JS: rewrite more natives with templates, get rid of runtime aliases in minification mode

classlib/src/main/java/org/teavm/classlib/impl/ServiceLoaderJSSupport.java

@@ -16,10 +16,10 @@
 package org.teavm.classlib.impl;
 
 import java.io.IOException;
-import java.util.Collection;
 import org.teavm.backend.javascript.codegen.SourceWriter;
 import org.teavm.backend.javascript.spi.Generator;
 import org.teavm.backend.javascript.spi.GeneratorContext;
+import org.teavm.backend.javascript.templating.JavaScriptTemplateFactory;
 import org.teavm.model.MethodDescriptor;
 import org.teavm.model.MethodReference;
 
@@ -28,39 +28,31 @@ public class ServiceLoaderJSSupport implements Generator {
 
     @Override
     public void generate(GeneratorContext context, SourceWriter writer, MethodReference methodRef) throws IOException {
-        ServiceLoaderInformation information = context.getService(ServiceLoaderInformation.class);
+        var templateFactory = new JavaScriptTemplateFactory(context.getClassLoader(), context.getClassSource());
-        writer.append("if (!").appendClass("java.util.ServiceLoader").append(".$$services$$) {").indent()
+        var template = templateFactory.createFromResource("org/teavm/classlib/java/util/ServiceLoader.js");
-                .softNewLine();
+        var information = context.getService(ServiceLoaderInformation.class);
-        writer.appendClass("java.util.ServiceLoader").append(".$$services$$ = true;").softNewLine();
+        var fragment = template.builder("loadServices")
-        for (String serviceType : information.serviceTypes()) {
+                .withContext(context)
-            writer.appendClass(serviceType).append(".$$serviceList$$ = [");
+                .withFragment("fillServices", (w, precedence) -> {
-            Collection<? extends String> implementations = information.serviceImplementations(serviceType);
+                    for (var serviceType : information.serviceTypes()) {
-            boolean first = true;
+                        writer.appendClass(serviceType).append(".$$serviceList$$ = [");
-            for (String implName : implementations) {
+                        var implementations = information.serviceImplementations(serviceType);
-                if (context.getClassSource().getClassNames().contains(implName)) {
+                        boolean first = true;
-                    if (!first) {
+                        for (var implName : implementations) {
-                        writer.append(", ");
+                            if (context.getClassSource().getClassNames().contains(implName)) {
+                                if (!first) {
+                                    writer.append(",").ws();
+                                }
+                                first = false;
+                                writer.append("[").appendClass(implName).append(",").ws()
+                                        .appendMethodBody(new MethodReference(implName, INIT_METHOD))
+                                        .append("]");
+                            }
+                        }
+                        writer.append("];").softNewLine();
                     }
-                    first = false;
+                })
-                    writer.append("[").appendClass(implName).append(", ").appendMethodBody(
+                .build();
-                            new MethodReference(implName, INIT_METHOD))
+        fragment.write(writer, 0);
-                            .append("]");
-                }
-            }
-            writer.append("];").softNewLine();
-        }
-        writer.outdent().append("}").softNewLine();
-        String param = context.getParameterName(1);
-        writer.append("var cls = " + param + ";").softNewLine();
-        writer.append("if (!cls.$$serviceList$$) {").indent().softNewLine();
-        writer.append("return $rt_createArray($rt_objcls(), 0);").softNewLine();
-        writer.outdent().append("}").softNewLine();
-        writer.append("var result = $rt_createArray($rt_objcls(), cls.$$serviceList$$.length);").softNewLine();
-        writer.append("for (var i = 0; i < result.data.length; ++i) {").indent().softNewLine();
-        writer.append("var serviceDesc = cls.$$serviceList$$[i];").softNewLine();
-        writer.append("result.data[i] = new serviceDesc[0]();").softNewLine();
-        writer.append("serviceDesc[1](result.data[i]);").softNewLine();
-        writer.outdent().append("}").softNewLine();
-        writer.append("return result;").softNewLine();
     }
 }

classlib/src/main/java/org/teavm/classlib/impl/string/JSStringInjector.java

@@ -122,7 +122,7 @@ public class JSStringInjector implements Injector, Function<ProviderContext, Inj
         var writer = context.getWriter();
         context.writeExpr(context.getArgument(0));
         writer.append(".").appendField(NATIVE_FIELD).ws().append("=").ws();
-        writer.append("$rt_charArrayToString").append("(");
+        writer.appendFunction("$rt_charArrayToString").append("(");
         context.writeExpr(context.getArgument(1));
         writer.append(".data,").ws();
         context.writeExpr(context.getArgument(2));
@@ -135,7 +135,7 @@ public class JSStringInjector implements Injector, Function<ProviderContext, Inj
         var writer = context.getWriter();
         context.writeExpr(context.getArgument(0));
         writer.append(".").appendField(NATIVE_FIELD).ws().append("=").ws();
-        writer.append("$rt_fullArrayToString").append("(");
+        writer.appendFunction("$rt_fullArrayToString").append("(");
         context.writeExpr(context.getArgument(1));
         writer.append(".data)");
     }
@@ -156,7 +156,7 @@ public class JSStringInjector implements Injector, Function<ProviderContext, Inj
 
     private void copyCharsToArray(InjectorContext context) throws IOException {
         var writer = context.getWriter();
-        writer.append("$rt_stringToCharArray").append("(");
+        writer.appendFunction("$rt_stringToCharArray").append("(");
         context.writeExpr(context.getArgument(0));
         writer.append(".").appendField(NATIVE_FIELD);
         writer.append(",").ws();
@@ -183,7 +183,7 @@ public class JSStringInjector implements Injector, Function<ProviderContext, Inj
 
     private void fastCharArray(InjectorContext context) throws IOException {
         var writer = context.getWriter();
-        writer.append("$rt_fastStringToCharArray").append("(");
+        writer.appendFunction("$rt_fastStringToCharArray").append("(");
         context.writeExpr(context.getArgument(0));
         writer.append(".").appendField(NATIVE_FIELD);
         writer.append(")");

classlib/src/main/java/org/teavm/classlib/java/lang/ClassGenerator.java

@@ -55,7 +55,7 @@ public class ClassGenerator implements Generator, Injector, DependencyPlugin {
     public void generate(InjectorContext context, MethodReference methodRef) throws IOException {
         switch (methodRef.getName()) {
             case "newEmptyInstance":
-                context.getWriter().append("new (");
+                context.getWriter().append("new").ws().append("(");
                 context.writeExpr(context.getArgument(0), Precedence.MEMBER_ACCESS);
                 context.getWriter().append('.').appendField(platformClassField);
                 context.getWriter().append(")");

classlib/src/main/java/org/teavm/classlib/java/lang/ClassLoaderNativeGenerator.java

@@ -75,7 +75,7 @@ public class ClassLoaderNativeGenerator implements Injector {
                     dataChars[i] = (char) dataBytes[i];
                 }
                 RenderingUtil.writeString(writer, resource);
-                writer.ws().append(':').ws();
+                writer.append(':').ws();
                 RenderingUtil.writeString(writer, new String(dataChars));
             }
         }

classlib/src/main/java/org/teavm/classlib/java/lang/DoubleGenerator.java

@@ -31,7 +31,8 @@ public class DoubleGenerator implements Injector {
             context.getWriter().append(')');
             return;
         }
-        context.getWriter().append("$rt_").append(methodRef.getName()).append("(");
+        var functionName = "$rt_" + methodRef.getName();
+        context.getWriter().appendFunction(functionName).append("(");
         context.writeExpr(context.getArgument(0));
         context.getWriter().append(")");
     }

classlib/src/main/java/org/teavm/classlib/java/lang/IntegerNativeGenerator.java

@@ -25,26 +25,23 @@ public class IntegerNativeGenerator implements Injector {
     public void generate(InjectorContext context, MethodReference methodRef) throws IOException {
         switch (methodRef.getName()) {
             case "divideUnsigned":
-                context.getWriter().append("$rt_udiv(");
+                generateRuntimeCall(context, "$rt_udiv");
-                context.writeExpr(context.getArgument(0));
-                context.getWriter().append(",").ws();
-                context.writeExpr(context.getArgument(1));
-                context.getWriter().append(")");
                 break;
             case "remainderUnsigned":
-                context.getWriter().append("$rt_umod(");
+                generateRuntimeCall(context, "$rt_umod");
-                context.writeExpr(context.getArgument(0));
-                context.getWriter().append(",").ws();
-                context.writeExpr(context.getArgument(1));
-                context.getWriter().append(")");
                 break;
             case "compareUnsigned":
-                context.getWriter().append("$rt_ucmp(");
+                generateRuntimeCall(context, "$rt_ucmp");
-                context.writeExpr(context.getArgument(0));
-                context.getWriter().append(",").ws();
-                context.writeExpr(context.getArgument(1));
-                context.getWriter().append(")");
                 break;
         }
     }
+
+
+    private void generateRuntimeCall(InjectorContext context, String name) throws IOException {
+        context.getWriter().appendFunction(name).append("(");
+        context.writeExpr(context.getArgument(0));
+        context.getWriter().append(",").ws();
+        context.writeExpr(context.getArgument(1));
+        context.getWriter().append(")");
+    }
 }

classlib/src/main/java/org/teavm/classlib/java/lang/MathNativeGenerator.java

@@ -31,12 +31,12 @@ public class MathNativeGenerator implements Generator {
         if (name.equals("signum")) {
             name = "sign";
         }
-        function(context, writer, "Math." + name, methodRef.parameterCount());
+        function(context, writer, name, methodRef.parameterCount());
     }
 
     private void function(GeneratorContext context, SourceWriter writer, String name, int paramCount)
             throws IOException {
-        writer.append("return ").append(name).append("(");
+        writer.append("return ").append("$rt_globals.Math").append(".").append(name).append("(");
         for (int i = 0; i < paramCount; ++i) {
             if (i > 0) {
                 writer.append(",").ws();

classlib/src/main/java/org/teavm/classlib/java/lang/reflect/ArrayDependencyPlugin.java

