std::tie
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definiert in Header <tuple> | ||
template<class... Types> tuple<Types&...> tie( Types&... args); | (seit C++11) | |
Erstellt einen Tupel lvalue Verweise auf seine Argumente oder Instanzen von std::ignore .
Original:
Creates a tuple of lvalue references to its arguments or instances of std::ignore.
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Inhaltsverzeichnis |
[Bearbeiten]Parameter
| args | - | null oder mehr lvalue Argumente, um die Tupel aus zu bauen Original: zero or more lvalue arguments to construct the tuple from The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. |
[Bearbeiten]Rückgabewert
A
std::tuple Objekt mit lvalue referenes .Original:
A
std::tuple object containing lvalue referenes.The text has been machine-translated via Google Translate.
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[Bearbeiten]Ausnahmen
[Bearbeiten]Beispiel
std::tie können verwendet werden, um die Einführung lexikographische Vergleich zu einer Struktur oder ein Tupel auszupacken werden:
Original:
std::tie can be used to introduce lexicographical comparison to a struct or to unpack a tuple:
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#include <iostream>#include <string>#include <set>#include <tuple> struct S {int n;std::string s;float d;bool operator<(const S& rhs)const{// compares n to rhs.n,// then s to rhs.s,// then d to rhs.dreturn std::tie(n, s, d)< std::tie(rhs.n, rhs.s, rhs.d);}}; int main(){std::set<S> set_of_s;// S is LessThanComparable S value{42, "Test", 3.14};std::set<S>::iterator iter;bool inserted;// unpacks the return value of insert into iter and inserted std::tie(iter, inserted)= set_of_s.insert(value);if(inserted)std::cout<<"Value was inserted sucessfully\n";}
Output:
Value was inserted sucessfully
erzeugt eine tuple Objekt des Typs von den Argumenttypen definiertOriginal: creates a tuple object of the type defined by the argument typesThe text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (Funktions-Template) | |
erzeugt ein tuple aus rvalue ReferenzenOriginal: creates a tuple of rvalue referencesThe text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (Funktions-Template) | |
erzeugt ein tuple durch Verketten einer beliebigen Anzahl von TupelnOriginal: creates a tuple by concatenating any number of tuplesThe text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (Funktions-Template) | |
Platzhalter, um ein Element zu überspringen, wenn Auspacken einer tuple mit tieOriginal: placeholder to skip an element when unpacking a tuple using tieThe text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (konstanten) | |
