Yes I meant APL, not PAL. By functional closures, I tried to mean functions as first-class objects, i.e. ability to pass them as arguments or store them in data structures, etc.

I had read this in an article about Ruby, AFAIK. It was talking about Ruby (or alternatively "Matz") borrowing many principles from LISP and there the author had mentioned Lisp's functions being first-class objects were adopted from APL. I should find that article to clear the things up.