How to reload the project after dependencies is added?

Question

During the development, I've added a library to package.yaml and the GHCi is already started.

For example, I've added the bytestring library:

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

Because I use it in a file that is called Families.hs and it contains the following code:

{-# LANGUAGE  TypeFamilies, OverloadedStrings #-}

module Families where

import Data.Word (Word8)
import qualified Data.ByteString as BS

When I try to load the file, it complains:

:l ./src/Families.hs
[1 of 1] Compiling Families         ( src/Families.hs, interpreted )

src/Families.hs:6:1: error:
    Could not load module ‘Data.ByteString’
    It is a member of the hidden package ‘bytestring-0.10.8.2’.
    You can run ‘:set -package bytestring’ to expose it.
    (Note: this unloads all the modules in the current scope.)
    Use -v to see a list of the files searched for.
  |
6 | import qualified Data.ByteString as BS
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Failed, no modules loaded.

The question is, how to reload the whole project into the GHCi and allow usage of bytestring library.

UPDATE
I also tried with :reload and got

:reload
[1 of 1] Compiling Families         ( src/Families.hs, interpreted )

src/Families.hs:6:1: error:
    Could not load module ‘Data.ByteString’
    It is a member of the hidden package ‘bytestring-0.10.8.2’.
    You can run ‘:set -package bytestring’ to expose it.
    (Note: this unloads all the modules in the current scope.)
    Use -v to see a list of the files searched for.
  |
6 | import qualified Data.ByteString as BS
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Failed, no modules loaded.

I'm not sure you can do that, then. For fast prototyping, I usually do something like this: `stack build --fast --filewatch`. — Sibi, Feb 22 '19 at 11:06
Yes, I am using intero. I followed this instruction http://spacemacs.org/layers/+lang/haskell/README.html. — softshipper, Feb 22 '19 at 13:49

score 0 · Answer 1 · answered Feb 22 '19 at 15:28

I see you are using Spacemacs along with intero. In this case you may restart whole intero process by typing M-x intero-restart RET, or M-RET i r which will reload all stack dependencies.

Another way to do this is to put your cursor on the error import and type C-c C-r to let the intero automatically fix the issue.

How to reload the project after dependencies is added?

1 Answers1