STM internally side-effecting thing. Stream processing over I/O is also side effecting thing. The point is that one should not mix and match arbitrary stream pr

STM internally side-effecting thing. Stream processing over I/O is also side effecting thing. The point is that one should not mix and match arbitrary stream processing with arbitrary STM transactions. One should have control over when and where and compiler should prevent incorrect use (just like with borrow checker).