```python
[ins] In [38]: regarray = Signal(ArrayLayoutND(8, 4, 4))

[nav] In [39]: regarray[2:, 1].eq(regarray[:2, 0])
Out[39]: (eq (cat (slice (sig regarray) 72:80) (slice (sig regarray) 104:112)) (cat (slice (sig regarray) 0:8) (slice (sig regarray) 32:40)))
```
would this be something useful to upstream or should it remain in my utils.py