Class StringRef

Bcore/src/main/cpp/Dobby/tests/catch.hpp:391–469

A non-owning string class (similar to the forthcoming std::string_view) Note that, because a StringRef may be a substring of another string, it may not be null terminated. c_str() must return a null terminated string, however, and so the StringRef will internally take ownership (taking a copy), if necessary. In theory this ownership is not externally visible - but it does mean (substring) StringRe

/// visible - but it does mean (substring) StringRefs should not be shared between
/// threads.
class StringRef {
public:
  using size_type = std::size_t;

private:
  friend struct StringRefTestAccess;

  char const *m_start;
  size_type m_size;

  char *m_data = nullptr;

  void takeOwnership();

  static constexpr char const *const s_empty = "";

public: // construction/ assignment
  StringRef() noexcept : StringRef(s_empty, 0) {
  }

  StringRef(StringRef const &other) noexcept : m_start(other.m_start), m_size(other.m_size) {
  }

  StringRef(StringRef &&other) noexcept : m_start(other.m_start), m_size(other.m_size), m_data(other.m_data) {
    other.m_data = nullptr;
  }

  StringRef(char const *rawChars) noexcept;

  StringRef(char const *rawChars, size_type size) noexcept : m_start(rawChars), m_size(size) {
  }

  StringRef(std::string const &stdString) noexcept : m_start(stdString.c_str()), m_size(stdString.size()) {
  }

  ~StringRef() noexcept {
    delete[] m_data;
  }

  auto operator=(StringRef const &other) noexcept -> StringRef & {
    delete[] m_data;
    m_data  = nullptr;
    m_start = other.m_start;
    m_size  = other.m_size;
    return *this;
  }

  operator std::string() const;

  void swap(StringRef &other) noexcept;

public: // operators
  auto operator==(StringRef const &other) const noexcept -> bool;
  auto operator!=(StringRef const &other) const noexcept -> bool;

  auto operator[](size_type index) const noexcept -> char;

public: // named queries