@@ -0,0 +1,111 @@
+/*
+ *  Copyright 2023 Alexey Andreev.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+package org.teavm.classlib.java.lang.reflect;
+
+import java.util.HashSet;
+import java.util.Set;
+import org.teavm.dependency.DependencyAgent;
+import org.teavm.dependency.DependencyPlugin;
+import org.teavm.dependency.MethodDependency;
+import org.teavm.model.MethodReference;
+import org.teavm.model.ValueType;
+
+public class ArrayDependencyPlugin implements DependencyPlugin {
+    private static final String[] primitives = { "Byte", "Short", "Char", "Int", "Long", "Float", "Double",
+            "Boolean" };
+    private static final String[] primitiveWrappers = { "Byte", "Short", "Character", "Integer", "Long",
+            "Float", "Double", "Boolean" };
+    private static final ValueType[] primitiveTypes = { ValueType.BYTE, ValueType.SHORT, ValueType.CHARACTER,
+            ValueType.INTEGER, ValueType.LONG, ValueType.FLOAT, ValueType.DOUBLE, ValueType.BOOLEAN };
+
+    private Set<MethodReference> reachedMethods = new HashSet<>();
+
+    @Override
+    public void methodReached(DependencyAgent agent, MethodDependency method) {
+        if (!reachedMethods.add(method.getReference())) {
+            return;
+        }
+        switch (method.getReference().getName()) {
+            case "getLength":
+                reachGetLength(agent, method);
+                break;
+            case "newInstance":
+                method.getVariable(1).getClassValueNode().addConsumer(t -> {
+                    String arrayTypeName;
+                    if (t.getName().startsWith("[")) {
+                        arrayTypeName = t.getName();
+                    } else if (t.getName().startsWith("~")) {
+                        arrayTypeName = t.getName().substring(1);
+                    } else {
+                        arrayTypeName = ValueType.object(t.getName()).toString();
+                    }
+                    if (!arrayTypeName.startsWith("[[[")) {
+                        method.getResult().propagate(agent.getType("[" + arrayTypeName));
+                    }
+                });
+                break;
+            case "getImpl":
+                reachGet(agent, method);
+                break;
+            case "setImpl":
+                reachSet(agent, method);
+                break;
+        }
+    }
+
+    private void reachGetLength(DependencyAgent agent, MethodDependency method) {
+        method.getVariable(1).addConsumer(type -> {
+            if (!type.getName().startsWith("[")) {
+                MethodReference cons = new MethodReference(IllegalArgumentException.class, "<init>", void.class);
+                agent.linkMethod(cons).use();
+            }
+        });
+    }
+    private void reachGet(DependencyAgent agent, MethodDependency method) {
+        method.getVariable(1).getArrayItem().connect(method.getResult());
+        method.getVariable(1).addConsumer(type -> {
+            if (type.getName().startsWith("[")) {
+                String typeName = type.getName().substring(1);
+                for (int i = 0; i < primitiveTypes.length; ++i) {
+                    if (primitiveTypes[i].toString().equals(typeName)) {
+                        String wrapper = "java.lang." + primitiveWrappers[i];
+                        MethodReference methodRef = new MethodReference(wrapper, "valueOf",
+                                primitiveTypes[i], ValueType.object(wrapper));
+                        agent.linkMethod(methodRef).use();
+                        method.getResult().propagate(agent.getType("java.lang." + primitiveWrappers[i]));
+                    }
+                }
+            }
+        });
+    }
+
+    private void reachSet(DependencyAgent agent, MethodDependency method) {
+        method.getVariable(3).connect(method.getVariable(1).getArrayItem());
+        method.getVariable(1).addConsumer(type -> {
+            if (type.getName().startsWith("[")) {
+                String typeName = type.getName().substring(1);
+                for (int i = 0; i < primitiveTypes.length; ++i) {
+                    if (primitiveTypes[i].toString().equals(typeName)) {
+                        String wrapper = "java.lang." + primitiveWrappers[i];
+                        MethodReference methodRef = new MethodReference(wrapper,
+                                primitives[i].toLowerCase() + "Value", primitiveTypes[i]);
+                        agent.linkMethod(methodRef).use();
+                    }
+                }
+            }
+        });
+    }
+}

classlib/src/main/java/org/teavm/classlib/java/lang/reflect/ArrayNativeGenerator.java

@@ -16,190 +16,22 @@
 package org.teavm.classlib.java.lang.reflect;
 
 import java.io.IOException;
-import java.util.HashSet;
-import java.util.Set;
 import org.teavm.backend.javascript.codegen.SourceWriter;
 import org.teavm.backend.javascript.spi.Generator;
 import org.teavm.backend.javascript.spi.GeneratorContext;
-import org.teavm.dependency.DependencyAgent;
+import org.teavm.backend.javascript.templating.JavaScriptTemplate;
-import org.teavm.dependency.DependencyPlugin;
+import org.teavm.backend.javascript.templating.JavaScriptTemplateFactory;
-import org.teavm.dependency.MethodDependency;
-import org.teavm.model.ClassReader;
 import org.teavm.model.MethodReference;
-import org.teavm.model.ValueType;
 
-public class ArrayNativeGenerator implements Generator, DependencyPlugin {
+public class ArrayNativeGenerator implements Generator {
-    private static final String[] primitives = { "Byte", "Short", "Char", "Int", "Long", "Float", "Double",
+    private JavaScriptTemplate template;
-            "Boolean" };
-    private static final String[] primitiveWrappers = { "Byte", "Short", "Character", "Integer", "Long",
-            "Float", "Double", "Boolean" };
-    private static final ValueType[] primitiveTypes = { ValueType.BYTE, ValueType.SHORT, ValueType.CHARACTER,
-            ValueType.INTEGER, ValueType.LONG, ValueType.FLOAT, ValueType.DOUBLE, ValueType.BOOLEAN };
 
-    private Set<MethodReference> reachedMethods = new HashSet<>();
+    public ArrayNativeGenerator(JavaScriptTemplateFactory templateFactory) throws IOException {
-
+        template = templateFactory.createFromResource("org/teavm/classlib/java/lang/reflect/Array.js");
-    @Override
-    public void methodReached(DependencyAgent agent, MethodDependency method) {
-        if (!reachedMethods.add(method.getReference())) {
-            return;
-        }
-        switch (method.getReference().getName()) {
-            case "getLength":
-                reachGetLength(agent, method);
-                break;
-            case "newInstance":
-                method.getVariable(1).getClassValueNode().addConsumer(t -> {
-                    String arrayTypeName;
-                    if (t.getName().startsWith("[")) {
-                        arrayTypeName = t.getName();
-                    } else if (t.getName().startsWith("~")) {
-                        arrayTypeName = t.getName().substring(1);
-                    } else {
-                        arrayTypeName = ValueType.object(t.getName()).toString();
-                    }
-                    if (!arrayTypeName.startsWith("[[[")) {
-                        method.getResult().propagate(agent.getType("[" + arrayTypeName));
-                    }
-                });
-                break;
-            case "getImpl":
-                reachGet(agent, method);
-                break;
-            case "setImpl":
-                reachSet(agent, method);
-                break;
-        }
     }
 
