A shell in Rust could be really cool

Ah, thanks for that explanation, it makes sense, and adds one more thing to the list of gotchas for me to keep in mind with shell code . . .

I try to use unix timestamps ($(date +%s)) whenever I'm dealing with times and dates of any sort in shell scripts, and then use $(date -d @...) to convert to something human readable - not particularly portable, but I'm fortunate enough to only really deal with Linux systems (aside from an occasional Mac, which has caused me serious headaches at times).

I do sometimes use sub-second precision (e.g. $(date +%s.%N)) for higher resolution timing, which then necessitates using bc -l or similar for any calculations. That recently bit me, in combination with scoping issues - I was mixing second and sub-second precision and the (perfectly logical) variable name 'now', and getting errors from arithmetic expansions when a sub-second precision value was still active where I thought it should be second precision . . . Fixing that just required fixing the scoping and naming issues ('local' is one of my favourite keywords), but it took *far* to long to spot the bug.

And to bring this back on topic, that's one monstrosity of a shell script that *absolutely* needs to be rewritten - though probably not in Rust, sadly, since I'm the only person in my team who'd have any hope of working on a Rust version . . .