std::inplace_vector<T,N>::assign

 

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std::inplace_vector

Member types
Member functions
inplace_vector::inplace_vector inplace_vector::~inplace_vector    inplace_vector::operator= inplace_vector::assign inplace_vector::assign_range Size and capacity inplace_vector::empty inplace_vector::size inplace_vector::max_size inplace_vector::capacity inplace_vector::resize inplace_vector::reserve inplace_vector::shrink_to_fit Iterators inplace_vector::begininplace_vector::cbegin inplace_vector::endinplace_vector::cend inplace_vector::rbegininplace_vector::crbegin inplace_vector::rendinplace_vector::crend	Element access inplace_vector::at inplace_vector::operator[] inplace_vector::front inplace_vector::back inplace_vector::data Modifiers inplace_vector::clear inplace_vector::erase inplace_vector::swap inplace_vector::insert inplace_vector::insert_range inplace_vector::emplace inplace_vector::emplace_back inplace_vector::try_emplace_back inplace_vector::unchecked_emplace_back inplace_vector::push_back inplace_vector::try_push_back inplace_vector::unchecked_push_back inplace_vector::pop_back inplace_vector::append_range inplace_vector::try_append_range
Non-member functions
erase(std::inplace_vector)erase_if(std::inplace_vector) swap(std::inplace_vector)	operator==operator<=>

 

constexprvoid assign( size_type count, const T& value );	(1)	(since C++26)
template<class InputIt > constexprvoid assign( InputIt first, InputIt last );	(2)	(since C++26)
constexprvoid assign(std::initializer_list<T> ilist );	(3)	(since C++26)

Replaces the contents of the container.

1) Replaces the contents with count copies of value value.

2) Replaces the contents with copies of those in the range [first, last).

This overload participates in overload resolution only if InputIt satisfies the requirements of LegacyInputIterator.

If first or last is an iterator into *this, the behavior is undefined.

3) Replaces the contents with the elements from ilist.

Parameters

count	-	the new size of the container
value	-	the value to initialize elements of the container with
first, last	-	the pair of iterators defining the source range of elements to copy
ilist	-	std::initializer_list to copy the values from

Complexity

1) Linear in count.

2) Linear in distance between first and last.

3) Linear in ilist.size().

Exceptions

1)std::bad_alloc, if count > capacity().

2)std::bad_alloc, if ranges::distance(first, last)> capacity().

3)std::bad_alloc, if ilist.size()> capacity().

1-3) Any exception thrown by initialization of inserted elements.

Example

The following code uses assign to add several characters to a std::inplace_vector<char, 5>:

Run this code

#include <inplace_vector>#include <iterator>#include <new>#include <print>   int main(){std::inplace_vector<char, 5> chars;   chars.assign(4, 'a');// overload (1)std::println("{}", chars);   constchar extra[3]{'a', 'b', 'c'}; chars.assign(std::cbegin(extra), std::cend(extra));// overload (2)std::println("{}", chars);   chars.assign({'C', '+', '+', '2', '6'});// overload (3)std::println("{}", chars);   try{ chars.assign(8, 'x');// throws: count > chars.capacity()}catch(conststd::bad_alloc&){std::println("std::bad_alloc #1");}   try{constchar bad[8]{'?'};// ranges::distance(bad) > chars.capacity() chars.assign(std::cbegin(bad), std::cend(bad));// throws}catch(conststd::bad_alloc&){std::println("std::bad_alloc #2");}   try{constauto l ={'1', '2', '3', '4', '5', '6'}; chars.assign(l);// throws: l.size() > chars.capacity()}catch(conststd::bad_alloc&){std::println("std::bad_alloc #3");}}

Output:

['a', 'a', 'a', 'a'] ['a', 'b', 'c'] ['C', '+', '+', '2', '6'] std::bad_alloc #1 std::bad_alloc #2 std::bad_alloc #3

See also

assign_range	assigns a range of values to the container (public member function)
operator=	assigns values to the container (public member function)