     @Override
     public void generate(GeneratorContext context, SourceWriter writer, MethodReference methodRef) throws IOException {
-        switch (methodRef.getName()) {
+        template.builder(methodRef.getName()).withContext(context).build().write(writer, 0);
-            case "getLength":
-                generateGetLength(context, writer);
-                break;
-            case "newInstanceImpl":
-                generateNewInstance(context, writer);
-                break;
-            case "getImpl":
-                generateGet(context, writer);
-                break;
-            case "setImpl":
-                generateSet(context, writer);
-                break;
-        }
-    }
-
-    private void generateGetLength(GeneratorContext context, SourceWriter writer) throws IOException {
-        String array = context.getParameterName(1);
-        writer.append("if (" + array + " === null || " + array + ".constructor.$meta.item === undefined) {")
-                .softNewLine().indent();
-        MethodReference cons = new MethodReference("java.lang.IllegalArgumentException", "<init>", ValueType.VOID);
-        writer.append("$rt_throw(").appendInit(cons).append("());").softNewLine();
-        writer.outdent().append("}").softNewLine();
-        writer.append("return " + array + ".data.length;").softNewLine();
-    }
-
-    private void reachGetLength(DependencyAgent agent, MethodDependency method) {
-        method.getVariable(1).addConsumer(type -> {
-            if (!type.getName().startsWith("[")) {
-                MethodReference cons = new MethodReference(IllegalArgumentException.class, "<init>", void.class);
-                agent.linkMethod(cons).use();
-            }
-        });
-    }
-
-    private void generateNewInstance(GeneratorContext context, SourceWriter writer) throws IOException {
-        String type = context.getParameterName(1);
-        String length = context.getParameterName(2);
-        writer.append("if (").append(type).append(".$meta.primitive) {").softNewLine().indent();
-        for (String primitive : primitives) {
-            writer.append("if (" + type + " == $rt_" + primitive.toLowerCase() + "cls) {").indent().softNewLine();
-            writer.append("return $rt_create" + primitive + "Array(" + length + ");").softNewLine();
-            writer.outdent().append("}").softNewLine();
-        }
-        writer.outdent().append("} else {").indent().softNewLine();
-        writer.append("return $rt_createArray(" + type + ", " + length + ")").softNewLine();
-        writer.outdent().append("}").softNewLine();
-    }
-
-    private void generateGet(GeneratorContext context, SourceWriter writer) throws IOException {
-        String array = context.getParameterName(1);
-        writer.append("var item = " + array + ".data[" + context.getParameterName(2) + "];").softNewLine();
-        writer.append("var type = " + array + ".constructor.$meta.item;").softNewLine();
-        for (int i = 0; i < primitives.length; ++i) {
-            String wrapper = "java.lang." + primitiveWrappers[i];
-            MethodReference methodRef = new MethodReference(wrapper, "valueOf",
-                    primitiveTypes[i], ValueType.object(wrapper));
-            ClassReader cls = context.getClassSource().get(methodRef.getClassName());
-            if (cls == null || cls.getMethod(methodRef.getDescriptor()) == null) {
-                continue;
-            }
-            writer.append("if (type === $rt_" + primitives[i].toLowerCase() + "cls) {").indent().softNewLine();
-            writer.append("return ").appendMethodBody(methodRef).append("(item);").softNewLine();
-            writer.outdent().append("} else ");
-        }
-        writer.append("{").indent().softNewLine();
-        writer.append("return item;").softNewLine();
-        writer.outdent().append("}").softNewLine();
-    }
-
-    private void generateSet(GeneratorContext context, SourceWriter writer) throws IOException {
-        String array = context.getParameterName(1);
-        String item = context.getParameterName(3);
-        writer.append("var type = " + array + ".constructor.$meta.item;").softNewLine();
-        boolean first = true;
-        for (int i = 0; i < primitives.length; ++i) {
-            String wrapper = "java.lang." + primitiveWrappers[i];
-            MethodReference methodRef = new MethodReference(wrapper, primitives[i].toLowerCase() + "Value",
-                    primitiveTypes[i]);
-            ClassReader cls = context.getClassSource().get(methodRef.getClassName());
-            if (cls == null || cls.getMethod(methodRef.getDescriptor()) == null) {
-                continue;
-            }
-            if (!first) {
-                writer.append(" else ");
-            }
-            first = false;
-            writer.append("if (type === $rt_" + primitives[i].toLowerCase() + "cls) {").indent().softNewLine();
-            writer.append(item + " = ").appendMethodBody(methodRef).append("(" + item + ");").softNewLine();
-            writer.outdent().append("}");
-        }
-        writer.softNewLine();
-        writer.append(array + ".data[" + context.getParameterName(2) + "] = " + item + ";").softNewLine();
-    }
-
-    private void reachGet(DependencyAgent agent, MethodDependency method) {
-        method.getVariable(1).getArrayItem().connect(method.getResult());
-        method.getVariable(1).addConsumer(type -> {
-            if (type.getName().startsWith("[")) {
-                String typeName = type.getName().substring(1);
-                for (int i = 0; i < primitiveTypes.length; ++i) {
-                    if (primitiveTypes[i].toString().equals(typeName)) {
-                        String wrapper = "java.lang." + primitiveWrappers[i];
-                        MethodReference methodRef = new MethodReference(wrapper, "valueOf",
-                                primitiveTypes[i], ValueType.object(wrapper));
-                        agent.linkMethod(methodRef).use();
-                        method.getResult().propagate(agent.getType("java.lang." + primitiveWrappers[i]));
-                    }
-                }
-            }
-        });
-    }
-
-    private void reachSet(DependencyAgent agent, MethodDependency method) {
-        method.getVariable(3).connect(method.getVariable(1).getArrayItem());
-        method.getVariable(1).addConsumer(type -> {
-            if (type.getName().startsWith("[")) {
-                String typeName = type.getName().substring(1);
-                for (int i = 0; i < primitiveTypes.length; ++i) {
-                    if (primitiveTypes[i].toString().equals(typeName)) {
-                        String wrapper = "java.lang." + primitiveWrappers[i];
-                        MethodReference methodRef = new MethodReference(wrapper,
-                                primitives[i].toLowerCase() + "Value", primitiveTypes[i]);
-                        agent.linkMethod(methodRef).use();
-                    }
-                }
-            }
-        });
     }
 }

classlib/src/main/java/org/teavm/classlib/java/lang/reflect/TArray.java

@@ -33,7 +33,7 @@ import org.teavm.runtime.RuntimeObject;
 
 public final class TArray extends TObject {
     @GeneratedBy(ArrayNativeGenerator.class)
-    @PluggableDependency(ArrayNativeGenerator.class)
+    @PluggableDependency(ArrayDependencyPlugin.class)
     @DelegateTo("getLengthLowLevel")
     @NoSideEffects
     public static native int getLength(TObject array) throws TIllegalArgumentException;
@@ -48,7 +48,7 @@ public final class TArray extends TObject {
         return array.size;
     }
 
-    @PluggableDependency(ArrayNativeGenerator.class)
+    @PluggableDependency(ArrayDependencyPlugin.class)
     public static TObject newInstance(Class<?> componentType, int length) throws TNegativeArraySizeException {
         if (componentType == null) {
             throw new TNullPointerException();
@@ -89,12 +89,12 @@ public final class TArray extends TObject {
     }
 
     @GeneratedBy(ArrayNativeGenerator.class)
-    @PluggableDependency(ArrayNativeGenerator.class)
+    @PluggableDependency(ArrayDependencyPlugin.class)
     @NoSideEffects
     private static native TObject getImpl(TObject array, int index);
 
     @GeneratedBy(ArrayNativeGenerator.class)
-    @PluggableDependency(ArrayNativeGenerator.class)
+    @PluggableDependency(ArrayDependencyPlugin.class)
     @NoSideEffects
     private static native void setImpl(TObject array, int index, TObject value);
 }

classlib/src/main/resources/org/teavm/classlib/java/lang/ref/ReferenceQueue.js

@@ -0,0 +1,33 @@
+/*
+ *  Copyright 2023 Alexey Andreev.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+function init() {
+    this[teavm_javaField("java.lang.ref.ReferenceQueue", "inner")] = [];
+    if (teavm_javaMethodExists("java.lang.ref.ReferenceQueue", "reportNext(Ljava/lang/ref/Reference;)Z")) {
+        this[teavm_javaField("java.lang.ref.ReferenceQueue", "registry")] =
+            new (teavm_globals.FinalizationRegistry)(ref => {
+                if (!teavm_javaMethod("java.lang.ref.ReferenceQueue",
+                        "reportNext(Ljava/lang/ref/Reference;)Z")(this, ref)) {
+                    this[teavm_javaField("java.lang.ref.ReferenceQueue", "inner")].push(ref);
+                }
+            });
+    }
+}
+
+function poll() {
+    var value = this[teavm_javaField("java.lang.ref.ReferenceQueue", "inner")];
+    return typeof value !== 'undefined' ? value : null;
+}

classlib/src/main/resources/org/teavm/classlib/java/lang/ref/WeakReference.js

@@ -0,0 +1,41 @@
+/*
+ *  Copyright 2023 Alexey Andreev.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+function init(target, queue) {
+    let supported = typeof teavm_globals.WeakRef !== 'undefined';
+    let value = supported ? new teavm_globals.WeakRef(target) : target;
+    this[teavm_javaField("java.lang.ref.WeakReference", "value")] = value;
+    if (queue !== null && supported) {
+        let registry = queue[teavm_javaField("java.lang.ref.ReferenceQueue", "registry")];
+        if (registry !== null) {
+            registry.register(target, this);
+        }
+    }
+}
+function get() {
+    let value = this[teavm_javaField("java.lang.ref.WeakReference", "value")];
+    if (typeof teavm_globals.WeakRef !== 'undefined') {
+        if (value === null) {
+            return null;
+        }
+        let result = value.deref();
+        return typeof result !== 'undefined' ? result : null;
+    }
+    return value;
+}
+function clear() {
+    this[teavm_javaField("java.lang.ref.WeakReference", "value")] = null;
+}

