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Wow, that was a trip down memory lane! I have used six of those languages: BASIC, APL, COBOL, Pascal, Algol-W (a derivative of Algol 60), PL/1. Mostly in school. My first dollars earned in software (brief consulting gig in grad school) had me debug a PL/1 program for a bank.

For some reason I remember an odd feature of PL/1: Areas and offsets. If I am remembering correctly, you could allocate structures in an area and reference them by offset within that area. That stuck in my mind for some reason, but I never found a reason to use it. It struck me as a neat way to persist pointer-based data structures. And I don't remember seeing the idea in other languages.

Maybe the reason it stayed with me is that I worked on Object Design's ObjectStore. We had a much more elegant and powerful way of persisting pointer-based structures, but an area/offset idea could have given users some of the capabilities we provided right in the language.

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>> An area is a region in which space for based variables can be allocated. Areas can be cleared of their allocations in a single operation, thus allowing for wholesale freeing. Moreover, areas can be moved from one place to another by means of assignment to area variables, or through input-output operations. >> Based variables are useful in creating linked data struc tures, and also have applications in record inputoutput. A based variable does not have any storage of its own; instead, the declaration acts as a template and describes a generation of storage.