The recommended way to install the components of the mac platform is using ghcup to install ghc and cabal-install. haskell.org
ghcup is an installer for the general purpose language Haskell
Open a terminal and execute the following command to install
curl https://get-ghcup.haskell.org -sSf | sh
ENTER -> type
ENTER to accept the prompts in terminal.
From ghcup README
# prepare your environment . "$HOME/.ghcup/env"
You should now be able to execute
ghcup into your terminal.
To make sure that the environment variables are setup on new terminal windows.
echo '. $HOME/.ghcup/env' >> "$HOME/.bashrc"
echo '. $HOME/.ghcup/env' >> "$HOME/.zshrc"
Follow the instruction on haskellstack.org to install stack.
If you have homebrew…
brew install haskell-stack