classlib/src/main/resources/org/teavm/classlib/java/lang/reflect/Array.js

@@ -0,0 +1,86 @@
+/*
+ *  Copyright 2023 Alexey Andreev.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+function getLength(array) {
+    if (array === null || array.constructor.$meta.item === 'undefined') {
+        $rt_throw(teavm_javaConstructor("java.lang.IllegalArgumentException", "()V")());
+    }
+    return array.data.length;
+}
+
+function newInstanceImpl(type, length) {
+    if (type.$meta.primitive) {
+        switch (type) {
+            case $rt_booleanArrayCls: return $rt_createBooleanArray(length);
+            case $rt_byteArrayCls: return $rt_createByteArray(length);
+            case $rt_shortArrayCls: return $rt_createShortArray(length);
+            case $rt_charArrayCls: return $rt_createCharArray(length);
+            case $rt_intArrayCls: return $rt_createIntArray(length);
+            case $rt_longArrayCls: return $rt_createLongArray(length);
+            case $rt_floatArrayCls: return $rt_createFloatArray(length);
+            case $rt_doubleArrayCls: return $rt_createDoubleArray(length);
+        }
+    }
+    return $rt_createArray(type, length);
+}
+
+function getImpl(array, index) {
+    var item = array.data[index];
+    var type = array.constructor.$meta.item;
+    if (teavm_javaMethodExists("java.lang.Boolean", "valueOf(Z)Ljava/lang/Boolean;") && type === $rt_booleancls) {
+        return teavm_javaMethod("java.lang.Boolean", "valueOf(Z)Ljava/lang/Boolean;")(item);
+    } else if (teavm_javaMethodExists("java.lang.Byte", "valueOf(B)Ljava/lang/Byte;") && type === $rt_bytecls) {
+        return teavm_javaMethod("java.lang.Byte", "valueOf(B)Ljava/lang/Byte;")(item);
+    } else if (teavm_javaMethodExists("java.lang.Short", "valueOf(S)Ljava/lang/Short;") && type === $rt_shortcls) {
+        return teavm_javaMethod("java.lang.Short", "valueOf(S)Ljava/lang/Short;")(item);
+    } else if (teavm_javaMethodExists("java.lang.Character", "valueOf(C)Ljava/lang/Character;")
+            && type === $rt_charcls) {
+        return teavm_javaMethod("java.lang.Character", "valueOf(C)Ljava/lang/Character;")(item);
+    } else if (teavm_javaMethodExists("java.lang.Integer", "valueOf(I)Ljava/lang/Integer;") && type === $rt_intcls) {
+        return teavm_javaMethod("java.lang.Integer", "valueOf(I)Ljava/lang/Integer;")(item);
+    } else if (teavm_javaMethodExists("java.lang.Long", "valueOf(J)Ljava/lang/Long;") && type === $rt_longcls) {
+        return teavm_javaMethod("java.lang.Long", "valueOf(J)Ljava/lang/Long;")(item);
+    } else if (teavm_javaMethodExists("java.lang.Float", "valueOf(F)Ljava/lang/Float;") && type === $rt_floatcls) {
+        return teavm_javaMethod("java.lang.Float", "valueOf(F)Ljava/lang/Float;")(item);
+    } else if (teavm_javaMethodExists("java.lang.Double", "valueOf(D)Ljava/lang/Double;") && type === $rt_doublecls) {
+        return teavm_javaMethod("java.lang.Double", "valueOf(D)Ljava/lang/Double;")(item);
+    } else {
+        return item;
+    }
+}
+
+function setImpl(array, index, value) {
+    var type = array.constructor.$meta.item;
+    if (teavm_javaMethodExists("java.lang.Boolean", "booleanValue()Z") && type === $rt_booleancls) {
+        array.data[index] = teavm_javaMethod("java.lang.Boolean", "booleanValue()Z")(value);
+    } else if (teavm_javaMethodExists("java.lang.Byte", "byteValue()B") && type === $rt_booleancls) {
+        array.data[index] = teavm_javaMethod("java.lang.Byte", "byteValue()B")(value);
+    } else if (teavm_javaMethodExists("java.lang.Short", "shortValue()S") && type === $rt_shortcls) {
+        array.data[index] = teavm_javaMethod("java.lang.Short", "shortValue()S")(value);
+    } else if (teavm_javaMethodExists("java.lang.Character", "charValue()C") && type === $rt_charcls) {
+        array.data[index] = teavm_javaMethod("java.lang.Character", "charValue()C")(value);
+    } else if (teavm_javaMethodExists("java.lang.Integer", "intValue()I") && type === $rt_intcls) {
+        array.data[index] = teavm_javaMethod("java.lang.Integer", "intValue()I")(value);
+    } else if (teavm_javaMethodExists("java.lang.Long", "longValue()J") && type === $rt_longcls) {
+        array.data[index] = teavm_javaMethod("java.lang.Long", "longValue()J")(value);
+    } else if (teavm_javaMethodExists("java.lang.Float", "floatValue()F") && type === $rt_floatcls) {
+        array.data[index] = teavm_javaMethod("java.lang.Float", "floatValue()F")(value);
+    } else if (teavm_javaMethodExists("java.lang.Double", "doubleValue()D") && type === $rt_floatcls) {
+        array.data[index] = teavm_javaMethod("java.lang.Double", "doubleValue()D")(value);
+    } else {
+        array.data[index] = value;
+    }
+}

classlib/src/main/resources/org/teavm/classlib/java/util/ServiceLoader.js

@@ -0,0 +1,38 @@
+/*
+ *  Copyright 2023 Alexey Andreev.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+function loadServices(cls) {
+    let serviceLoader = teavm_javaClass("java.util.ServiceLoader");
+    if (!serviceLoader.$$services$$) {
+        serviceLoader.$$services$$ = true;
+        teavm_fragment("fillServices");
+    }
+
+    let serviceList = cls.$$serviceList$$;
+    if (!serviceList) {
+        return $rt_createArray($rt_objcls(), 0);
+    }
+
+    let result = $rt_createArray($rt_objcls(), serviceList.length);
+    for (let i = 0; i < serviceList.length; ++i) {
+        let serviceDesc = serviceList[i];
+        let instance = new serviceDesc[0]();
+        serviceDesc[1](instance);
+        result.data[i] = instance;
+    }
+
+    return result;
+}

core/src/main/java/org/teavm/backend/javascript/JavaScriptTarget.java

@@ -171,7 +171,10 @@ public class JavaScriptTarget implements TeaVMTarget, TeaVMJavaScriptHost {
     public void setController(TeaVMTargetController controller) {
         this.controller = controller;
 
-        var weakRefGenerator = new WeakReferenceGenerator();
+        templateFactory = new JavaScriptTemplateFactory(controller.getClassLoader(),
+                controller.getDependencyInfo().getClassSource());
+
+        var weakRefGenerator = new WeakReferenceGenerator(templateFactory);
         methodGenerators.put(new MethodReference(WeakReference.class, "<init>", Object.class,
                 ReferenceQueue.class, void.class), weakRefGenerator);
         methodGenerators.put(new MethodReference(WeakReference.class, "get", Object.class), weakRefGenerator);
@@ -180,9 +183,6 @@ public class JavaScriptTarget implements TeaVMTarget, TeaVMJavaScriptHost {
         var refQueueGenerator = new ReferenceQueueGenerator();
         methodGenerators.put(new MethodReference(ReferenceQueue.class, "<init>", void.class), refQueueGenerator);
         methodGenerators.put(new MethodReference(ReferenceQueue.class, "poll", Reference.class), refQueueGenerator);
-
-        templateFactory = new JavaScriptTemplateFactory(controller.getClassLoader(),
-                controller.getDependencyInfo().getClassSource());
     }
 
     @Override
@@ -480,7 +480,6 @@ public class JavaScriptTarget implements TeaVMTarget, TeaVMJavaScriptHost {
 
             if (renderer.isLongLibraryUsed()) {
                 runtimeRenderer.renderHandWrittenRuntime("long.js");
-                renderer.renderLongRuntimeAliases();
             }
             if (renderer.isThreadLibraryUsed()) {
                 runtimeRenderer.renderHandWrittenRuntime("thread.js");
@@ -491,10 +490,10 @@ public class JavaScriptTarget implements TeaVMTarget, TeaVMJavaScriptHost {
             for (var entry : controller.getEntryPoints().entrySet()) {
                 sourceWriter.append("$rt_exports.").append(entry.getKey()).ws().append("=").ws();
                 var ref = entry.getValue().getMethod();
-                sourceWriter.append("$rt_mainStarter(").appendMethodBody(ref);
+                sourceWriter.appendFunction("$rt_mainStarter").append("(").appendMethodBody(ref);
                 sourceWriter.append(");").newLine();
                 sourceWriter.append("$rt_exports.").append(entry.getKey()).append(".").append("javaException")
-                        .ws().append("=").ws().append("$rt_javaException;").newLine();
+                        .ws().append("=").ws().appendFunction("$rt_javaException").append(";").newLine();
             }
 
             for (var listener : rendererListeners) {

core/src/main/java/org/teavm/backend/javascript/intrinsics/ref/ReferenceQueueGenerator.java

@@ -16,56 +16,33 @@
 package org.teavm.backend.javascript.intrinsics.ref;
 
 import java.io.IOException;
-import java.lang.ref.Reference;
-import java.lang.ref.ReferenceQueue;
 import org.teavm.backend.javascript.codegen.SourceWriter;
 import org.teavm.backend.javascript.spi.Generator;
 import org.teavm.backend.javascript.spi.GeneratorContext;
-import org.teavm.model.FieldReference;
+import org.teavm.backend.javascript.templating.JavaScriptTemplate;
+import org.teavm.backend.javascript.templating.JavaScriptTemplateFactory;
 import org.teavm.model.MethodReference;
 
 public class ReferenceQueueGenerator implements Generator {
-    private static final FieldReference INNER_FIELD = new FieldReference(ReferenceQueue.class.getName(), "inner");
+    private JavaScriptTemplate template;
-    private static final FieldReference REGISTRY_FIELD = new FieldReference(ReferenceQueue.class.getName(),
-            "registry");
-    private static final MethodReference REPORT_METHOD = new MethodReference(ReferenceQueue.class,
-            "reportNext", Reference.class, boolean.class);
 
     @Override
     public void generate(GeneratorContext context, SourceWriter writer, MethodReference methodRef) throws IOException {
+        ensureTemplate(context);
         switch (methodRef.getName()) {
             case "<init>":
-                generateInitMethod(context, writer);
+                template.builder("init").withContext(context).build().write(writer, 0);
                 break;
             case "poll":
-                generatePollMethod(context, writer);
+                template.builder("poll").withContext(context).build().write(writer, 0);
                 break;
         }
     }
 
-    private void generateInitMethod(GeneratorContext context, SourceWriter writer) throws IOException {
+    private void ensureTemplate(GeneratorContext context) throws IOException {
-        writer.append(context.getParameterName(0)).append(".").appendField(INNER_FIELD).ws().append("=")
+        if (template == null) {
-                .ws().append("[];").softNewLine();
+            template = new JavaScriptTemplateFactory(context.getClassLoader(), context.getClassSource())
-
+                    .createFromResource("org/teavm/classlib/java/lang/ref/ReferenceQueue.js");
-        if (context.getDependency().getMethod(REPORT_METHOD) != null) {
-            generateFinalizationRegistry(context, writer);
         }
     }
-
-    private void generateFinalizationRegistry(GeneratorContext context, SourceWriter writer) throws IOException {
-        writer.append(context.getParameterName(0)).append(".").appendField(REGISTRY_FIELD).ws().append("=")
-                .ws().append("new $rt_globals.FinalizationRegistry(ref").ws().append("=>").appendBlockStart();
-        writer.appendIf().append("!").appendMethodBody(REPORT_METHOD).append("(")
-                .append(context.getParameterName(0)).append(",").ws().append("ref))").ws();
-        writer.append(context.getParameterName(0)).append(".").appendField(INNER_FIELD)
-                .append(".push(ref)").softNewLine();
-        writer.appendBlockEnd().append(");").softNewLine();
-    }
-
-    private void generatePollMethod(GeneratorContext context, SourceWriter writer) throws IOException {
-        writer.append("var value").ws().append("=").ws().append(context.getParameterName(0))
-                .append(".").appendField(INNER_FIELD).append(".shift();").softNewLine();
-        writer.append("return typeof value").ws().append("!==").ws().append("'undefined'").ws()
-                .append("?").ws().append("value").ws().append(":").ws().append("null;").softNewLine();
-    }
 }

core/src/main/java/org/teavm/backend/javascript/intrinsics/ref/WeakReferenceGenerator.java

