According to the Picat developers, SETL was the first language with list comprehensions. Neat!
I have fond memories of looking at SETL when I wrote my thesis, but didn’t know about the list comprehension thing. That’s cool! The only language I know of that uses sets in a similar way before SETL is MADCAP, described in Sammet’s book. Kinda sad I didn’t notice this back in my grad school days.
Many of the old links for the SETL family of implementations are broken. I’m attempting to collect and preserve as much of the history of the project as I can. Here is the source code to SETL2, SETL-2, and ISETL. Still to come: the original SETL, and documents such as the SETL Newsletter series. If you have information, I’d love to hear from you.
Unfortunately I don’t have any of these. It seems the Internet Archive has some documents hosted. Wish I had more to offer than that :/