From 89e7e9b636d2364ef766b97c533dc3f685a794d6 Mon Sep 17 00:00:00 2001
From: John MacFarlane <jgm@berkeley.edu>
Date: Sat, 1 Oct 2022 12:46:30 -0700
Subject: [PATCH] Makefile: add moduledeps target.

    make moduledeps ROOTNODE=T.P.Parsing
---
 Makefile              |  5 +++++
 tools/depthfirst.gvpr | 18 ++++++++++++++++++
 2 files changed, 23 insertions(+)
 create mode 100644 tools/depthfirst.gvpr

diff --git a/Makefile b/Makefile
index 9388c5d6f..4d58079bc 100644
--- a/Makefile
+++ b/Makefile
@@ -180,6 +180,11 @@ modules.dot: $(SOURCEFILES)
 modules.pdf: modules.dot
 	gvpr -f tools/cliptree.gvpr -a '"$(ROOTNODE)"' $< | dot -Tpdf > $@
 
+# make moduledeps ROOTNODE=T.P.Parsing
+moduledeps: modules.dot  ## Print dependencies of a module ROOTNODE
+	gvpr -f tools/depthfirst.gvpr -a '"$(ROOTNODE)"' modules.dot
+.PHONY: moduledeps
+
 clean: ## clean up
 	cabal clean
 .PHONY: clean
diff --git a/tools/depthfirst.gvpr b/tools/depthfirst.gvpr
new file mode 100644
index 000000000..5539be22e
--- /dev/null
+++ b/tools/depthfirst.gvpr
@@ -0,0 +1,18 @@
+BEGIN {
+  int i, indent;
+  int seen[string];
+  void prInd (int cnt) {
+  for (i = 0; i < cnt; i++) printf (" "); }
+}
+BEG_G {
+  $tvtype = TV_prepostfwd; $tvroot = node($,ARGV[0]);
+} N{
+  if (seen[$.name]) {
+    indent--;
+    if (indent == 0) exit(0);
+  } else {
+    prInd(indent); print ($.name);
+    seen[$.name] = 1;
+    indent++;
+  }
+}