integer of the given type that can be multiplied by coeff without overflowing.
template<typename IntType , IntType coeff>
constexpr IntType	regina::minSafeFactor
	The largest integer of the given type that can be multiplied by coeff without overflowing.

Detailed Description

Miscellaneous utility classes for analysing the built-in integer types at compile time.

Macro Definition Documentation

INT128_AVAILABLE

#define INT128_AVAILABLE

Defined if and only if native 128-bit arithmetic is available on this platform.

If this macro is defined, then you can access native signed and unsigned 128-bit integers through the types IntOfSize<16>::type and IntOfSize<16>::utype respectively.

If this macro is not defined, then the types IntOfSize<16>::type and IntOfSize<16>::utype will both be void.