Triangle - A bug or an extension?

[cpmachado]

Hello there,

During a code review with bomber34, as I'm quite new to Prolog, he pointed out the following(from my solution):

?- triangle(1.0, 1, 1).
false

This happens, because my solution which was similar to the example enforces type equality, and it shouldn't or should it?
I took the liberty to submit this patch, in case it's to be considered a bug.

Best regards,
cpmachado

[github-actions]

Hello. Thanks for opening a PR on Exercism 🙂

We ask that all changes to Exercism are discussed on our Community Forum before being opened on GitHub. To enforce this, we automatically close all PRs that are submitted. That doesn't mean your PR is rejected but that we want the initial discussion about it to happen on our forum where a wide range of key contributors across the Exercism ecosystem can weigh in.

You can use this link to copy this into a new topic on the forum. If we decide the PR is appropriate, we'll reopen it and continue with it, so please don't delete your local branch.

If you're interested in learning more about this auto-responder, please read this blog post.

---

Note: If this PR has been pre-approved, please link back to this PR on the forum thread and a maintainer or staff member will reopen it.

[ErikSchierboom]

I like this change, as it forces students to think about equality in Prolog.

My only suggestion would be is to add something to the docs to make students aware of this. The best way to do that is to add a .docs/instructions.append.md to the exercise, which could then make students aware (it'll get shown automatically in the editor and added to the instructions when downloaded via the CLI). See https://github.com/exercism/elixir/blob/main/exercises/practice/nth-prime/.docs/instructions.append.md for an example.

[cpmachado]

@ErikSchierboom My concern which wasn't maybe properly addressed, is that as my branch is, it enforces solutions without type equality. The implications are that many solutions that are currently working would be failing.
Should this change in tests be made as optional? as an extra task? bonus cookie, you know?

Going to address the requested change in the instructions append.

Looking forward for your reply :-)

[ErikSchierboom]

I'm looking into the test runner to see what happens when we mark a test as a bonus test, but unfortunately it does run them: exercism/prolog-test-runner#37

We run the tests with this command: https://github.com/exercism/prolog-test-runner/blob/main/bin/run.sh#L39:

swipl -f "${implementation_file}" -s "${tests_file}" -g run_tests,halt -t 'halt(1)' -- --all

Is there a way to ignore bonus tests?

[cpmachado]

I'll look into it later in the day, when I have time,

[cpmachado]

@ErikSchierboom Just fixed the tests and added the bonus flag as pending was before in 30debbe

To run bonus tests

swipl -f "${implementation_file}" -s "${tests_file}" -g run_tests,halt -t 'halt(1)' -- --bonus

[ErikSchierboom]

I was thinking of having the bonus tests be in a separate section, together at the end of the file. That way the student can slowly work through the required tests without getting involved in the bonus tests.

[cpmachado]

Good afternoon(GMT),
Yesterday in the evening I was checking the docs better, and as such we can improve this kind of approach with begin_tests/2.
I've done as you requested.
I did change the indentation, as the previous was getting on my nerves, I can revert that later.

I was just considering if we should just have pending condition, as I'm doing in bonus, for suites, instead of individual tests.

[cpmachado]

just linking this issue, apparently it is the last task #81

[cpmachado]

@ErikSchierboom Any more requests?

[ErikSchierboom]

Very nice! Thanks for being patient with me.