I used to dream about owning a programmable calculator in the late 70s/early 80s, but by 1980 we had Apple ][s in my high school and in 1982, I was able to use the PCs in college, first programming in BASIC and later Turbo Pascal, which was the best PC development tool in the 1980s. Most of my classes were in Pascal. My first job was in C++ and I was doing C++ by 1993 and still am.

Now I write Python for fun.

Which model of HP calculator?

And what kinds of programs could you write with it?

I thought this was a good read, and it’s clearly a problem in an OO language, but I struggled to see how it’s an actual problem in a functional language. Maybe I need to go read that paper he referenced by the Racket guys.

Yeah, I never got around to writing a GC for Ur-Scheme either—you could argue that it's also "half-finished" but it does successfully compile itself correctly. It's not so much the GC that matters as it is the ability to allocate on the heap without much ceremony. I should have thought of that before I posted, and I appreciate the correction.

"Generic functions" is the Common Lisp name for writing a separate method for each class, the same as in Python except that you also have to define the generic function itself before you can define the methods. I'm not sure if that's what you meant; the ML approach is quite different.

This is Common Lisp, which I am not an expert in:

    ;;; Stupid CLOS example.

    (defgeneric x (point))                  ; make X a method
    (defgeneric y (point))                  ; make Y a method

    (defclass rect-point ()
      ((x :accessor x :initarg :x)
       (y :accessor y :initarg :y)))

    (defclass polar-point ()
      ((radius :accessor radius :initarg :radius)
       (angle  :accessor angle  :initarg :angle)))

    (defmethod x ((p polar-point))
      (* (radius p) (cos (angle p))))

    (defmethod y ((p polar-point))
      (* (radius p) (sin (angle p))))

    (defgeneric move-by (point Δx Δy))

    (defmethod move-by ((p rect-point) Δx Δy)
      (incf (x p) Δx)
      (incf (y p) Δy))

    (defmethod move-by ((p polar-point) Δx Δy)
      (let ((x (+ (x p) Δx)) (y (+ (y p) Δy)))
        (setf (radius p) (sqrt (+ (* x x) (* y y)))
              (angle p) (atan y x))))

    (defmethod print-object ((p polar-point) stream) ; standard method print-object
      (format stream "@~a<~a" (radius p) (angle p)))

    (defvar p1 (make-instance 'rect-point :x 3 :y 4))
    (defvar p2 (make-instance 'polar-point :radius 1 :angle 1.047))

    ;; prints (3, 4) → (4, 5)
    (format t "(~a, ~a) → " (x p1) (y p1))
    (move-by p1 1 1)
    (format t "(~a, ~a)~%" (x p1) (y p1))

    ;; prints @1<1.047 (0.500171, 0.8659266) → @1.9318848<0.7853087 (1.366171, 1.3659266)
    (format t "~a (~a, ~a) → " p2 (x p2) (y p2))
    (move-by p2 .866 .5)
    (format t "~a (~a, ~a)~%" p2 (x p2) (y p2))

    (* Stupid OCaml example. *)

    type point = Rect of float * float | Polar of float * float

    let x = function
      | Rect(x, y) -> x
      | Polar(r, theta) -> r *. Float.cos theta

    let y = function
      | Rect(x, y) -> y
      | Polar(r, theta) -> r *. Float.sin theta

    let moved_by = fun dx dy ->
      function
      | Rect(x, y) -> Rect(x +. dx, y +. dy)
      | p ->
         let x = dx +. x p and y = dy +. y p in
         Polar(Float.sqrt(x *. x +. y *. y),
               Float.atan2 y x)

    let string_of_point = function
      | Rect(x, y) -> Printf.sprintf "Rect(%f, %f)" x y
      | Polar(r, theta) -> Printf.sprintf "Polar(%f, %f)" r theta

    ;;

    print_endline(string_of_point(moved_by 1. 2. (Rect(3., 4.)))) ;
    print_endline(string_of_point(moved_by 0.866 0.5 (Polar(1., 1.047))))

Yes.

And B evolved from BCPL:

https://en.m.wikipedia.org/wiki/BCPL

I had read the book about BCPL by Martin Richards, creator of the language. it was quite interesting. IIRC, after describing the language, he gave some examples of small system software routines or utilities, written in it.

https://en.m.wikipedia.org/wiki/Martin_Richards_(computer_sc...

Fast to compile. It was very fast comparing to the others then. Since computers were slow (8086/80286) compiling speed actually mattered.

https://www.pcengines.ch/tp3.htm

Well given that often the alternative was BASIC which was interpreted, it also felt fast to run..