✅ haskell: pangram

haskell/pangram/HELP.md

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+# 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/Pangram.hs` 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 support channel on gitter](https://gitter.im/exercism/support)
+- 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!
+{{ with .Spec.Credits }}

haskell/pangram/README.md

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+# Pangram
+
+Welcome to Pangram on Exercism's Haskell Track.
+If you need help running the tests or submitting your code, check out `HELP.md`.
+
+## Instructions
+
+Determine if a sentence is a pangram. A pangram (Greek: παν γράμμα, pan gramma,
+"every letter") is a sentence using every letter of the alphabet at least once.
+The best known English pangram is:
+> The quick brown fox jumps over the lazy dog.
+
+The alphabet used consists of ASCII letters `a` to `z`, inclusive, and is case
+insensitive. Input will not contain non-ASCII symbols.
+
+## Source
+
+### Created by
+
+- @lpalma
+
+### Contributed to by
+
+- @chiroptical
+- @iHiD
+- @navossoc
+- @petertseng
+- @ppartarr
+- @rbasso
+- @rsslldnphy
+- @Sir4ur0n
+- @sshine
+- @tejasbubane
+
+### Based on
+
+Wikipedia - https://en.wikipedia.org/wiki/Pangram

haskell/pangram/examples/success-standard/package.yaml

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+name: pangram
+
+dependencies:
+  - base
+
+library:
+  exposed-modules: Pangram
+  source-dirs: src
+
+tests:
+  test:
+    main: Tests.hs
+    source-dirs: test
+    dependencies:
+      - pangram
+      - hspec

haskell/pangram/examples/success-text/package.yaml

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+name: pangram
+
+dependencies:
+  - base
+  - text
+
+library:
+  exposed-modules: Pangram
+  source-dirs: src
+
+tests:
+  test:
+    main: Tests.hs
+    source-dirs: test
+    dependencies:
+      - pangram
+      - hspec

haskell/pangram/examples/success-text/src/Pangram.hs

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+module Pangram (isPangram) where
+
+import           Data.Text (Text)
+import qualified Data.Text as T
+
+isPangram :: Text -> Bool
+isPangram s = all (`member` T.toLower s) ['a'..'z']
+  where member = T.any . (==)

haskell/pangram/package.yaml

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+name: pangram
+version: 2.0.0.12
+
+dependencies:
+  - base
+
+library:
+  exposed-modules: Pangram
+  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:
+      - pangram
+      - hspec

haskell/pangram/src/Pangram.hs

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+module Pangram (isPangram) where
+
+import Data.Char
+
+isPangram :: String -> Bool
+isPangram text = all hasLetter ['a' .. 'z']
+  where hasLetter l = any (== l) (map toLower text)

haskell/pangram/stack.yaml

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+resolver: lts-16.21

haskell/pangram/test/Tests.hs

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+{-# LANGUAGE RecordWildCards #-}
+{-# LANGUAGE OverloadedStrings #-}
+
+import Data.Foldable     (for_)
+import Data.String       (fromString)
+import Test.Hspec        (Spec, describe, it, shouldBe)
+import Test.Hspec.Runner (configFastFail, defaultConfig, hspecWith)
+
+import Pangram (isPangram)
+
+main :: IO ()
+main = hspecWith defaultConfig {configFastFail = True} specs
+
+specs :: Spec
+specs = describe "isPangram" $ for_ cases test
+  where
+    test Case{..} = it description $ isPangram (fromString input) `shouldBe` expected
+
+data Case = Case { description :: String
+                 , input       :: String
+                 , expected    :: Bool
+                 }
+
+cases :: [Case]
+cases = [ Case { description = "with empty sentence"
+               , input       = ""
+               , expected    = False
+               }
+        , Case { description = "with perfect lower case"
+               , input       = "abcdefghijklmnopqrstuvwxyz"
+               , expected    = True
+               }
+        , Case { description = "with only lower case"
+               , input       = "the quick brown fox jumps over the lazy dog"
+               , expected    = True
+               }
+        , Case { description = "with missing character 'x'"
+               , input       = "a quick movement of the enemy will jeopardize five gunboats"
+               , expected    = False
+               }
+        , Case { description = "with missing character 'h'"
+               , input       = "five boxing wizards jump quickly at it"
+               , expected    = False
+               }
+        , Case { description = "with underscores"
+               , input       = "the_quick_brown_fox_jumps_over_the_lazy_dog"
+               , expected    = True
+               }
+        , Case { description = "with numbers"
+               , input       = "the 1 quick brown fox jumps over the 2 lazy dogs"
+               , expected    = True
+               }
+        , Case { description = "with missing letters replaced by numbers"
+               , input       = "7h3 qu1ck brown fox jumps ov3r 7h3 lazy dog"
+               , expected    = False
+               }
+        , Case { description = "with mixed case and punctuation"
+               , input       = "\"Five quacking Zephyrs jolt my wax bed.\""
+               , expected    = True
+               }
+        , Case { description = "with mixed case"
+               , input       = "the quick brown fox jumps over with lazy FX"
+               , expected    = False
+               }
+        , Case { description = "with missing character and non-ascii letters"
+               , input       = "abcdefghijklmnopqrstuvwxyÃ"
+               , expected    = False
+               }
+        , Case { description = "with additional non-ascii letters"
+               , input       = "abcdefghijklmnopqrstuvwxyzÃ"
+               , expected    = True
+               }
+
+        {-
+        -- The following test can be enabled for String-based solutions:
+        , Case { description = "with termination as soon as all letters have occurred"
+               , input       = "abcdefghijklmnopqrstuvwxyz" ++ [undefined]
+               , expected    = True
+               }
+        -- -}
+        ]
+
+-- 73e37723b154f0c741d227c43af09d23dc7e5e44