An Implementation of the One Billion Row Challenge in Common Lisp

Boredom pours out of me.  I learned about this challenge, and decided to participate without reason:
https://www.morling.dev/blog/one-billion-row-challenge/

I figured, at the least, it could be mildly interesting to write Common Lisp and Ada implementations
to approach this silly little game.  The mentioned test machine has dozens of gigabytes of memories,
meaning even the simple one-line approach of something like APL would fit the challenge very easily.

I nearly got bored and stopped writing my Common Lisp version halfway, and decided to avoid anything
like writing multiple implementations.  Without such a powerful test machine, I'd be unable to see a
minor difference between implementations anyway.  Still, it's rather unbecoming to write Common Lisp
such as this which is unsuited to interactive error handling, so I used conditional inclusion reader
macros to enable this to be turned on or off, trivially.  Rather than use my TRIVIAL-TRIE library, I
instead only use a hash-table for mapping station names to their intermediate results.  Also, rather
than use any specialized temperature-reading logic, as PARSE-INTEGER works only for integers, I used
READ-LINE to make the problem easy.  I invite any interested reader to see how my function performs.
.