std::deque<T,Allocator>::insert - cppreference.com (original) (raw)

Inserts elements at the specified location in the container.

1. Inserts a copy of value before pos.

If any of the following conditions is satisfied, the behavior is undefined:

• T is not CopyAssignable.

1. Inserts value before pos, possibly using move semantics.

2. Inserts count copies of the value before pos.

If any of the following conditions is satisfied, the behavior is undefined:

• T is not CopyAssignable.

1. Inserts elements from range [first, last) before pos.

1. Inserts elements from initializer list ilist before pos.

Equivalent to insert(pos, ilist.begin(), ilist.end()).

All iterators (including the end() iterator) are invalidated. References are invalidated too, unless pos == begin() or pos == end(), in which case they are not invalidated.

Contents

• 1 Parameters
• 2 Return value
• 3 Complexity
• 4 Exceptions
• 5 Example
• 6 Defect reports
• 7 See also

[edit] Parameters

[edit] Return value

1,2) Iterator pointing to the inserted value.

3-5) Iterator pointing to the first element inserted, or pos if no element is inserted.

[edit] Complexity

Linear in the number of elements inserted plus std::min(std::distance(begin(), pos), std::distance(pos, end())).

[edit] Exceptions

If an exception is thrown other than by

• the copy constructor of T,

• the copy assignment operator of T,

this function has no effect (strong exception guarantee).

[edit] Example

#include #include #include #include   namespace stq { void println(std::string_view rem, const std::deque& container) { std::cout << rem.substr(0, rem.size() - 2) << '['; bool first{true}; for (const int x : container) std::cout << (first ? first = false, "" : ", ") << x; std::cout << "]\n"; } }   int main() { std::deque c1(3, 100); stq::println("1. {}", c1);   auto pos = c1.begin(); pos = c1.insert(pos, 200); // overload (1) stq::println("2. {}", c1);   c1.insert(pos, 2, 300); // overload (3) stq::println("3. {}", c1);   // reset pos to the begin: pos = c1.begin();   std::deque c2(2, 400); c1.insert(std::next(pos, 2), c2.begin(), c2.end()); // overload (4) stq::println("4. {}", c1);   int arr[] = {501, 502, 503}; c1.insert(c1.begin(), arr, arr + std::size(arr)); // overload (4) stq::println("5. {}", c1);   c1.insert(c1.end(), {601, 602, 603}); // overload (5) stq::println("6. {}", c1); }

Output:

1. [100, 100, 100]
2. [200, 100, 100, 100]
3. [300, 300, 200, 100, 100, 100]
4. [300, 300, 400, 400, 200, 100, 100, 100]
5. [501, 502, 503, 300, 300, 400, 400, 200, 100, 100, 100]
6. [501, 502, 503, 300, 300, 400, 400, 200, 100, 100, 100, 601, 602, 603]

[edit] Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

[edit] See also