From 56a0d874c76fccfd1cbd1ede2c464446e889d302 Mon Sep 17 00:00:00 2001
From: John MacFarlane <jgm@berkeley.edu>
Date: Fri, 30 Apr 2021 08:35:52 -0700
Subject: [PATCH] Add instructions for installing pandoc-types before compiling
 filter.

---
 doc/filters.md | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/doc/filters.md b/doc/filters.md
index 46db09f78..004a83b7d 100644
--- a/doc/filters.md
+++ b/doc/filters.md
@@ -394,6 +394,8 @@ automatically assign it `Just` the target format or `Nothing`.
 
 We compile our script:
 
+    # first, make sure pandoc-types is installed:
+    cabal install --lib pandoc-types --package-env .
     ghc --make handleRuby
 
 Then run it: