Algol (1960s) had no garbage collection (that I know of), so any "closure-like" data captured by a function/procedure reference had to still be on the call stac

Algol (1960s) had no garbage collection (that I know of), so any "closure-like" data captured by a function/procedure reference had to still be on the call stack. Otherwise, you certainly had first class functions, just not always with any external state captured. https://en.wikipedia.org/wiki/Man_or_boy_test https://en.wikipedia.org/wiki/Man_or_boy_test I suspect TurboPascal was in the "boy" camp, in that a reference to a function (or procedure) would not have any external state bound to it.