... https://pastebin.mozilla.org/8840197 (minor improvement/fixes to the opened_/closed_file package; dang OCD-ish itch.)
If you're talking the closed/open file thing, possibly... if the tasks/POs no [IMO].
The former would force a *LOT* of generics all over the place, along with a lot of the logic (which previously was done via subprograms and/or exceptions) pushed into the realm of the type. (Such would be useful for proving, like SPARK, but I think the resultant changes in the program composition would outweigh the benefit.)
^-- ESPECIALLY when you consider SPARK can do that sort of checking w/o forcing such a huge re-archetecting of the program.