NAME¶

std::basic_string::pop_back - std::basic_string::pop_back

Synopsis¶

void pop_back(); (constexpr since C++20)

Removes the last character from the string.

Equivalent to erase(end() - 1). The behavior is undefined if the string is empty.

Parameters¶

(none)

Return value¶

(none)

Complexity¶

Constant.

Exceptions¶

Throws nothing.

Notes¶

In libstdc++, pop_back() is not available in C++98 mode.

Example¶

// Run this code

#include <cassert>
#include <iomanip>
#include <iostream>
#include <string>

int main()
{
std::string str("Short string!");
std::cout << "before=" << std::quoted(str) << '\n';
assert(str.size() == 13);

str.pop_back();
std::cout << " after=" << std::quoted(str) << '\n';
assert(str.size() == 12);

str.clear();
// str.pop_back(); // undefined behavior
}

Output:¶

before="Short string!"
after="Short string"

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 534 C++98 std::basic_string did not have the member added
function pop_back()

See also¶

push_back appends a character to the end
(public member function)
erase removes characters
(public member function)