Type alias (seit C++11) – cppreference.com

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Typ-Aliasnamen ähneln typedefs, haben jedoch den Vorteil, mit Schablonen .

Original:

Type aliases are similar to typedefs, however, have the advantage of working with templates.

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Syntax


`using` identifier `=` type_name`;`

Beispiele

using flags = std::ios_base::fmtflags;
using func = void (*) (int,int);
// typedef std::ios_base::fmtflags flags;
// typedef void (*func)(int, int);

template<class T> using ptr = T*;
ptr<int> x;

template<class T> using vec = std::vector<T>;
vec<float> w;

// type alias used to hide some template parameter 
template<class CharT> using mystring = std::basic_string<CharT,std::char_traits<CharT>>;
mystring<char> str;

// type alias used to simplify the syntax of std::enable_if
template< class Condition >
using EnableIf = Invoke<std::enable_if<Condition::value>>;

template <typename T, typename = EnableIf<std::is_polymorphic<T>>>
int f(T t);