[lazy] added closed-over local tail clearing, for once-only fns, used in delay

1 files changed, 21 insertions, 0 deletions

diff --git a/src/jvm/clojure/lang/Compiler.java b/src/jvm/clojure/lang/Compiler.java
index 0b57c389..50921f7f 100644
--- a/src/jvm/clojure/lang/Compiler.java
+++ b/src/jvm/clojure/lang/Compiler.java
@@ -2817,6 +2817,7 @@ static public class FnExpr implements Expr{
 	int line;
 	PersistentVector constants;
 	int constantsID;
+    boolean onceOnly = false;
 
 	public final IPersistentCollection methods(){
 		return methods;
@@ -2898,6 +2899,7 @@ static public class FnExpr implements Expr{
 	static Expr parse(C context, ISeq form, String name) throws Exception{
 		FnExpr fn = new FnExpr(tagOf(form));
 		FnMethod enclosingMethod = (FnMethod) METHOD.get();
+        fn.onceOnly = RT.booleanCast(RT.get(RT.meta(form.first()), Keyword.intern(null, "once")));
 		//fn.thisName = name;
 		String basename = enclosingMethod != null ?
 		                  (enclosingMethod.fn.name + "$")
@@ -3211,6 +3213,21 @@ static public class FnExpr implements Expr{
             }
     }
 
+    void emitClearCloses(GeneratorAdapter gen){
+        int a = 1;
+        for(ISeq s = RT.keys(closes); s != null; s = s.rest(), ++a)
+			{
+			LocalBinding lb = (LocalBinding) s.first();
+			Class primc = lb.getPrimitiveType();
+			if(primc == null)
+				{
+                gen.loadThis();
+                gen.visitInsn(Opcodes.ACONST_NULL);
+                gen.putField(fntype, lb.name, OBJECT_TYPE);
+				}
+			}
+    }
+
 	synchronized Class getCompiledClass(){
 		if(compiledClass == null)
 			try
@@ -3537,6 +3554,10 @@ public static class FnMethod{
                     }
 				}
 			}
+        if(fn.onceOnly)
+            {
+            fn.emitClearCloses(gen);
+            }
 	}
 }