From 37606d41d3dcc574dd6b755de4849fe899c01af2 Mon Sep 17 00:00:00 2001
From: Rich Hickey <richhickey@gmail.com>
Date: Wed, 1 Apr 2009 12:39:39 +0000
Subject: [PATCH] added get-method

---
 src/clj/clojure/core.clj          | 5 +++++
 src/jvm/clojure/lang/MultiFn.java | 7 ++++++-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/src/clj/clojure/core.clj b/src/clj/clojure/core.clj
index f44fcb71a5..934dbe89fa 100644
--- a/src/clj/clojure/core.clj
+++ b/src/clj/clojure/core.clj
@@ -1085,6 +1085,11 @@
   "Given a multimethod, returns a map of dispatch values -> dispatch fns"
   [#^clojure.lang.MultiFn multifn] (.getMethodTable multifn))
 
+(defn get-method
+  "Given a multimethod and a dispatch value, returns the dispatch fn
+  that would apply to that value, or nil if none apply and no default"
+  [#^clojure.lang.MultiFn multifn dispatch-val] (.getMethod multifn dispatch-val))
+
 (defn prefers
   "Given a multimethod, returns a map of preferred value -> set of other values"
   [#^clojure.lang.MultiFn multifn] (.getPreferTable multifn))
diff --git a/src/jvm/clojure/lang/MultiFn.java b/src/jvm/clojure/lang/MultiFn.java
index d7b089ce7f..1efa84b6a4 100644
--- a/src/jvm/clojure/lang/MultiFn.java
+++ b/src/jvm/clojure/lang/MultiFn.java
@@ -93,7 +93,7 @@ private IPersistentMap resetCache() throws Exception{
 	return methodCache;
 }
 
-synchronized private IFn getFn(Object dispatchVal) throws Exception{
+synchronized public IFn getMethod(Object dispatchVal) throws Exception{
 	if(cachedHierarchy != hierarchy.deref())
 		resetCache();
 	IFn targetFn = (IFn) methodCache.valAt(dispatchVal);
@@ -103,6 +103,11 @@ synchronized private IFn getFn(Object dispatchVal) throws Exception{
 	if(targetFn != null)
 		return targetFn;
 	targetFn = (IFn) getMethodTable().valAt(defaultDispatchVal);
+	return targetFn;
+}
+
+private IFn getFn(Object dispatchVal) throws Exception{
+	IFn targetFn = getMethod(dispatchVal);
 	if(targetFn == null)
 		throw new IllegalArgumentException(String.format("No method for dispatch value: %s", dispatchVal));
 	return targetFn;