random_element.h

// Description: Random element in a range

#ifndef PASTELSYS_RANDOM_ELEMENT_H
#define PASTELSYS_RANDOM_ELEMENT_H

#include "pastel/sys/input/indexed_input_concept.h"
#include "pastel/sys/input/range_input.h"
#include "pastel/sys/random/random_integer.h"

#include <initializer_list>

namespace Pastel
{

    template <
        typename Indexed_Input,
        Requires<
            Models<Indexed_Input, Indexed_Input_Concept>
        > = 0>
    decltype(auto) randomElement(
        Indexed_Input input)
    {
        PENSURE_OP(input.n(), >, 0);
        return input[randomInteger(input.n())];
    }

    template <typename Type>
    decltype(auto) randomElement(
        const std::initializer_list<Type>& elementSet)
    {
        using Pastel::randomElement;
        return randomElement(rangeInput(elementSet));
    }

}

#endif