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Comment by int_19h | Hacker News Reader

Nice to see turtle graphics mentioned in this context. Back when I learned to code, it was one of the more common teaching techniques, and I still believe that it's one of the most "hands on" ways to explain loops, recursion etc.

As far as development environments - have you tried Thonny (https://thonny.org/)? It has some nice features in it that are specifically geared towards explaining how things work. For example, when you debug, you can step through subexpressions, and their values are automatically substituted in the editor as they are computed.

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I might be odd here, but my intro to Python was with turtle graphics and I despised it. My spatial sense is rather poor, and having to translate between code and Cartesian coordinates and vice versa was a heavy mental overhead.

    for x in range(0, 10):
        print(x)

Is way clearer to me than having to draw circles or lines and then manually calculating the Cartesian coordinates I should have hit to make sure it's actually doing what I want.

Likewise with pretty much all of the constructs. It's easy to understand a function that sums a list of ints, and it's easy to check. It's much harder for me to grok and check a function that draws circles at a list of Cartesian coordinates. A recursive Fibonacci sequence is easy for me to grok; just have it print out the values it's using at each loop. A recursive function to draw fractals is going to take me forever to figure out what recursion is actually doing. I can see that it changes, but figuring out how/why or why I would ever want to use it is really difficult.

I think it's just too much of an abstraction for me. Code -> numbers -> coordinates -> image is too many indirections for me to follow. When I wanted something "hands on", I usually defaulted to consuming APIs. It's really not much harder to install a Reddit API client and use it. It gives me something I can check, it's something I would actually want to do, and it's practically infinitely extensible.

I'm not quite sure I follow; isn't the whole point of turtle graphics to not have to think about Cartesian coordinates, but rather in terms of "move that far" and "turn that much" (at least initially)?

Or do you mean the other way around, as in, you start with an image of the end result in your head that's defined in terms of coordinates, and then you had to write the move/turn code that achieves that? I can see how that would be quite frustrating; but if you are already thinking in coordinates throughout, then you don't need the "turtle" part anymore - but you can still do graphics.

I've never taught turtle graphics in python, but in Logo, Cartesian coordinates are seldom used. It's mostly relative movement, which is far more intuitive

What age were you introduced to Python?

Explaining what range() does to elementary age children seems interesting.

For the first approximation, you can simply explain it as part of the for-statement syntax. When you get to lists and iterating over them, this simple approach breaks, but by then you can redefine it as a kind of list.

Once you have explained iterators - and I don't mean the nitty gritty of __iter__(), next() etc, but rather the high-level notion of a function that yields multiple values to the caller, the true meaning of range() is easily explained in those terms.

Back in the 80s I took a summer school class offered by the district in 'computer programming' which was about half logo half applesoft basic. The school even had a little 'turtlebot' driving pen plotter bot, tethered to one of the //e's by what I assume was a serial cable.

If your logo program was particularly cool the teacher would print your program out on the little dot matrix printer and project it up on a screen using an opaque projector and step through it line by line while the little robot drew it out on a piece of butcher paper.

Probably one of the early experiences that made me love pen plotters.

Thonny looks great, thanks for the tip! I've had friends who had trouble understanding how return values work, this would help!

That's a nice way to show functional programming as well: by showing the inside-out nature of transformations of input.

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