@@ -16,82 +16,34 @@
 package org.teavm.backend.javascript.intrinsics.ref;
 
 import java.io.IOException;
-import java.lang.ref.ReferenceQueue;
-import java.lang.ref.WeakReference;
 import org.teavm.backend.javascript.codegen.SourceWriter;
 import org.teavm.backend.javascript.spi.Generator;
 import org.teavm.backend.javascript.spi.GeneratorContext;
-import org.teavm.model.FieldReference;
+import org.teavm.backend.javascript.templating.JavaScriptTemplate;
+import org.teavm.backend.javascript.templating.JavaScriptTemplateFactory;
 import org.teavm.model.MethodReference;
 
 public class WeakReferenceGenerator implements Generator {
+    private JavaScriptTemplate template;
+
+    public WeakReferenceGenerator(JavaScriptTemplateFactory templateFactory) {
+        try {
+            template = templateFactory.createFromResource("org/teavm/classlib/java/lang/ref/WeakReference.js");
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
     @Override
     public void generate(GeneratorContext context, SourceWriter writer, MethodReference methodRef) throws IOException {
         switch (methodRef.getName()) {
             case "<init>":
-                generateConstructor(context, writer);
+                template.builder("init").withContext(context).build().write(writer, 0);
                 break;
             case "get":
-                generateGet(context, writer);
-                break;
             case "clear":
-                generateClear(context, writer);
+                template.builder(methodRef.getName()).withContext(context).build().write(writer, 0);
                 break;
         }
     }
-
-    private void generateConstructor(GeneratorContext context, SourceWriter writer) throws IOException {
-        writer.append("var supported").ws().append("=").ws();
-        isSupported(writer).append(";").softNewLine();
-        writer.append("var value").ws().append("=").ws().append("supported").ws()
-                .append("?").ws().append("new $rt_globals.WeakRef(")
-                .append(context.getParameterName(1)).append(")").ws();
-        writer.append(":").ws().append(context.getParameterName(0)).append(";").softNewLine();
-
-        writer.append(context.getParameterName(0)).append(".")
-                .appendField(new FieldReference(WeakReference.class.getName(), "value"))
-                .ws().append("=").ws().append("value;").softNewLine();
-
-        writer.appendIf().append(context.getParameterName(2)).ws().append("!==").ws().append("null")
-                .ws().append("&&").ws().append("supported)")
-                .appendBlockStart();
-
-        writer.append("var registry").ws().append("=").ws()
-                .append(context.getParameterName(2)).append(".")
-                .appendField(new FieldReference(ReferenceQueue.class.getName(), "registry")).append(";")
-                .softNewLine();
-        writer.appendIf().append("registry").ws().append("!==").ws().append("null)").ws();
-        writer.append("registry.register(").append(context.getParameterName(1))
-                .append(",").ws().append(context.getParameterName(0)).append(");").softNewLine();
-
-        writer.appendBlockEnd();
-    }
-
-    private void generateGet(GeneratorContext context, SourceWriter writer) throws IOException {
-        writer.append("var value").ws().append("=").ws().append(context.getParameterName(0)).append(".")
-                .appendField(new FieldReference(WeakReference.class.getName(), "value"))
-                .append(";").softNewLine();
-
-        writer.appendIf();
-        isSupported(writer).append(")").appendBlockStart();
-        writer.appendIf().append("value").ws().append("===").ws().append("null)")
-                .ws().append("return null;").softNewLine();
-        writer.append("var result").ws().append("=").ws().append("value.deref();").softNewLine();
-        writer.append("return typeof result").ws().append("!==").ws().append("'undefined'")
-                .ws().append("?").ws().append("result").ws().append(":").ws().append("null;").softNewLine();
-        writer.appendElse();
-        writer.append("return value;").softNewLine();
-        writer.appendBlockEnd();
-    }
-
-    private void generateClear(GeneratorContext context, SourceWriter writer) throws IOException {
-        writer.append(context.getParameterName(0)).append(".")
-                .appendField(new FieldReference(WeakReference.class.getName(), "value")).ws();
-        writer.append("=").ws().append("null;").softNewLine();
-    }
-
-    private SourceWriter isSupported(SourceWriter writer) throws IOException {
-        return writer.append("typeof ").append("$rt_globals.WeakRef").ws().append("!==").ws()
-                .append("'undefined'");
-    }
 }

core/src/main/java/org/teavm/backend/javascript/rendering/DefaultGlobalNameWriter.java

@@ -28,7 +28,7 @@ public class DefaultGlobalNameWriter implements Function<String, NameEmitter> {
     @Override
     public NameEmitter apply(String s) {
         if (s.startsWith("$rt_") || s.startsWith("Long_") || s.equals("Long")) {
-            return prec -> writer.append(s);
+            return prec -> writer.appendFunction(s);
         }
         return prec -> writer.append("$rt_globals").append('.').append(s);
     }

core/src/main/java/org/teavm/backend/javascript/rendering/Renderer.java

@@ -183,7 +183,7 @@ public class Renderer implements RenderingManager {
         }
         try {
             int start = writer.getOffset();
-            writer.append("$rt_stringPool([");
+            writer.appendFunction("$rt_stringPool").append("([");
             for (int i = 0; i < context.getStringPool().size(); ++i) {
                 if (i > 0) {
                     writer.append(',').ws();
@@ -223,9 +223,9 @@ public class Renderer implements RenderingManager {
     }
 
     private void renderJavaStringToString() throws IOException {
-        writer.appendClass("java.lang.String").append(".prototype.toString").ws().append("=").ws()
+        writer.appendClass("java.lang.String").append(".prototype.toString").ws().append("=").ws().append("()")
-                .append("function()").ws().append("{").indent().softNewLine();
+                .ws().append("=>").ws().append("{").indent().softNewLine();
-        writer.append("return $rt_ustr(this);").softNewLine();
+        writer.append("return ").appendFunction("$rt_ustr").append("(this);").softNewLine();
         writer.outdent().append("};").newLine();
         writer.appendClass("java.lang.String").append(".prototype.valueOf").ws().append("=").ws()
             .appendClass("java.lang.String").append(".prototype.toString;").softNewLine();
@@ -233,8 +233,9 @@ public class Renderer implements RenderingManager {
 
     private void renderJavaObjectToString() throws IOException {
         writer.appendClass("java.lang.Object").append(".prototype.toString").ws().append("=").ws()
-                .append("function()").ws().append("{").indent().softNewLine();
+                .append("()").ws().append("=>").ws().append("{").indent().softNewLine();
-        writer.append("return $rt_ustr(").appendMethodBody(Object.class, "toString", String.class).append("(this));")
+        writer.append("return ").appendFunction("$rt_ustr").append("(")
+                .appendMethodBody(Object.class, "toString", String.class).append("(this));")
                 .softNewLine();
         writer.outdent().append("};").newLine();
     }
@@ -242,7 +243,7 @@ public class Renderer implements RenderingManager {
     private void renderTeaVMClass() throws IOException {
         writer.appendClass("java.lang.Object").append(".prototype.__teavm_class__").ws().append("=").ws()
                 .append("function()").ws().append("{").indent().softNewLine();
-        writer.append("return $dbg_class(this);").softNewLine();
+        writer.append("return ").appendFunction("$dbg_class").append("(this);").softNewLine();
         writer.outdent().append("};").newLine();
     }
 
@@ -250,42 +251,6 @@ public class Renderer implements RenderingManager {
         sizeByClass.put(className, sizeByClass.getOrDefault(className, 0) + sz);
     }
 
-    private void renderCommonRuntimeAliases() throws IOException {
-        renderRuntimeAliases("$rt_throw", "$rt_compare", "$rt_nullCheck", "$rt_cls", "$rt_createArray",
-                "$rt_isInstance", "$rt_nativeThread", "$rt_suspending", "$rt_resuming", "$rt_invalidPointer",
-                "$rt_s", "$rt_eraseClinit", "$rt_imul", "$rt_wrapException", "$rt_checkBounds",
-                "$rt_checkUpperBound", "$rt_checkLowerBound", "$rt_wrapFunction0", "$rt_wrapFunction1",
-                "$rt_wrapFunction2", "$rt_wrapFunction3", "$rt_wrapFunction4",
-                "$rt_classWithoutFields", "$rt_createArrayFromData", "$rt_createCharArrayFromData",
-                "$rt_createByteArrayFromData", "$rt_createShortArrayFromData", "$rt_createIntArrayFromData",
-                "$rt_createBooleanArrayFromData", "$rt_createFloatArrayFromData", "$rt_createDoubleArrayFromData",
-                "$rt_createLongArrayFromData", "$rt_createBooleanArray", "$rt_createByteArray",
-                "$rt_createShortArray", "$rt_createCharArray", "$rt_createIntArray", "$rt_createLongArray",
-                "$rt_createFloatArray", "$rt_createDoubleArray", "$rt_compare",
-                "$rt_castToClass", "$rt_castToInterface", "$rt_equalDoubles",
-                "$rt_str", "Long_toNumber", "Long_fromInt", "Long_fromNumber", "Long_create", "Long_ZERO",
-                "$rt_intern", "$rt_substring", "$rt_ustr",
-                "Long_hi", "Long_lo");
-    }
-
-    public void renderLongRuntimeAliases() throws IOException {
-        renderRuntimeAliases("Long_add", "Long_sub", "Long_mul", "Long_div", "Long_rem", "Long_or", "Long_and",
-                "Long_xor", "Long_shl", "Long_shr", "Long_shru", "Long_compare", "Long_eq", "Long_ne",
-                "Long_lt", "Long_le", "Long_gt", "Long_ge", "Long_not", "Long_neg");
-    }
-
-    private void renderRuntimeAliases(String... names) throws IOException {
-        boolean first = true;
-        for (String name : names) {
-            if (!first) {
-                writer.softNewLine();
-            }
-            first = false;
-            writer.append("var ").appendFunction(name).ws().append('=').ws().append(name).append(";").softNewLine();
-        }
-        writer.newLine();
-    }
-
     public void prepare(List<PreparedClass> classes) {
         if (minifying) {
             NamingOrderer orderer = new NamingOrderer();
@@ -300,13 +265,6 @@ public class Renderer implements RenderingManager {
     }
 
