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std::nothrow

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< cpp‎ | memory‎ | new
 
 
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Defined in header <new>
extern const std::nothrow_t nothrow;

std::nothrow is a constant of type std::nothrow_t used to disambiguate the overloads of throwing and non-throwing allocation functions.

[edit] Example

#include <iostream>
#include <new>
 
int main()
{
    try {
        while (true) {
            new int[100000000ul];   // throwing overload
        }
    } catch (const std::bad_alloc& e) {
        std::cout << e.what() << '\n';
    }
 
    while (true) {
        int* p = new(std::nothrow) int[100000000ul]; // non-throwing overload
        if (p == nullptr) {
            std::cout << "Allocation returned nullptr\n";
            break;
        }
    }
}

Output:

std::bad_alloc
Allocation returned nullptr

[edit] See also

tag type used to select an non-throwing allocation function
(class) [edit]
allocation functions
(function) [edit]