diff -r 545b68843709 -r b310bc57f55f lib/Tools/ghc_stack
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lib/Tools/ghc_stack	Wed Oct 17 21:38:07 2018 +0200
@@ -0,0 +1,7 @@
+#!/usr/bin/env bash
+#
+# Author: Makarius
+#
+# DESCRIPTION: invoke Haskell Tool Stack within the Isabelle environment
+
+isabelle_stack "$@"