     public boolean render(List<PreparedClass> classes) throws RenderingException {
-        if (minifying) {
-            try {
-                renderCommonRuntimeAliases();
-            } catch (IOException e) {
-                throw new RenderingException(e);
-            }
-        }
         int index = 0;
         for (PreparedClass cls : classes) {
             int start = writer.getOffset();
@@ -527,7 +485,7 @@ public class Renderer implements RenderingManager {
 
         int start = writer.getOffset();
         try {
-            writer.append("$rt_packages([");
+            writer.appendFunction("$rt_packages").append("([");
             ObjectIntMap<String> packageIndexes = generatePackageMetadata(classes, metadataRequirements);
             writer.append("]);").newLine();
 
@@ -545,7 +503,7 @@ public class Renderer implements RenderingManager {
 
     private void renderClassMetadataPortion(List<PreparedClass> classes, ObjectIntMap<String> packageIndexes,
             ClassMetadataRequirements metadataRequirements) throws IOException {
-        writer.append("$rt_metadata([");
+        writer.appendFunction("$rt_metadata").append("([");
         boolean first = true;
         for (PreparedClass cls : classes) {
             if (!first) {

core/src/main/java/org/teavm/backend/javascript/rendering/RenderingContext.java

@@ -305,40 +305,40 @@ public abstract class RenderingContext {
         }
 
         for (int i = 0; i < arrayCount; ++i) {
-            writer.append("$rt_arraycls(");
+            writer.appendFunction("$rt_arraycls").append("(");
         }
 
         if (type instanceof ValueType.Object) {
             ValueType.Object objType = (ValueType.Object) type;
             writer.appendClass(objType.getClassName());
         } else if (type instanceof ValueType.Void) {
-            writer.append("$rt_voidcls");
+            writer.appendFunction("$rt_voidcls");
         } else if (type instanceof ValueType.Primitive) {
             ValueType.Primitive primitiveType = (ValueType.Primitive) type;
             switch (primitiveType.getKind()) {
                 case BOOLEAN:
-                    writer.append("$rt_booleancls");
+                    writer.appendFunction("$rt_booleancls");
                     break;
                 case CHARACTER:
-                    writer.append("$rt_charcls");
+                    writer.appendFunction("$rt_charcls");
                     break;
                 case BYTE:
-                    writer.append("$rt_bytecls");
+                    writer.appendFunction("$rt_bytecls");
                     break;
                 case SHORT:
-                    writer.append("$rt_shortcls");
+                    writer.appendFunction("$rt_shortcls");
                     break;
                 case INTEGER:
-                    writer.append("$rt_intcls");
+                    writer.appendFunction("$rt_intcls");
                     break;
                 case LONG:
-                    writer.append("$rt_longcls");
+                    writer.appendFunction("$rt_longcls");
                     break;
                 case FLOAT:
-                    writer.append("$rt_floatcls");
+                    writer.appendFunction("$rt_floatcls");
                     break;
                 case DOUBLE:
-                    writer.append("$rt_doublecls");
+                    writer.appendFunction("$rt_doublecls");
                     break;
                 default:
                     throw new IllegalArgumentException("The type is not renderable");

core/src/main/java/org/teavm/backend/javascript/rendering/StatementRenderer.java

@@ -1414,32 +1414,32 @@ public class StatementRenderer implements ExprVisitor, StatementVisitor {
             if (type instanceof ValueType.Primitive) {
                 switch (((ValueType.Primitive) type).getKind()) {
                     case BOOLEAN:
-                        writer.append("$rt_createBooleanMultiArray(");
+                        writer.appendFunction("$rt_createBooleanMultiArray").append("(");
                         break;
                     case BYTE:
-                        writer.append("$rt_createByteMultiArray(");
+                        writer.appendFunction("$rt_createByteMultiArray").append("(");
                         break;
                     case SHORT:
-                        writer.append("$rt_createShortMultiArray(");
+                        writer.appendFunction("$rt_createShortMultiArray").append("(");
                         break;
                     case INTEGER:
-                        writer.append("$rt_createIntMultiArray(");
+                        writer.appendFunction("$rt_createIntMultiArray").append("(");
                         break;
                     case LONG:
-                        writer.append("$rt_createLongMultiArray(");
+                        writer.appendFunction("$rt_createLongMultiArray").append("(");
                         break;
                     case FLOAT:
-                        writer.append("$rt_createFloatMultiArray(");
+                        writer.appendFunction("$rt_createFloatMultiArray").append("(");
                         break;
                     case DOUBLE:
-                        writer.append("$rt_createDoubleMultiArray(");
+                        writer.appendFunction("$rt_createDoubleMultiArray").append("(");
                         break;
                     case CHARACTER:
-                        writer.append("$rt_createCharMultiArray(");
+                        writer.appendFunction("$rt_createCharMultiArray").append("(");
                         break;
                 }
             } else {
-                writer.append("$rt_createMultiArray(");
+                writer.appendFunction("$rt_createMultiArray").append("(");
                 context.typeToClsString(writer, type);
                 writer.append(",").ws();
             }

core/src/main/java/org/teavm/backend/javascript/templating/JavaScriptTemplate.java

@@ -16,6 +16,7 @@
 package org.teavm.backend.javascript.templating;
 
 import java.util.HashMap;
+import java.util.Map;
 import java.util.function.IntFunction;
 import org.mozilla.javascript.ast.AstNode;
 import org.mozilla.javascript.ast.FunctionNode;
@@ -42,6 +43,7 @@ public class JavaScriptTemplate {
     public static class FragmentBuilder {
         private FunctionNode node;
         private IntFunction<SourceFragment> parameters;
+        private Map<String, SourceFragment> fragments = new HashMap<>();
 
         private FragmentBuilder(FunctionNode node) {
             this.node = node;
@@ -53,7 +55,12 @@ public class JavaScriptTemplate {
         }
 
         public FragmentBuilder withContext(GeneratorContext context) {
-            return withParameters(param -> (writer, precedence) -> writer.append(context.getParameterName(param + 1)));
+            return withParameters(param -> (writer, precedence) -> writer.append(context.getParameterName(param)));
+        }
+
+        public FragmentBuilder withFragment(String name, SourceFragment fragment) {
+            fragments.put(name, fragment);
+            return this;
         }
 
         public SourceFragment build() {
@@ -62,13 +69,16 @@ public class JavaScriptTemplate {
             for (var i = 0; i < node.getParams().size(); ++i) {
                 var param = node.getParams().get(i);
                 if (param instanceof Name) {
-                    nameParameters.put(((Name) param).getIdentifier(), intParameters.apply(i));
+                    nameParameters.put(((Name) param).getIdentifier(), intParameters.apply(i + 1));
                 }
             }
             var thisFragment = parameters.apply(0);
             var body = node.getBody();
             return (writer, precedence) -> {
                 var astWriter = new TemplatingAstWriter(writer, nameParameters, node);
+                for (var entry : fragments.entrySet()) {
+                    astWriter.setFragment(entry.getKey(), entry.getValue());
+                }
                 if (node.getSymbolTable() != null) {
                     for (var name : node.getSymbolTable().keySet()) {
                         astWriter.currentScopes.put(name, node);

core/src/main/java/org/teavm/backend/javascript/templating/TemplatingAstWriter.java

@@ -16,6 +16,7 @@
 package org.teavm.backend.javascript.templating;
 
 import java.io.IOException;
+import java.util.HashMap;
 import java.util.Map;
 import org.mozilla.javascript.ast.ElementGet;
 import org.mozilla.javascript.ast.FunctionCall;
@@ -34,6 +35,7 @@ import org.teavm.model.MethodReference;
 public class TemplatingAstWriter extends AstWriter {
     private Map<String, SourceFragment> names;
     private Scope scope;
+    private Map<String, SourceFragment> fragments = new HashMap<>();
 
     public TemplatingAstWriter(SourceWriter writer, Map<String, SourceFragment> names, Scope scope) {
         super(writer, new DefaultGlobalNameWriter(writer));
@@ -49,6 +51,10 @@ public class TemplatingAstWriter extends AstWriter {
         }
     }
 
+    public void setFragment(String name, SourceFragment fragment) {
+        fragments.put(name, fragment);
+    }
+
     @Override
     protected boolean intrinsic(FunctionCall node, int precedence) throws IOException {
         if (node.getTarget() instanceof Name) {
@@ -70,6 +76,8 @@ public class TemplatingAstWriter extends AstWriter {
                 return writeJavaConstructor(node);
             case "teavm_javaClassInit":
                 return writeJavaClassInit(node);
+            case "teavm_fragment":
+                return writeFragment(node);
             default:
                 return false;
         }
@@ -129,6 +137,19 @@ public class TemplatingAstWriter extends AstWriter {
         return true;
     }
 
