From c99d87b033ae585d32ede62f3089f7675b6bc71b Mon Sep 17 00:00:00 2001
From: Alan Malloy <alan@malloys.org>
Date: Wed, 26 Oct 2011 12:22:50 -0700
Subject: [PATCH 2/2] Preserve &form metadata on macroexpanded forms

---
 src/jvm/clojure/lang/Compiler.java |   24 +++++++++++++++++++++++-
 1 files changed, 23 insertions(+), 1 deletions(-)

diff --git a/src/jvm/clojure/lang/Compiler.java b/src/jvm/clojure/lang/Compiler.java
index a4485d7..3b19623 100644
--- a/src/jvm/clojure/lang/Compiler.java
+++ b/src/jvm/clojure/lang/Compiler.java
@@ -6346,9 +6346,31 @@ public static Object macroexpand1(Object x) {
 		Var v = isMacro(op);
 		if(v != null)
 			{
+				IPersistentMap preMeta = null;
+				if (form instanceof IMeta)
+					{
+						preMeta = ((IMeta)form).meta();
+					}
 				try
 					{
-						return v.applyTo(RT.cons(form,RT.cons(LOCAL_ENV.get(),form.next())));
+						Object expansion = v.applyTo(RT.cons(form,RT.cons(LOCAL_ENV.get(),form.next())));
+						if (preMeta == null || !(expansion instanceof IObj))
+							{
+								return expansion;
+							}
+						IObj ret = (IObj)expansion;
+						IPersistentMap mergedMeta = ret.meta();
+						if (mergedMeta == null)
+							{
+								mergedMeta = PersistentArrayMap.EMPTY;
+							}
+						ISeq pairs = preMeta.without(RT.LINE_KEY).without(RT.FILE_KEY).seq();
+						while (pairs != null)
+							{
+								mergedMeta = (IPersistentMap)mergedMeta.cons(pairs.first());
+								pairs = pairs.next();
+							}
+						return ret.withMeta(mergedMeta);
 					}
 				catch(ArityException e)
 					{
-- 
1.7.4.1