計算機科学のブログ

name:                http-lesson
version:             0.1.0.0
github:              "githubuser/http-lesson"
license:             BSD-3-Clause
author:              "Author name here"
maintainer:          "example@example.com"
copyright:           "2025 Author name here"

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/http-lesson#readme>

dependencies:
- base >= 4.7 && < 5
- bytestring
- http-conduit

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:
  http-lesson-exe:
    main:                Main.hs
    source-dirs:         app
    ghc-options:
    - -threaded
    - -rtsopts
    - -with-rtsopts=-N
    dependencies:
    - http-lesson

tests:
  http-lesson-test:
    main:                Spec.hs
    source-dirs:         test
    ghc-options:
    - -threaded
    - -rtsopts
    - -with-rtsopts=-N
    dependencies:
    - http-lesson

{-# LANGUAGE OverloadedStrings #-}
module Main (main) where

import qualified Data.ByteString as B
import qualified Data.ByteString.Char8 as BC
import qualified Data.ByteString.Lazy as L
import qualified Data.ByteString.Lazy.Char8 as LC
import Network.HTTP.Simple
main :: IO ()
main = print "hi"

% stack run  
http-lesson> build (lib + exe) with ghc-9.8.4
Preprocessing library for http-lesson-0.1.0.0..
Building library for http-lesson-0.1.0.0..
Preprocessing executable 'http-lesson-exe' for http-lesson-0.1.0.0..
Building executable 'http-lesson-exe' for http-lesson-0.1.0.0..
[1 of 2] Compiling Main

/Users/.../http-lesson/app/Main.hs:4:1: warning: [GHC-66111] [-Wunused-imports]
    The qualified import of ‘Data.ByteString’ is redundant
      except perhaps to import instances from ‘Data.ByteString’
    To import instances alone, use: import Data.ByteString()
  |
4 | import qualified Data.ByteString as B
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

/Users/.../http-lesson/app/Main.hs:5:1: warning: [GHC-66111] [-Wunused-imports]
    The qualified import of ‘Data.ByteString.Char8’ is redundant
      except perhaps to import instances from ‘Data.ByteString.Char8’
    To import instances alone, use: import Data.ByteString.Char8()
  |
5 | import qualified Data.ByteString.Char8 as BC
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

/Users/.../http-lesson/app/Main.hs:6:1: warning: [GHC-66111] [-Wunused-imports]
    The qualified import of ‘Data.ByteString.Lazy’ is redundant
      except perhaps to import instances from ‘Data.ByteString.Lazy’
    To import instances alone, use: import Data.ByteString.Lazy()
  |
6 | import qualified Data.ByteString.Lazy as L
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

/Users/.../http-lesson/app/Main.hs:7:1: warning: [GHC-66111] [-Wunused-imports]
    The qualified import of ‘Data.ByteString.Lazy.Char8’ is redundant
      except perhaps to import instances from ‘Data.ByteString.Lazy.Char8’
    To import instances alone, use: import Data.ByteString.Lazy.Char8()
  |
7 | import qualified Data.ByteString.Lazy.Char8 as LC
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

/Users/.../http-lesson/app/Main.hs:8:1: warning: [GHC-66111] [-Wunused-imports]
    The import of ‘Network.HTTP.Simple’ is redundant
      except perhaps to import instances from ‘Network.HTTP.Simple’
    To import instances alone, use: import Network.HTTP.Simple()
  |
8 | import Network.HTTP.Simple
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^

/Users/.../http-lesson/app/Main.hs:10:8: warning: [GHC-18042] [-Wtype-defaults]
    • Defaulting the type variable ‘a0’ to type ‘String’ in the following constraints
        (Show a0) arising from a use of ‘print’ at app/Main.hs:10:8-12
        (Data.String.IsString a0)
          arising from the literal ‘"hi"’ at app/Main.hs:10:14-17
    • In the expression: print "hi"
      In an equation for ‘main’: main = print "hi"
   |
10 | main = print "hi"
   |        ^^^^^
[3 of 3] Linking .stack-work/dist/aarch64-osx/ghc-9.8.4/build/http-lesson-exe/http-lesson-exe
ld: warning: -U option is redundant when using -undefined dynamic_lookup
http-lesson> copy/register
Installing library in /Users/.../http-lesson/.stack-work/install/aarch64-osx/e2dcdb9c07548bf6dae5f9b6f2750a6303aa3357cf62332e90692b200e5825d0/9.8.4/lib/aarch64-osx-ghc-9.8.4/http-lesson-0.1.0.0-GvOmP0p2gw480pL83GZ8q7
Installing executable http-lesson-exe in /Users/.../http-lesson/.stack-work/install/aarch64-osx/e2dcdb9c07548bf6dae5f9b6f2750a6303aa3357cf62332e90692b200e5825d0/9.8.4/bin
Registering library for http-lesson-0.1.0.0..
"hi"
%