Boost C++ Libraries

...one of the most highly regarded and expertly designed C++ library projects in the world. — Herb Sutter and Andrei Alexandrescu, C++ Coding Standards

Clear the contents.

void
clear() noexcept;

Erases all characters from the string. After this call, size() returns zero but capacity() is unchanged.

Linear in size().

All references, pointers, or iterators referring to contained elements are invalidated. Any past-the-end iterators are also invalidated.