Haskell collatz conjecture

.github/workflows/haskell.yml

@@ -1,10 +1,11 @@
+---
 #
 # .github/workflows/haskell.yml
 #
----
 name: Haskell Workflow
 on:  # yamllint disable-line rule:truthy
   pull_request:
+
 jobs:
   stage1:
     name: Change Check
@@ -31,7 +32,7 @@ jobs:
           # Check if the files are present in the changed file list (added, modified, deleted) then output to stdout.
           HAS_DIFF=false
           printf "=== Which Haskell files changed? ===\n"
-          if printf "%s\n" "${GIT_DIFF}" | grep -E '^(.*[.](hs|cabal)|.*/stack[.]yaml[.].*|.github/workflows/haskell.yml)$'; then
+          if printf "%s\n" "${GIT_DIFF}" | grep -E '^(haskell/.*[.](hs|cabal)|haskell/.*/stack[.]yaml[.].*|.github/workflows/haskell.yml)$'; then
             HAS_DIFF=true
           fi
           printf "\n"
@@ -94,6 +95,6 @@ jobs:
           ./for_each hlint src --report
       - name: Testing with coverage
         id: haskell-test-coverage
-        run: |
+        run: |-
           cd ./haskell
           ./for_each stack test --coverage

haskell/README.md

@@ -19,3 +19,8 @@
 - [space-age](./space-age/README.md)
 - [bob](./bob/README.md)
 - [triangle](./triangle/README.md)
+- [collatz-conjecture](./collatz-conjecture/README.md)
+- [hamming](./hamming/README.md)
+- [protein-translation](./protein-translation/README.md)
+- [robot-simulator](./robot-simulator/README.md)
+- [yacht](./yacht/README.md)

haskell/collatz-conjecture/.exercism/config.json

@@ -0,0 +1,30 @@
+{
+  "authors": [],
+  "contributors": [
+    "guygastineau",
+    "iHiD",
+    "navossoc",
+    "petertseng",
+    "ppartarr",
+    "sshine",
+    "tejasbubane"
+  ],
+  "files": {
+    "solution": [
+      "src/CollatzConjecture.hs",
+      "package.yaml"
+    ],
+    "test": [
+      "test/Tests.hs"
+    ],
+    "example": [
+      ".meta/examples/success-standard/src/CollatzConjecture.hs"
+    ],
+    "invalidator": [
+      "stack.yaml"
+    ]
+  },
+  "blurb": "Calculate the number of steps to reach 1 using the Collatz conjecture.",
+  "source": "An unsolved problem in mathematics named after mathematician Lothar Collatz",
+  "source_url": "https://en.wikipedia.org/wiki/3x_%2B_1_problem"
+}

haskell/collatz-conjecture/.exercism/metadata.json

@@ -0,0 +1 @@
+{"track":"haskell","exercise":"collatz-conjecture","id":"17d391e3c4b6400cba19f838366e68b9","url":"https://exercism.org/tracks/haskell/exercises/collatz-conjecture","handle":"vpayno","is_requester":true,"auto_approve":false}

