Anonymní profil Stamp – Programujte.com

 >>> stack.h

#pragma once
#include <iostream>
#include <vector>

template <typename T>
class Stack {
public:
	using value_type 	  = T;
	using reference		  = T & ;
	using const_reference = const T &;

	Stack() = default;
	Stack( std::initializer_list<T> list )
		: m_size( list.size() )
	{
		m_buffer.reserve( m_size );
		for ( auto& item : list ) { m_buffer.push_back( item ); } 
	}

	template <typename Arg>
	Stack( std::size_t count, Arg&& args )
		: m_size( count ) 
	{
		for ( int i = 0; i < count; ++i ) { m_buffer.push_back( std::forward<Arg>( args ) ); }
	}

	Stack( const Stack& ) = default;
	Stack( Stack&& ) = default;
	Stack& operator=( const Stack& ) = default;
	Stack& operator=( Stack&& ) = default;

	template <typename Arg>
	void push( Arg&& args ) {
		++m_size;
		m_buffer.push_back( std::forward<Arg>( args ));
	}

	template <typename Arg> 
	void emplace( Arg&& args ) {
		++m_size;
		m_buffer.emplace_back( std::forward<Arg>( args ) );
	}

	void swap( Stack<T>& other ) {
		using std::swap;
		std::swap( m_buffer, other.m_buffer );
		std::swap( m_size, other.m_size );
	}

	void pop() {
		if ( !empty() ) {
			--m_size;
		}
	}

	reference top()		    { return _top( *this ); }
	const_reference top() const { return _top( *this ); }

	bool empty() const { return m_size == 0; }
	std::size_t size() const { return m_size; }

private:
	std::vector<T> m_buffer;
	std::size_t m_size = 0;

	template < typename Self >
	auto& _top( Self& self ){
		if ( self.empty() ) {
		        throw std::logic_error::logic_error( "Calling top on empty stack!" );
		}
		return self.m_buffer[ self.m_size - 1 ];
	}
};

 >>> main.cpp

#include <iostream>
#include "stack.h"
int main()
{
	const Stack<int> stack2 {2};
	auto y = stack2.top();
}

 Pokial tam nemam static tak v MSVC dostanem nieco taketo:

Error	C2662	'auto &Stack<int>::_top<const Stack<int>>(Self &)': cannot convert 'this' pointer from 'const Stack<int>' to 'Stack<int> &' 57	

EDIT: Samozrejme myslim static auto& top

Ahoj, snazim sa vyriesit duplikaciu kodu v const/non-const verzii pri mojej implementacii metody top() v triede stack s vyuzitim sablon, avsak toto sa mi neskompiluje pokial tam nepridam staticauto& _at .. moc nerozumiem preco, nejake vysvetlenie ? dakujem :-)
 

reference top() {
	return _top( *this );
}
const_reference top() const {
	return _top( *this );
}


template < typename Self >
auto& _top( Self& self ){
	if ( self.empty() ) {
		throw std::logic_error::logic_error( "Calling top on empty stack!" );
	}
	return self.m_buffer[ self.m_size - 1 ];
}