code: public final S parse(String string) {
          SequenceBuilder<S> builder = createBuilder().ensureCapacity(string.length());
          for (int i = 0; i < string.length(); ++i) {
              byte code = symbolToCode(string.charAt(i));
              if (code == -1)
                  throw new IllegalArgumentException("Letter \'" + string.charAt(i) + "\' is not defined in \'" + toString() + "\'.");
              builder.append(code);
          }
          return builder.createAndDestroy();
      }
docs: Parses string representation of sequence.
  
  @param string string representation of sequence
  @return sequence