How to import and bind System.Directory using "The Haskell Tool Stack"

Question

This question already has an answer here: question from:https://stackoverflow.com/questions/65892923/how-to-import-and-bind-system-directory-using-the-haskell-tool-stack

Answer 1

In package.yaml, add directory to the dependencies: field

dependencies:
  - directory

The relevant part of the error message is this one:

Perhaps you need to add `directory' to the build-depends in your .cabal file.

And in your case, the .cabal file is generated from package.yaml. This is done using the hpack tool which is used by default in stack.

Many people don't use hpack (they remove package.yaml and edit the .cabal file directly), and this is why a lot of the documentation you may find won't apply if you do use hpack.