delim.empty()) {
return ToString();
}
string_t result;
if (m_Data.empty()) {
return result;
}
// Hope we don't overflow the size type.
size_type st = (delim.size() * (m_Data.size() - 1)) + m_totalSize + 1;
result.reserve(st);
// If you need reasons to love C++11, here is one.
struct adder {
string_t m_Joiner;
adder(const string_t &s): m_Joiner(s) {
// This constructor is NOT empty.
}
// This functor runs under accumulate() without reallocations, if 'l' has reserved enough memory.
string_t operator()(string_t &l, const string_t &r) {
l += m_Joiner;
l += r;
return l;
}
} adr(delim);
auto iter = m_Data.begin();
// Skip the delimiter before the first element in the container.
result += *iter;
return std::accumulate(++iter, m_Data.end(), result, adr);
}
}; // class StringBuilder
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