+    private boolean writeFragment(FunctionCall node) throws IOException {
+        if (node.getArguments().size() != 1) {
+            return false;
+        }
+        var fragmentArg = node.getArguments().get(0);
+        if (!(fragmentArg instanceof StringLiteral)) {
+            return false;
+        }
+        var fragment = fragments.get(((StringLiteral) fragmentArg).getValue());
+        fragment.write(writer, AstWriter.PRECEDENCE_COMMA + 1);
+        return true;
+    }
+
     @Override
     protected void print(ElementGet node) throws IOException {
         if (node.getElement() instanceof FunctionCall) {
@@ -209,7 +230,7 @@ public class TemplatingAstWriter extends AstWriter {
                     return;
                 }
             }
-            if (definingScope == null && scope != null) {
+            if (definingScope == null) {
                 writer.appendFunction(node.getIdentifier());
                 return;
             }

core/src/main/resources/org/teavm/backend/javascript/intern.js

@@ -18,11 +18,11 @@
 var $rt_intern
 if (teavm_javaMethodExists("java.lang.String", "intern()Ljava/lang/String;")) {
     $rt_intern = function() {
-        var map = Object.create(null);
+        var map = teavm_globals.Object.create(null);
 
         var get;
-        if (typeof WeakRef !== 'undefined') {
+        if (typeof teavm_globals.WeakRef !== 'undefined') {
-            var registry = new FinalizationRegistry(value => {
+            var registry = new teavm_globals.FinalizationRegistry(value => {
                 delete map[value];
             });
 
@@ -32,7 +32,7 @@ if (teavm_javaMethodExists("java.lang.String", "intern()Ljava/lang/String;")) {
                 var result = typeof ref !== 'undefined' ? ref.deref() : void 0;
                 if (typeof result !== 'object') {
                     result = str;
-                    map[key] = new WeakRef(result);
+                    map[key] = new teavm_globals.WeakRef(result);
                     registry.register(result, key);
                 }
                 return result;

core/src/main/resources/org/teavm/backend/javascript/long.js

@@ -41,7 +41,7 @@ var Long_shr;
 var Long_shru;
 var Long_not;
 
-if (typeof BigInt !== 'function') {
+if (typeof teavm_globals.BigInt !== 'function') {
     Long_eq = function(a, b) {
         return a.hi === b.hi && a.lo === b.lo;
     }
@@ -267,7 +267,7 @@ if (typeof BigInt !== 'function') {
 
     function Long_divRem(a, b) {
         if (b.lo === 0 && b.hi === 0) {
-            throw new Error("Division by zero");
+            throw new teavm_globals.Error("Division by zero");
         }
         var positive = Long_isNegative(a) === Long_isNegative(b);
         if (Long_isNegative(a)) {
@@ -286,7 +286,7 @@ if (typeof BigInt !== 'function') {
 
     function Long_udivRem(a, b) {
         if (b.lo === 0 && b.hi === 0) {
-            throw new Error("Division by zero");
+            throw new teavm_globals.Error("Division by zero");
         }
         a = new LongInt(a.lo, a.hi, 0);
         b = new LongInt(b.lo, b.hi, 0);
@@ -599,79 +599,81 @@ if (typeof BigInt !== 'function') {
     }
 
     Long_add = function(a, b) {
-        return BigInt.asIntN(64, a + b);
+        return teavm_globals.BigInt.asIntN(64, a + b);
     }
 
     Long_inc = function(a) {
-        return BigInt.asIntN(64, a + 1);
+        return teavm_globals.BigInt.asIntN(64, a + 1);
     }
 
     Long_dec = function(a) {
-        return BigInt.asIntN(64, a - 1);
+        return teavm_globals.BigInt.asIntN(64, a - 1);
     }
 
     Long_neg = function(a) {
-        return BigInt.asIntN(64, -a);
+        return teavm_globals.BigInt.asIntN(64, -a);
     }
 
     Long_sub = function(a, b) {
-        return BigInt.asIntN(64, a - b);
+        return teavm_globals.BigInt.asIntN(64, a - b);
     }
 
     Long_compare = function(a, b) {
         return a < b ? -1 : a > b ? 1 : 0;
     }
     Long_ucompare = function(a, b) {
-        a = BigInt.asUintN(64, a);
+        a = teavm_globals.BigInt.asUintN(64, a);
-        b = BigInt.asUintN(64, b);
+        b = teavm_globals.BigInt.asUintN(64, b);
         return a < b ? -1 : a > b ? 1 : 0;
     }
 
     Long_mul = function(a, b) {
-        return BigInt.asIntN(64, a * b);
+        return teavm_globals.BigInt.asIntN(64, a * b);
     }
 
     Long_div = function(a, b) {
-        return BigInt.asIntN(64, a / b);
+        return teavm_globals.BigInt.asIntN(64, a / b);
     }
 
     Long_udiv = function(a, b) {
-        return BigInt.asIntN(64, BigInt.asUintN(64, a) / BigInt.asUintN(64, b));
+        return teavm_globals.BigInt.asIntN(64, teavm_globals.BigInt.asUintN(64, a) /
+            teavm_globals.BigInt.asUintN(64, b));
     }
 
     Long_rem = function(a, b) {
-        return BigInt.asIntN(64, a % b);
+        return teavm_globals.BigInt.asIntN(64, a % b);
     }
 
     Long_urem = function(a, b) {
-        return BigInt.asIntN(64, BigInt.asUintN(64, a) % BigInt.asUintN(64, b));
+        return teavm_globals.BigInt.asIntN(64, teavm_globals.BigInt.asUintN(64, a) %
+            teavm_globals.BigInt.asUintN(64, b));
     }
 
     Long_and = function(a, b) {
-        return BigInt.asIntN(64, a & b);
+        return teavm_globals.BigInt.asIntN(64, a & b);
     }
 
     Long_or = function(a, b) {
-        return BigInt.asIntN(64, a | b);
+        return teavm_globals.BigInt.asIntN(64, a | b);
     }
 
     Long_xor = function(a, b) {
-        return BigInt.asIntN(64, a ^ b);
+        return teavm_globals.BigInt.asIntN(64, a ^ b);
     }
 
     Long_shl = function(a, b) {
-        return BigInt.asIntN(64, a << BigInt(b & 63));
+        return teavm_globals.BigInt.asIntN(64, a << teavm_globals.BigInt(b & 63));
     }
 
     Long_shr = function(a, b) {
-        return BigInt.asIntN(64, a >> BigInt(b & 63));
+        return teavm_globals.BigInt.asIntN(64, a >> teavm_globals.BigInt(b & 63));
     }
 
     Long_shru = function(a, b) {
-        return BigInt.asIntN(64, BigInt.asUintN(64, a) >> BigInt(b & 63));
+        return teavm_globals.BigInt.asIntN(64, teavm_globals.BigInt.asUintN(64, a) >> teavm_globals.BigInt(b & 63));
     }
 
     Long_not = function(a) {
-        return BigInt.asIntN(64, ~a);
+        return teavm_globals.BigInt.asIntN(64, ~a);
     }
 }

core/src/main/resources/org/teavm/backend/javascript/runtime.js

@@ -57,7 +57,7 @@ function $rt_castToClass(obj, cls) {
     return obj;
 }
 function $rt_createArray(cls, sz) {
-    var data = new Array(sz);
+    var data = new teavm_globals.Array(sz);
     data.fill(null);
     return new ($rt_arraycls(cls))(data);
 }
@@ -68,13 +68,13 @@ function $rt_wrapArray(cls, data) {
     return new ($rt_arraycls(cls))(data);
 }
 function $rt_createUnfilledArray(cls, sz) {
-    return new ($rt_arraycls(cls))(new Array(sz));
+    return new ($rt_arraycls(cls))(new teavm_globals.Array(sz));
 }
 var $rt_createLongArray;
 var $rt_createLongArrayFromData;
-if (typeof BigInt64Array !== 'function') {
+if (typeof teavm_globals.BigInt64Array !== 'function') {
     $rt_createLongArray = function(sz) {
-        var data = new Array(sz);
+        var data = new teavm_globals.Array(sz);
         var arr = new $rt_longArrayCls(data);
         data.fill(Long_ZERO);
         return arr;
@@ -84,69 +84,69 @@ if (typeof BigInt64Array !== 'function') {
     }
 } else {
     $rt_createLongArray = function (sz) {
-        return new $rt_longArrayCls(new BigInt64Array(sz));
+        return new $rt_longArrayCls(new teavm_globals.BigInt64Array(sz));
     }
     $rt_createLongArrayFromData = function(data) {
-        var buffer = new BigInt64Array(data.length);
+        var buffer = new teavm_globals.BigInt64Array(data.length);
         buffer.set(data);
         return new $rt_longArrayCls(buffer);
     }
 }
 
 function $rt_createCharArray(sz) {
-    return new $rt_charArrayCls(new Uint16Array(sz));
+    return new $rt_charArrayCls(new teavm_globals.Uint16Array(sz));
 }
 function $rt_createCharArrayFromData(data) {
-    var buffer = new Uint16Array(data.length);
+    var buffer = new teavm_globals.Uint16Array(data.length);
     buffer.set(data);
     return new $rt_charArrayCls(buffer);
 }
 function $rt_createByteArray(sz) {
-    return new $rt_byteArrayCls(new Int8Array(sz));
+    return new $rt_byteArrayCls(new teavm_globals.Int8Array(sz));
 }
 function $rt_createByteArrayFromData(data) {
-    var buffer = new Int8Array(data.length);
+    var buffer = new teavm_globals.Int8Array(data.length);
     buffer.set(data);
     return new $rt_byteArrayCls(buffer);
 }
 function $rt_createShortArray(sz) {
-    return new $rt_shortArrayCls(new Int16Array(sz));
+    return new $rt_shortArrayCls(new teavm_globals.Int16Array(sz));
 }
 function $rt_createShortArrayFromData(data) {
-    var buffer = new Int16Array(data.length);
+    var buffer = new teavm_globals.Int16Array(data.length);
     buffer.set(data);
     return new $rt_shortArrayCls(buffer);
 }
 function $rt_createIntArray(sz) {
-    return new $rt_intArrayCls(new Int32Array(sz));
+    return new $rt_intArrayCls(new teavm_globals.Int32Array(sz));
 }
 function $rt_createIntArrayFromData(data) {
-    var buffer = new Int32Array(data.length);
+    var buffer = new teavm_globals.Int32Array(data.length);
     buffer.set(data);
     return new $rt_intArrayCls(buffer);
 }
 function $rt_createBooleanArray(sz) {
-    return new $rt_booleanArrayCls(new Int8Array(sz));
+    return new $rt_booleanArrayCls(new teavm_globals.Int8Array(sz));
 }
 function $rt_createBooleanArrayFromData(data) {
-    var buffer = new Int8Array(data.length);
+    var buffer = new teavm_globals.Int8Array(data.length);
     buffer.set(data);
     return new $rt_booleanArrayCls(buffer);
 }
 
