gplib/include/gp/algorithm/move.hpp

#pragma once

#include "gp/algorithm/tmp_manip.hpp"
#include "gp/range.hpp"

namespace gp{
	template<typename T>
	typename gp::remove_reference<T>::type&& move(T&& value)
	{
		return (typename gp::remove_reference<T>::type&&)value;
	}

	template<typename T> 
	constexpr T&& forward(typename gp::remove_reference<T>::type& t) noexcept
	{
		return static_cast<T&&>(t);
	}
	template<typename T> 
	constexpr T&& forward(typename gp::remove_reference<T>::type&& t) noexcept
	{
		static_assert(!std::is_lvalue_reference_v<T>,"bad forward of rvalue as lvalue");
		return static_cast<T&&>(t);
	}

	template<typename T>
	constexpr void swap(
		T& lhs,
		T& rhs
	)
	{
		auto tmp = lhs;
		lhs = rhs;
		rhs = tmp;
	}

	template<typename T>
	constexpr void swap(
		T&& lhs,
		T&& rhs
	)
	{
		auto tmp = lhs;
		lhs = rhs;
		rhs = tmp;
	}

	template<typename range_in, typename range_out>
	nameless_range<typename range_out::associated_iterator> move(range_in src, range_out dest)
	{
		if(src.size()>dest.size())
			return nameless_range<typename range_out::associated_iterator>(dest.begin(), dest.end());
		auto in = src.begin();
		auto in_close = src.end();
		auto out = dest.begin();
		while(in != in_close)
		{
			*(out++) = gp::move(*(in++));
		}
		return nameless_range<typename range_out::associated_iterator>{out, dest.end()};
	}

	template<typename range_in, typename range_out>
	nameless_range<typename gp::remove_reference<range_out>::type::associated_iterator> move_uninitialized(range_in&& src, range_out&& dest)
	{
		using T = typename gp::remove_reference<decltype(*dest.begin())>::type;
		if(src.size()>dest.size())
			return nameless_range<typename gp::remove_reference<range_out>::type::associated_iterator>(dest.begin(), dest.end());
		auto in = src.begin();
		auto in_close = src.end();
		auto out = dest.begin();
		while(in != in_close)
		{
			new(&*(out++)) T{gp::move(*(in++))};
		}
		return nameless_range<typename gp::remove_reference<range_out>::type::associated_iterator>{out, dest.end()};
	}
}