Change how constant maps are emitted. This returns to the 'optimization' that exists in the JVM version. A tiny bit slower, maybe, but decrease in memory usage.

Author: dmiller

Clojure/Clojure/CljCompiler/Ast/MapExpr.cs

@@ -77,32 +77,17 @@ public static Expr Parse(ParserContext pcon, IPersistentMap form)
 
             if (form is IObj iobjForm && iobjForm.meta() != null)
                 return Compiler.OptionallyGenerateMetaInit(pcon, form, ret);
-            //else if (constant)
-            //{
-            // This 'optimzation' works, mostly, unless you have nested map values.
-            // The nested map values do not participate in the constants map, so you end up with the code to create the keys.
-            // Result: huge duplication of keyword creation.  3X increase in init time to the REPL.
-            //    //IPersistentMap m = PersistentHashMap.EMPTY;
-            //    //for (int i = 0; i < keyvals.length(); i += 2)
-            //    //    m = m.assoc(((LiteralExpr)keyvals.nth(i)).Val, ((LiteralExpr)keyvals.nth(i + 1)).Val);
-            //    //return new ConstantExpr(m);
-            //    return ret;
-            //}
             else if (keysConstant)
             {
                 // TBD: Add more detail to exception thrown below.
                 if (!allConstantKeysUnique)
                     throw new ArgumentException("Duplicate constant keys in map");
                 if (valsConstant)
                 {
-                    // This 'optimzation' works, mostly, unless you have nested map values.
-                    // The nested map values do not participate in the constants map, so you end up with the code to create the keys.
-                    // Result: huge duplication of keyword creation.  3X increase in init time to the REPL.
-                    //IPersistentMap m = PersistentArrayMap.EMPTY;
-                    //for (int i = 0; i < keyvals.length(); i += 2)
-                    //    m = m.assoc(((LiteralExpr)keyvals.nth(i)).Val, ((LiteralExpr)keyvals.nth(i + 1)).Val);
-                    //return new ConstantExpr(m);
-                    return ret;
+                    IPersistentMap m = PersistentArrayMap.EMPTY;
+                    for (int i = 0; i < keyvals.length(); i += 2)
+                        m = m.assoc(((LiteralExpr)keyvals.nth(i)).Val, ((LiteralExpr)keyvals.nth(i + 1)).Val);
+                    return new ConstantExpr(m);
                 }
                 else
                     return ret;