// Converts: some/path/to/file.xx
// to: file
// (note that suffix is removed)
string GetFilename(StringPiece path);

// Converts:
//   cc/ops/gen_foo_ops.h
// to:
//   CC_OPS_GEN_FOO_OPS_H_
string ToGuard(StringPiece path);

// Converts: some_name_xyz
// to: Some Name Xyz
string ToTitle(StringPiece name);

// Change:     Into:
//   ABC         /// ABC
//               ///
//   DEF         /// DEF

  size_t slash_pos = path.rfind('/');
  if (slash_pos == path.npos) slash_pos = -1;
  size_t dot_pos = path.rfind('.');
  return string(path.substr(slash_pos + 1, dot_pos - (slash_pos + 1)));
}

string ToGuard(StringPiece path) {
  string guard;
  guard.reserve(path.size() + 1);  // + 1 -> trailing _
  for (const char c : path) {
    if (c >= 'A' && c <= 'Z') {
      guard += c;
    } else if (c >= 'a' && c <= 'z') {