message: Add line which went missing.
diff: @@ -66,6 +66,7 @@ class Coo;
  template <typename ValueType = default_precision, typename IndexType = int32>
  class Csr : public BasicLinOp<Csr<ValueType, IndexType>>,
  public ConvertibleTo<Dense<ValueType>>,
  + public ConvertibleTo<Coo<ValueType, IndexType>>,
  public ReadableFromMtx,
  public Transposable {
  friend class BasicLinOp<Csr>;
  