std::basic_string<CharT,Traits,Allocator>:: push_back

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void push_back ( CharT ch ) ;
(constexpr since C++20)

Appends the given character ch to the end of the string.

Parameters

ch - the character to append

Return value

(none)

Complexity

Amortized constant.

Exceptions

If the operation would result in size ( ) > max_size ( ) , throws std::length_error .

If an exception is thrown for any reason, this function has no effect ( strong exception safety guarantee ).

Example

#include <iomanip>
#include <iostream>
#include <string>
 
int main()
{
    std::string str{"Short string"};
    std::cout << "1) " << std::quoted(str) << ", size: " << str.size() << '\n';
 
    str.push_back('!');
    std::cout << "2) " << std::quoted(str) << ", size: " << str.size() << '\n';
}

Output:

1) "Short string", size: 12
2) "Short string!", size: 13

Defect reports

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

DR Applied to Behavior as published Correct behavior
LWG 7 C++98 1) the description was missing in the C++ standard
2) the parameter type was const CharT
1) description added
2) changed to CharT
LWG 847 C++98 there was no exception safety guarantee added strong exception safety guarantee

See also

( DR* )
removes the last character
(public member function)