Method substr

Bcore/src/main/cpp/base/stringpiece.h:195–199

  }

  StringPiece substr(size_type pos, size_type n = npos) const {
    if (pos > static_cast<size_type>(length_)) pos = length_;
    if (n > length_ - pos) n = length_ - pos;
    return StringPiece(ptr_ + pos, n);
  }

  int Compare(const StringPiece& rhs) const {
    const int r = memcmp(data(), rhs.data(), std::min(size(), rhs.size()));