相关疑难解决方法(0)

我写了一个简单的模块叫做Test:

module Test (main) where

main =
  putStrLn "Hello"

但是,当我尝试通过以下命令行编译它时:

ghc Test.hs -o my-program

我收到以下错误:

[1 of 1] Compiling Test             ( Test.hs, Test.o )

<no location info>: error:
    output was redirected with -o, but no output will be generated because there is no Main module.

我在app文件夹中有两个文件

app/
|-- Main.hs
|-- SomeFunc2.hs

该SomeFunc2.hs仅仅是打印不同的字符串

module SomeFunc2 where

import Lib

main :: IO ()
main = putStrLn "someFunc2"

当我package.yaml像这样定义多个可执行文件时

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

  somefunc2-exe:
    main:                SomeFunc2.hs
    source-dirs:         app
    ghc-options:
    - -threaded
    - -rtsopts
    - -with-rtsopts=-N
    dependencies:
    - multiexes

我有错误：

? stack build
Building all executables for `multiexes' once. After a successful build of all of them, only specified executables will …