On Mon, 22 Nov 2021 at 21:31, Mary Ann Horton <mah@mhorton.net> wrote:
PL/I was my favorite mainframe programming language my last two years as
an undergrad. I liked how it incorporated ideas from FORTRAN, ALGOL, and
COBOL. My student job was to enhance a PL/I package for a History professor.

What language were the PL/I compilers written in?

Wikipedia claims that IBM is still developing a PL/I compiler, which I suppose I have no reason to disbelieve, but I'm very curious as to who is using it and for what purpose.

-Henry