Function to_string_width

libs/base/string_utils.hpp:670–677

// Get string with fixed width. Extra '0' are added at the begining to fit size.
template <typename T, typename = std::enable_if_t<std::is_integral<T>::value>>
std::string to_string_width(T l, int width)
{
  std::ostringstream ss;
  if (l < 0)
    ss << '-';
  ss << std::setfill('0') << std::setw(width) << std::abs(l);
  return ss.str();
}

template <typename IterT1, typename IterT2>
bool StartsWith(IterT1 beg, IterT1 end, IterT2 begPrefix, IterT2 endPrefix)