haskell/collatz-conjecture/HELP.md

@@ -0,0 +1,86 @@
+# Help
+
+## Running the tests
+
+To run the test suite, execute the following command:
+
+```bash
+stack test
+```
+
+#### If you get an error message like this...
+
+```
+No .cabal file found in directory
+```
+
+or
+
+```
+RedownloadInvalidResponse Request {
+...
+}
+ "/home/username/.stack/build-plan/lts-xx.yy.yaml" (Response {responseStatus = Status {statusCode = 404, statusMessage = "Not Found"},
+```
+
+You are probably running an old stack version and need
+to upgrade it. Try running:
+
+```bash
+stack upgrade
+```
+
+Or see other options for upgrading at [Stack documentation](https://docs.haskellstack.org/en/stable/install_and_upgrade/#upgrade).
+
+#### Otherwise, if you get an error message like this...
+
+```
+No compiler found, expected minor version match with...
+Try running "stack setup" to install the correct GHC...
+```
+
+Just do as it says and it will download and install
+the correct compiler version:
+
+```bash
+stack setup
+```
+
+If you want to play with your solution in GHCi, just run the command:
+
+```bash
+stack ghci
+```
+
+## Submitting your solution
+
+You can submit your solution using the `exercism submit src/CollatzConjecture.hs package.yaml` command.
+This command will upload your solution to the Exercism website and print the solution page's URL.
+
+It's possible to submit an incomplete solution which allows you to:
+
+- See how others have completed the exercise
+- Request help from a mentor
+
+## Need to get help?
+
+If you'd like help solving the exercise, check the following pages:
+
+- The [Haskell track's documentation](https://exercism.org/docs/tracks/haskell)
+- [Exercism's programming category on the forum](https://forum.exercism.org/c/programming/5)
+- The [Frequently Asked Questions](https://exercism.org/docs/using/faqs)
+
+Should those resources not suffice, you could submit your (incomplete) solution to request mentoring.
+
+## Getting Started
+
+Please refer to the [installation](https://exercism.io/tracks/haskell/installation)
+and [learning](https://exercism.io/tracks/haskell/learning) help pages.
+
+## Feedback, Issues, Pull Requests
+
+The [exercism/haskell](https://github.com/exercism/haskell) repository on
+GitHub is the home for all of the Haskell exercises.
+
+If you have feedback about an exercise, or want to help implementing a new
+one, head over there and create an issue.  We'll do our best to help you!

haskell/collatz-conjecture/README.md

@@ -0,0 +1,53 @@
+# Collatz Conjecture
+
+Welcome to Collatz Conjecture on Exercism's Haskell Track.
+If you need help running the tests or submitting your code, check out `HELP.md`.
+
+## Instructions
+
+The Collatz Conjecture or 3x+1 problem can be summarized as follows:
+
+Take any positive integer n. If n is even, divide n by 2 to get n / 2. If n is
+odd, multiply n by 3 and add 1 to get 3n + 1. Repeat the process indefinitely.
+The conjecture states that no matter which number you start with, you will
+always reach 1 eventually.
+
+Given a number n, return the number of steps required to reach 1.
+
+## Examples
+
+Starting with n = 12, the steps would be as follows:
+
+0. 12
+1. 6
+2. 3
+3. 10
+4. 5
+5. 16
+6. 8
+7. 4
+8. 2
+9. 1
+
+Resulting in 9 steps. So for input n = 12, the return value would be 9.
+
+## Source
+
+### Contributed to by
+
+- @guygastineau
+- @iHiD
+- @navossoc
+- @petertseng
+- @ppartarr
+- @sshine
+- @tejasbubane
+
+### Based on
+
+An unsolved problem in mathematics named after mathematician Lothar Collatz - https://en.wikipedia.org/wiki/3x_%2B_1_problem
+
+### My Solution
+
+- [my solution](./src/CollatzConjecture.hs)
+- [run-tests](./run-tests-haskell.txt)

haskell/collatz-conjecture/collatz-conjecture.cabal

@@ -0,0 +1,34 @@
+cabal-version: 1.12
+
+-- This file has been generated from package.yaml by hpack version 0.35.1.
+--
+-- see: https://github.com/sol/hpack
+
+name:           collatz-conjecture
+version:        1.2.1.4
+build-type:     Simple
+
+library
+  exposed-modules:
+      CollatzConjecture
+  other-modules:
+      Paths_collatz_conjecture
+  hs-source-dirs:
+      src
+  ghc-options: -Wall
+  build-depends:
+      base
+  default-language: Haskell2010
+
+test-suite test
+  type: exitcode-stdio-1.0
+  main-is: Tests.hs
+  other-modules:
+      Paths_collatz_conjecture
+  hs-source-dirs:
+      test
+  build-depends:
+      base
+    , collatz-conjecture
+    , hspec
+  default-language: Haskell2010

haskell/collatz-conjecture/package.yaml

@@ -0,0 +1,21 @@
+name: collatz-conjecture
+version: 1.2.1.4
+
+dependencies:
+  - base
+
+library:
+  exposed-modules: CollatzConjecture
+  source-dirs: src
+  ghc-options: -Wall
+  # dependencies:
+  # - foo       # List here the packages you
+  # - bar       # want to use in your solution.
+
+tests:
+  test:
+    main: Tests.hs
+    source-dirs: test
+    dependencies:
+      - collatz-conjecture
+      - hspec