Range policies

Range policies#

A range policy is any class that provides an interface similar to the following class:

template<typename OutputElement, typename... InputElement>
class RangePolicy
{
    public:

        auto within_range(InputElement const... value, OutputElement const result) -> bool;
};

The policy is used to check whether an algorithm’s result can be represented by the output element’s type. For example, when adding two large integral numbers, the result may end up being not representable by the output element’s type. In that case within_range should return false.

The lue::policy::AllValuesWithinRange policy is special in that it will assume all output element values to be representable by the output element type. This policy can be used when it is guaranteed that this is the case. An optimizing compiler will completely remove the “check” from the code.

template<typename OutputElement, typename ...InputElement>
class AllValuesWithinRange#

Output range policy that does nothing.

Use this policy if you do not want to check for “out-of-rangeness” in the output

Template Parameters:

  • OutputElement – Type of the output element

  • InputElement – Types of the input elements

Public Static Functions

static inline constexpr auto within_range([[maybe_unused]] InputElement const... value, [[maybe_unused]] OutputElement const result) -> bool#

Return whether all element value (s) are within the range.

This function always returns true.

Parameters:

result – Result value

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