Add Bracket Push Exercise

[lpalma]

Port Bracket Push to the Haskell Track.

For the Example Solution, I tried to explore Data constructors and the Maybe type.

[lpalma]

Not 100% sure it is difficulty 3. Perhaps I'm overcomplicating it?

[petertseng]

It's true that once one realizes one can use a stack, it is easy. So the hard part is not writing the implementation. It is figuring out how to tackle the problem at all.

Because of this, I would actually rate higher, maybe 4 or 5.

If it helps to see how other tracks rated it:

for i in tracks/*/config.json; do echo $i; jq 'if any(.exercises[]; .difficulty != 1) then .exercises | map(select(.slug == "bracket-push")) else [] end' < $i; done

tracks/ceylon/config.json
[
  {
    "slug": "bracket-push",
    "difficulty": 6,
    "topics": [
      "Parsing",
      "Stacks",
      "Strings"
    ]
  }
]

tracks/csharp/config.json
[
  {
    "slug": "bracket-push",
    "difficulty": 5,
    "topics": [
      "Parsing",
      "Strings"
    ]
  }
]

tracks/elixir/config.json
[
  {
    "slug": "bracket-push",
    "difficulty": 3,
    "topics": []
  }
]

tracks/fsharp/config.json
[
  {
    "slug": "bracket-push",
    "difficulty": 7,
    "topics": [
      "Parsing",
      "Strings"
    ]
  }
]

tracks/java/config.json
[
  {
    "slug": "bracket-push",
    "difficulty": 5,
    "topics": []
  }
]

tracks/lua/config.json
[
  {
    "slug": "bracket-push",
    "difficulty": 5,
    "topics": [
      "stacks",
      "strings",
      "algorithms",
      "control-flow (if-else statements)",
      "control-flow (loops)"
    ]
  }
]

tracks/objective-c/config.json
[
  {
    "difficulty": 5,
    "slug": "bracket-push",
    "topics": [
      "Strings",
      "Conditionals",
      "Looping"
    ]
  }
]

tracks/ocaml/config.json
[
  {
    "slug": "bracket-push",
    "difficulty": 4,
    "topics": [
      "Stacks"
    ]
  }
]

tracks/rust/config.json
[
  {
    "slug": "bracket-push",
    "difficulty": 4,
    "topics": [
      "From trait",
      "stack or recursion"
    ]
  }
]

tracks/swift/config.json
[
  {
    "difficulty": 7,
    "slug": "bracket-push",
    "topics": [
      "Parsing",
      "Strings"
    ]
  }
]

[lpalma]

In that case, I'll include Stack in the list of topics and increase its difficulty to 5. I agree it shouldn't go any higher than that.

[petertseng]

OK.

The only other exercise I can think of that would get Stack in its topic list at the same time would be forth.

[petertseng]

It's true that once one realizes one can use a stack, it is easy. So the hard part is not writing the implementation. It is figuring out how to tackle the problem at all.

Because of this, I would actually rate higher, maybe 4 or 5.

If it helps to see how other tracks rated it:

for i in tracks/*/config.json; do echo $i; jq 'if any(.exercises[]; .difficulty != 1) then .exercises | map(select(.slug == "bracket-push")) else [] end' < $i; done

tracks/ceylon/config.json
[
  {
    "slug": "bracket-push",
    "difficulty": 6,
    "topics": [
      "Parsing",
      "Stacks",
      "Strings"
    ]
  }
]

tracks/csharp/config.json
[
  {
    "slug": "bracket-push",
    "difficulty": 5,
    "topics": [
      "Parsing",
      "Strings"
    ]
  }
]

tracks/elixir/config.json
[
  {
    "slug": "bracket-push",
    "difficulty": 3,
    "topics": []
  }
]

tracks/fsharp/config.json
[
  {
    "slug": "bracket-push",
    "difficulty": 7,
    "topics": [
      "Parsing",
      "Strings"
    ]
  }
]

tracks/java/config.json
[
  {
    "slug": "bracket-push",
    "difficulty": 5,
    "topics": []
  }
]

tracks/lua/config.json
[
  {
    "slug": "bracket-push",
    "difficulty": 5,
    "topics": [
      "stacks",
      "strings",
      "algorithms",
      "control-flow (if-else statements)",
      "control-flow (loops)"
    ]
  }
]

tracks/objective-c/config.json
[
  {
    "difficulty": 5,
    "slug": "bracket-push",
    "topics": [
      "Strings",
      "Conditionals",
      "Looping"
    ]
  }
]

tracks/ocaml/config.json
[
  {
    "slug": "bracket-push",
    "difficulty": 4,
    "topics": [
      "Stacks"
    ]
  }
]

tracks/rust/config.json
[
  {
    "slug": "bracket-push",
    "difficulty": 4,
    "topics": [
      "From trait",
      "stack or recursion"
    ]
  }
]

tracks/swift/config.json
[
  {
    "difficulty": 7,
    "slug": "bracket-push",
    "topics": [
      "Parsing",
      "Strings"
    ]
  }
]

[petertseng]

I would just call the module Brackets. the Push is too much of an implementation detail and I don't even think it should go in the name: exercism/problem-specifications#693

I would maybe call the function arePaired so that can read like Brackets.arePaired, and this makes sense since it handles multiple brackets not just one pair.

[petertseng]

same q as #511 (comment) - same across all exercises, or allow to be different?

[petertseng]

same q as #511 (comment) - how should we put the version in here?

[lpalma]

thanks for the feedback @petertseng, they have been addressed.

[petertseng]

I think this will be ready if we make the Stack version uniform.