C++ 如何按索引设置 std::tuple 元素？
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How to set std::tuple element by index?
提问by Behrouz.M
One can get an element from std::tupleby index using std::get.
Analogically, how to settuple's element by index?
可以std::tuple使用std::get. 类似地，如何通过索引设置元组的元素？
回答by Nicol Bolas
std::getreturns a reference to the value. So you set the value like this:
std::get返回对值的引用。所以你设置这样的值：
std::get<0>(myTuple) = newValue;
This of course assumes that myTupleis non-const. You can even move items out of a tuple via std::move, by invoking it on the tuple:
这当然假设它myTuple是非常量的。您甚至可以通过std::move在元组上调用它来将项目移出元组：
auto movedTo = std::get<0>(std::move(myTuple));
回答by amit
The non-const version of getreturns a reference. You can assign to the reference. For example, suppose tis tuple, then: get<0>(t) = 3;
的非常量版本get返回一个引用。您可以分配给参考。例如，假设t是元组，则：get<0>(t) = 3;
