Problem-specifications: Don't assume two-fer is the second exercise.

[Smarticles101]

Ref. exercism/bash#86

Don't assume two-fer is the second exercise. Remove the section on test driven development and maybe put it somewhere else? What is the consensus on this?

[Insti]

https://github.com/exercism/problem-specifications/blob/master/exercises/two-fer/description.md

The descriptions should only describe the task.

[rpottsoh]

I don't see how this is related to exercism/bash#68.

Another way to think about this. Hello-World is the 0th exercise. Its purpose is to help the student realize that their environment is properly setup and working correctly for the given track. This, in-turn, makes two-fer a good 1st exercise....

[petertseng]

I can surely say this: For the same reasons that I in https://github.com/exercism/problem-specifications/issues/520 recommend against old hello-world (roughly equivalent to two-fer) as the first exercise of at least the six tracks Elm, F#, Haskell, OCaml, Purescript, and Rust, I recommend against two-fer as the second exercise of those tracks. I am not a maintainer of all six tracks I named, but my recommendation remains.

Hello-World is the 0th exercise. Its purpose is to help the student realize that their environment is properly setup and working correctly for the given track.

I agree, because it contains the minimum that will be present in all further exercises (a test suite that tests some function) without introducing any logic in the tested function(s).

This, in-turn, makes two-fer a good 1st exercise....

I do not agree, because the previous statement (contains the minimum that will be present in all further exercises) is not true. Furthermore, depending on the track maintainers' decision, variable arities and/or option/maybe are not necessarily appropriate to be the first non-hello-world exercise.
Edit: The crossed-out reasoning is an incorrect argument, so I retract it. The remaining portion is my remaining argument that I stand by.

So, the "just after Hello World" at https://github.com/exercism/problem-specifications/blob/master/exercises/two-fer/metadata.yml#L3 seems to be too restrictive of the position of the exercise.

An interesting question to ask is: Is there any track that wishes to use two-fer as an exercise in any position other than second?

If there never will be any such track, there will be no contradiction to leave everything as-is; tracks either have two-fer second or not at all.

If there will be, then indeed "just after Hello World" would need to be removed, and any other changes y'all find necessary.

[Smarticles101]

sorry @rpottsoh you're right it doesn't relate to exercism/bash#68 I meant exercism/bash#86 I have edited the description to fix the error

[petertseng]

Here are the tracks that have two-fer, and two-fer's zero-indexed position in each:

gems/trackler-2.2.1.45$ for t in tracks/*; do ruby -rjson -e "i = JSON.parse(File.read('$t/config.json'))['exercises'].index { |e| e['slug'] == 'two-fer' }; puts '%20s: %d' % ['$t', i] if i"; done
         tracks/bash: 10
       tracks/csharp: 5
       tracks/delphi: 1
       tracks/erlang: 19
       tracks/factor: 2
       tracks/fsharp: 4
           tracks/go: 1
       tracks/groovy: 7
         tracks/java: 1
       tracks/python: 76
          tracks/sml: 1

[Insti]

Are you going to submit a PR for this @Smarticles101 ?

[Smarticles101]

@Insti yep, I can do that :)

[rpottsoh]

@Insti said:

The descriptions should only describe the task.

I agree with this in principle.

I see in #975 that the section of TDD has been removed. Is this information that should appear somewhere else? Does it already appear somewhere else? Since hello-world seems to be the defacto first exercise, should the removed text be incorporated there? If so how, in the README or the canonical data?

[petertseng]

Since hello-world seems to be the defacto first exercise, should the removed text be incorporated there?

If it did, it would revert https://github.com/exercism/problem-specifications/commit/35aa16b27b3f4a6ef958f5740d23648d9ec975ef#diff-607a2b1720cb33d38eae0ecd2272b67e and https://github.com/exercism/problem-specifications/pull/544 . If that is done, will the person who does that please provide the reason why it appropriate to add it back to hello-world, thank you

[Insti]

Tracks should decide:

a) The order of the exercises.
b) The content of their Readmes

If there needs to be a common version about TDD philosophy, this should probably be stored in the documentation repository.