Installation instructions for Agda 2.6.1.1 on Mac OS.
=====================================================

0. [Optional] Install command line tools for XCode if you haven't done
   so before.

   Go to https://developer.apple.com/download/more/ and download the
   DMG file for command line tools for XCode 12.3. You will be asked
   to use your Apple credentials to sign in.  Once you have downloaded
   the DMG file, double click to install as usual.

1. Install Home Brew.
   Open a terminal and enter the following:

   /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"

2. Install Emacs.
   In the terminal, enter the following:

   brew install --cask --no-quarantine emacs

   Note: now you should be able to find Emacs in your /Application
   folder.  If double clicking the icon does not open it because
   "Apple cannot check it for malicious software", right-click on the
   icon and click open. After this, Emacs should be opened alright.

3. Install Agda.
   In the terminal, enter the following:

   brew install agda

   Now if you enter "agda --version", you should see something like
   "Agda version 2.6.1.2".

4. Set up Agda.
   In the terminal, enter the following:

   agda-mode setup

5. Create an empty file called "nat.agda" and open it in Emacs.
   Paste the following Agda code to the file.

   data Nat : Set where
     Z : Nat
     S : Nat -> Nat

   Notice that there is no color for the above Agda code after you
   pasted it.  Now type Ctrl-C, followed by Ctrl-L in Emacs. This will
   color the above Agda code. If you see the colored code,
   congratulation, you have managed to set up Agda!  If not, don't
   worry. Come to ask us for help.