Haskell - コードの整理とプロジェクトのビルド - stackを使ってプロジェクトをビルトする - コードを記述する
入門Haskellプログラミング (Will Kurt(著)、株式会社クイープ(監修、翻訳)、翔泳社)の UNIT6(コードの整理とプロジェクトのビルド)、LESSON 35(stackを使ってプロジェクトをビルトする)、35.3(コードを記述する)、Q35-3の解答を求めてみる。
軽量マークアップ言語
palindrome-checker/package.yaml
name: palindrome-checker
version: 0.1.0.0
github: "githubuser/palindrome-checker"
license: BSD-3-Clause
author: "kamimura"
maintainer: "example@example.com"
copyright: "2025 kamimura"
extra-source-files:
- README.md
- CHANGELOG.md
# Metadata used when publishing your package
# synopsis: Short description of your package
# category: Web
# To avoid duplicated efforts in documentation and dealing with the
# complications of embedding Haddock markup inside cabal files, it is
# common to point users to the README.md file.
description: Please see the README on GitHub at <https://github.com/githubuser/palindrome-checker#readme>
dependencies:
- base >= 4.7 && < 5
- text
ghc-options:
- -Wall
- -Wcompat
- -Widentities
- -Wincomplete-record-updates
- -Wincomplete-uni-patterns
- -Wmissing-export-lists
- -Wmissing-home-modules
- -Wpartial-fields
- -Wredundant-constraints
library:
source-dirs: src
executables:
palindrome-checker-exe:
main: Main.hs
source-dirs: app
ghc-options:
- -threaded
- -rtsopts
- -with-rtsopts=-N
dependencies:
- palindrome-checker
tests:
palindrome-checker-test:
main: Spec.hs
source-dirs: test
ghc-options:
- -threaded
- -rtsopts
- -with-rtsopts=-N
dependencies:
- palindrome-checker
軽量マークアップ言語
palindrome-checker/palindrome-checker.cabal
cabal-version: 2.2
-- This file has been generated from package.yaml by hpack version 0.37.0.
--
-- see: https://github.com/sol/hpack
name: palindrome-checker
version: 0.1.0.0
description: Please see the README on GitHub at <https://github.com/githubuser/palindrome-checker#readme>
homepage: https://github.com/githubuser/palindrome-checker#readme
bug-reports: https://github.com/githubuser/palindrome-checker/issues
author: kamimura
maintainer: example@example.com
copyright: 2025 kamimura
license: BSD-3-Clause
license-file: LICENSE
build-type: Simple
extra-source-files:
README.md
CHANGELOG.md
source-repository head
type: git
location: https://github.com/githubuser/palindrome-checker
library
exposed-modules:
Lib
Palindrome
other-modules:
Paths_palindrome_checker
autogen-modules:
Paths_palindrome_checker
hs-source-dirs:
src
ghc-options: -Wall -Wcompat -Widentities -Wincomplete-record-updates -Wincomplete-uni-patterns -Wmissing-export-lists -Wmissing-home-modules -Wpartial-fields -Wredundant-constraints
build-depends:
base >=4.7 && <5
, text
default-language: Haskell2010
executable palindrome-checker-exe
main-is: Main.hs
other-modules:
Paths_palindrome_checker
autogen-modules:
Paths_palindrome_checker
hs-source-dirs:
app
ghc-options: -Wall -Wcompat -Widentities -Wincomplete-record-updates -Wincomplete-uni-patterns -Wmissing-export-lists -Wmissing-home-modules -Wpartial-fields -Wredundant-constraints -threaded -rtsopts -with-rtsopts=-N
build-depends:
base >=4.7 && <5
, palindrome-checker
, text
default-language: Haskell2010
test-suite palindrome-checker-test
type: exitcode-stdio-1.0
main-is: Spec.hs
other-modules:
Paths_palindrome_checker
autogen-modules:
Paths_palindrome_checker
hs-source-dirs:
test
ghc-options: -Wall -Wcompat -Widentities -Wincomplete-record-updates -Wincomplete-uni-patterns -Wmissing-export-lists -Wmissing-home-modules -Wpartial-fields -Wredundant-constraints -threaded -rtsopts -with-rtsopts=-N
build-depends:
base >=4.7 && <5
, palindrome-checker
, text
default-language: Haskell2010
コード
palindrome-checker/app/Main.hs
{-# LANGUAGE OverloadedStrings #-}
module Main (main) where
import Palindrome(isPalindrome)
import qualified Data.Text.IO as TIO
main :: IO ()
main = do
TIO.putStrLn "Enter a word and I'll let you know if it's a palindrome!"
text <- TIO.getLine
let response = if isPalindrome text
then "it is!"
else "it's not!"
TIO.putStrLn response
コード
palindrome-checker/src/Palindrome.hs
{-# LANGUAGE OverloadedStrings #-}
module Palindrome(isPalindrome) where
import qualified Data.Text as T
import Data.Char (toLower,isSpace,isPunctuation)
stripWhiteSpace :: T.Text -> T.Text
stripWhiteSpace = T.filter (not . isSpace)
stripPunctuation :: T.Text -> T.Text
stripPunctuation = T.filter (not . isPunctuation)
preProcess :: T.Text -> T.Text
preProcess = stripWhiteSpace . stripPunctuation . T.toLower
isPalindrome :: T.Text -> Bool
isPalindrome text = cleanText == T.reverse cleanText
where cleanText = preProcess text
入出力結果(Terminal, Zsh)
% stack run
palindrome-checker-0.1.0.0: unregistering (local file changes: app/Main.hs)
palindrome-checker> build (lib + exe) with ghc-9.8.4
Preprocessing library for palindrome-checker-0.1.0.0..
Building library for palindrome-checker-0.1.0.0..
Preprocessing executable 'palindrome-checker-exe' for palindrome-checker-0.1.0.0..
Building executable 'palindrome-checker-exe' for palindrome-checker-0.1.0.0..
[1 of 2] Compiling Main [Source file changed]
[3 of 3] Linking .stack-work/dist/aarch64-osx/ghc-9.8.4/build/palindrome-checker-exe/palindrome-checker-exe [Objects changed]
ld: warning: -U option is redundant when using -undefined dynamic_lookup
palindrome-checker> copy/register
Installing library in /.../palindrome-checker/.stack-work/install/aarch64-osx/e7436b3217cf53d6b9beeebd2bdc5dd8dcab6f8595b8bde259631442ce745f25/9.8.4/lib/aarch64-osx-ghc-9.8.4/palindrome-checker-0.1.0.0-AsDJJAXtgGvCwcL0FmK5ox
Installing executable palindrome-checker-exe in /.../palindrome-checker/.stack-work/install/aarch64-osx/e7436b3217cf53d6b9beeebd2bdc5dd8dcab6f8595b8bde259631442ce745f25/9.8.4/bin
Registering library for palindrome-checker-0.1.0.0..
Enter a word and I'll let you know if it's a palindrome!
Racer
it's not!
% stack run
Enter a word and I'll let you know if it's a palindrome!
Race car
it is!
%