Thanks for sharing, this is much better, though I actually think it is the perfect example to explain something that is brain-slippery about jq

look at $cols | $cols

my brain says hmm that's a typo, clearly they meant ; instead of | because nothing is getting piped, we just have two separate statements. Surely the assignment "exhausts the pipeline" and we're only passing null downstream

the pipelining has some implicit contextual stuff going on that I have to arrive at by trial and error each time since it doesn't fit in my worldview while I'm doing other shell stuff