template<class charT, class traits, class Allocator, class U = charT> constexpr typename basic_string<charT, traits, Allocator>::size_type erase(basic_string<charT, traits, Allocator>& c, const U& value);

Effects: Equivalent to: auto it = remove(c.begin(), c.end(), value); auto r = distance(it, c.end()); c.erase(it, c.end()); return r;

template<class charT, class traits, class Allocator, class Predicate> constexpr typename basic_string<charT, traits, Allocator>::size_type erase_if(basic_string<charT, traits, Allocator>& c, Predicate pred);

Effects: Equivalent to: auto it = remove_if(c.begin(), c.end(), pred); auto r = distance(it, c.end()); c.erase(it, c.end()); return r;