Clojurians Log v2

@slipset then I hope she is doing better then me . I did now some 12 and im very stuck at solving the rest

a question

Im now busy with the space_age challenge But I wonder what is the best way to link planets to a factor. So I can use the factor in a calculation

I think that is the one which makes sense to use a macro, actually

oke, then I have to dive into macros

Because the tests expect you to have a function for calculating the time on each planet

(a function for each planet)

yep , I see that when I open the challenge. I see a lot of methods. One for every planet

but I mean more how to store the planet name and the factor

I mean... you could write 9 different functions, but using a macro makes it so you only have to write one

Another way I've seen that avoids macros, and also avoids having to write 9 functions, is to use intern: https://clojuredocs.org/clojure.core/intern With that, you can pass a namespace, symbol name, and function body and will define the appropriate function

What does this vague error message mean ;

An unexpected error occurred:
sci.impl.fns$fun$arity_0__1162 cannot be cast to java.lang.Number

(defn seconds_year_earth
  []
  31557600
 )

 (defn conversion_ratios
   "returns the factor for the seconds a year for a planet"
   [planet]
    {
     :mercury 0.2408467 
     :venus  0.61519726 
    }
   )

(defn on-earth 
  [seconds]
  (/ seconds seconds_year_earth))

(defn on-mercury 
  [seconds]
  (*(on-earth seconds)  (conversion_ratios :mercury)))

A thing that we both find difficult is the numbers stuff. It’s quite mathy, especially for a 13 year old (who might not be the target audience) but also for a 50something who’s forgotten most of his maths.

I really enjoyed the robot thingy. It sounds really complicated when reading but we managed to make a rather neat solution with reduce

The cool thing with doing it with reduce was that on first go we got the wrong answer (we did the exercise on paper first), so we switched to reductions and could see exactly where we’d done the mistake.

oke, I was stuck at the age-planet challenge but with some help of this channels I think I found a way to solve things

With the robot thing , you mean the robot-name or the robot-simulator challenge ?

I know the feeling with maths. Im 56 and math at school I was fairly good at

@slipset

One project I've been planning is a gentle maths course using Clojure for young people, or older folks who have either forgotten or never learned it in the first place, like me

I'm not sure if this would be a fit for Exercism though. They tried to do something similar in the Julia track, but it was never finished.

Jeremy, the CEO, said that it wasn't likely to be viable because it strayed too far from the pedagogical style that Exercism uses. As I recall it involved the student building up over several exercises, a mini maths library. But this is something that I'm going to build in any case, because I think it's really important.

Again, perhaps not the target audience, but the language of the exercises seem a bit theoretical for my 13 year old. Like, on strings, > A string in Clojure is a Java string, which is an object that represents immutable text as a sequence of Unicode characters (letters, digits, punctuation, etc.) and is defined as follows: is the introduction. There were so many questions asked when she read this sentence. Also, IMO, so much information here that she didn’t need in order to do the exercises or to learn about strings. Please do tell me to shut up if I’m rambling about stuff that is not interesting.

The feedback is much appreciated 🙂 The target audience of Exercism is indeed people who have experience in at least one other language

🙂 My daughter started on the Python track, but I got tired of the whitespace stuff and switched her over to Clojure 🙂

So I guess she has “experience” in at least one other language.

For awhile they were kicking around an idea for a whole new "Learn to Code" platform to address this gap

But, she is really enjoying this, and she’s working on the problems on her own, and I get to help her. So my comments are mostly nitpicks.

She’s also found an online Clojure repl where she tries out her solutions when the tests don’t pass 🙂

I wrote a REPL plugin for the Exercism editor that uses SCI, but unfortunately it was never added to the site

I got a bit annoyed when she was working on the “bird watcher” because I suggested a solution like:

(defn inc-bird [birds]
  (conj (vec (butlast birds)) (inc (last birds))))

and I guess reaching for butlast should have been a sign for me to consider another solution 🙂

It was a challenge to port some of those exercises, because they were written for other languages and it was often awkward to make it work in Clojure without totally reworking them

Anyways, thanks for the work you’re putting in. As I said, Una is really enjoying this, and it’s really fun to work with her on them.

That's great to hear 🙂