And that came from Emacs and old Lisp environments---and perhaps something yet earlier?
As late as 2000, this was the single biggest advantage and single biggest impediment to new programmers in MIT's 6.001 lab: a bunch of nonvisible state, mutated by every C-x C-e. The student has tweaked two dozen points trying to fix a small program, and re-evaluated definitions after many of them, but maybe not all. The most straightforward help from a teacher is to get the buffer into a form such that M-x eval-region paves over all that, sets a known environment of top level definitions, and---more than half the time---the student's code now works.
I have similar concerns about much of Victor's work, for the same reason. Managing a mental model of complex state is a n important skill for programming, but it's best learned incrementally over long experience with more complex programs. These very interactive environments front load the need for that skill without giving any obvious structure for helping the student learn.
Contrast Excel and HyperCard, which have no invisible state: you can click and see everything.
As late as 2000, this was the single biggest advantage and single biggest impediment to new programmers in MIT's 6.001 lab: a bunch of nonvisible state, mutated by every C-x C-e. The student has tweaked two dozen points trying to fix a small program, and re-evaluated definitions after many of them, but maybe not all. The most straightforward help from a teacher is to get the buffer into a form such that M-x eval-region paves over all that, sets a known environment of top level definitions, and---more than half the time---the student's code now works.
I have similar concerns about much of Victor's work, for the same reason. Managing a mental model of complex state is a n important skill for programming, but it's best learned incrementally over long experience with more complex programs. These very interactive environments front load the need for that skill without giving any obvious structure for helping the student learn.
Contrast Excel and HyperCard, which have no invisible state: you can click and see everything.