 function $rt_createFloatArray(sz) {
-    return new $rt_floatArrayCls(new Float32Array(sz));
+    return new $rt_floatArrayCls(new teavm_globals.Float32Array(sz));
 }
 function $rt_createFloatArrayFromData(data) {
-    var buffer = new Float32Array(data.length);
+    var buffer = new teavm_globals.Float32Array(data.length);
     buffer.set(data);
     return new $rt_floatArrayCls(buffer);
 }
 function $rt_createDoubleArray(sz) {
-    return new $rt_doubleArrayCls(new Float64Array(sz));
+    return new $rt_doubleArrayCls(new teavm_globals.Float64Array(sz));
 }
 function $rt_createDoubleArrayFromData(data) {
-    var buffer = new Float64Array(data.length);
+    var buffer = new teavm_globals.Float64Array(data.length);
     buffer.set(data);
     return new $rt_doubleArrayCls(buffer);
 }
@@ -158,7 +158,7 @@ function $rt_arraycls(cls) {
             $rt_objcls().call(this);
             this.data = data;
         }
-        JavaArray.prototype = Object.create($rt_objcls().prototype);
+        JavaArray.prototype = teavm_globals.Object.create($rt_objcls().prototype);
         JavaArray.prototype.type = cls;
         JavaArray.prototype.constructor = JavaArray;
         JavaArray.prototype.toString = function() {
@@ -239,16 +239,16 @@ var $rt_voidcls = $rt_createPrimitiveCls("void", "V");
 function $rt_throw(ex) {
     throw $rt_exception(ex);
 }
-var $rt_javaExceptionProp = Symbol("javaException")
+var $rt_javaExceptionProp = teavm_globals.Symbol("javaException")
 function $rt_exception(ex) {
     var err = ex.$jsException;
     if (!err) {
         var javaCause = $rt_throwableCause(ex);
-        var jsCause = javaCause !== null ? javaCause.$jsException : undefined;
+        var jsCause = javaCause !== null ? javaCause.$jsException : void 0;
-        var cause = typeof jsCause === "object" ? { cause : jsCause } : undefined;
+        var cause = typeof jsCause === "object" ? { cause : jsCause } : void 0;
         err = new JavaError("Java exception thrown", cause);
-        if (typeof Error.captureStackTrace === "function") {
+        if (typeof teavm_globals.Error.captureStackTrace === "function") {
-            Error.captureStackTrace(err);
+            teavm_globals.Error.captureStackTrace(err);
         }
         err[$rt_javaExceptionProp] = ex;
         ex.$jsException = err;
@@ -293,7 +293,7 @@ function $rt_createMultiArray(cls, dimensions) {
             return $rt_createArray(cls, dimensions[first]);
         }
     }
-    var arrays = new Array($rt_primitiveArrayCount(dimensions, first));
+    var arrays = new teavm_globals.Array($rt_primitiveArrayCount(dimensions, first));
     var firstDim = dimensions[first] | 0;
     for (i = 0; i < arrays.length; i = (i + 1) | 0) {
         arrays[i] = $rt_createArray(cls, firstDim);
@@ -301,7 +301,7 @@ function $rt_createMultiArray(cls, dimensions) {
     return $rt_createMultiArrayImpl(cls, arrays, dimensions, first);
 }
 function $rt_createByteMultiArray(dimensions) {
-    var arrays = new Array($rt_primitiveArrayCount(dimensions, 0));
+    var arrays = new teavm_globals.Array($rt_primitiveArrayCount(dimensions, 0));
     if (arrays.length === 0) {
         return $rt_createMultiArray($rt_bytecls, dimensions);
     }
@@ -312,7 +312,7 @@ function $rt_createByteMultiArray(dimensions) {
     return $rt_createMultiArrayImpl($rt_bytecls, arrays, dimensions);
 }
 function $rt_createCharMultiArray(dimensions) {
-    var arrays = new Array($rt_primitiveArrayCount(dimensions, 0));
+    var arrays = new teavm_globals.Array($rt_primitiveArrayCount(dimensions, 0));
     if (arrays.length === 0) {
         return $rt_createMultiArray($rt_charcls, dimensions);
     }
@@ -323,7 +323,7 @@ function $rt_createCharMultiArray(dimensions) {
     return $rt_createMultiArrayImpl($rt_charcls, arrays, dimensions, 0);
 }
 function $rt_createBooleanMultiArray(dimensions) {
-    var arrays = new Array($rt_primitiveArrayCount(dimensions, 0));
+    var arrays = new teavm_globals.Array($rt_primitiveArrayCount(dimensions, 0));
     if (arrays.length === 0) {
         return $rt_createMultiArray($rt_booleancls, dimensions);
     }
@@ -334,7 +334,7 @@ function $rt_createBooleanMultiArray(dimensions) {
     return $rt_createMultiArrayImpl($rt_booleancls, arrays, dimensions, 0);
 }
 function $rt_createShortMultiArray(dimensions) {
-    var arrays = new Array($rt_primitiveArrayCount(dimensions, 0));
+    var arrays = new teavm_globals.Array($rt_primitiveArrayCount(dimensions, 0));
     if (arrays.length === 0) {
         return $rt_createMultiArray($rt_shortcls, dimensions);
     }
@@ -345,7 +345,7 @@ function $rt_createShortMultiArray(dimensions) {
     return $rt_createMultiArrayImpl($rt_shortcls, arrays, dimensions, 0);
 }
 function $rt_createIntMultiArray(dimensions) {
-    var arrays = new Array($rt_primitiveArrayCount(dimensions, 0));
+    var arrays = new teavm_globals.Array($rt_primitiveArrayCount(dimensions, 0));
     if (arrays.length === 0) {
         return $rt_createMultiArray($rt_intcls, dimensions);
     }
@@ -356,7 +356,7 @@ function $rt_createIntMultiArray(dimensions) {
     return $rt_createMultiArrayImpl($rt_intcls, arrays, dimensions, 0);
 }
 function $rt_createLongMultiArray(dimensions) {
-    var arrays = new Array($rt_primitiveArrayCount(dimensions, 0));
+    var arrays = new teavm_globals.Array($rt_primitiveArrayCount(dimensions, 0));
     if (arrays.length === 0) {
         return $rt_createMultiArray($rt_longcls, dimensions);
     }
@@ -367,7 +367,7 @@ function $rt_createLongMultiArray(dimensions) {
     return $rt_createMultiArrayImpl($rt_longcls, arrays, dimensions, 0);
 }
 function $rt_createFloatMultiArray(dimensions) {
-    var arrays = new Array($rt_primitiveArrayCount(dimensions, 0));
+    var arrays = new teavm_globals.Array($rt_primitiveArrayCount(dimensions, 0));
     if (arrays.length === 0) {
         return $rt_createMultiArray($rt_floatcls, dimensions);
     }
@@ -378,7 +378,7 @@ function $rt_createFloatMultiArray(dimensions) {
     return $rt_createMultiArrayImpl($rt_floatcls, arrays, dimensions, 0);
 }
 function $rt_createDoubleMultiArray(dimensions) {
-    var arrays = new Array($rt_primitiveArrayCount(dimensions, 0));
+    var arrays = new teavm_globals.Array($rt_primitiveArrayCount(dimensions, 0));
     if (arrays.length === 0) {
         return $rt_createMultiArray($rt_doublecls, dimensions);
     }
@@ -477,7 +477,7 @@ var $rt_putStderr = typeof $rt_putStderrCustom === "function"
 var $rt_packageData = null;
 function $rt_packages(data) {
     var i = 0;
-    var packages = new Array(data.length);
+    var packages = new teavm_globals.Array(data.length);
     for (var j = 0; j < data.length; ++j) {
         var prefixIndex = data[i++];
         var prefix = prefixIndex >= 0 ? packages[prefixIndex] : "";
@@ -508,7 +508,7 @@ function $rt_metadata(data) {
         m.supertypes = data[i++];
         if (m.superclass) {
             m.supertypes.push(m.superclass);
-            cls.prototype = Object.create(m.superclass.prototype);
+            cls.prototype = teavm_globals.Object.create(m.superclass.prototype);
         } else {
             cls.prototype = {};
         }
@@ -583,7 +583,7 @@ function $rt_wrapFunction4(f) {
 }
 function $rt_threadStarter(f) {
     return function() {
-        var args = Array.prototype.slice.apply(arguments);
+        var args = teavm_globals.Array.prototype.slice.apply(arguments);
         $rt_startThread(function() {
             f.apply(this, args);
         });
@@ -604,7 +604,7 @@ function $rt_mainStarter(f) {
 var $rt_stringPool_instance;
 function $rt_stringPool(strings) {
     $rt_stringClassInit();
-    $rt_stringPool_instance = new Array(strings.length);
+    $rt_stringPool_instance = new teavm_globals.Array(strings.length);
     for (var i = 0; i < strings.length; ++i) {
         $rt_stringPool_instance[i] = $rt_intern($rt_str(strings[i]));
     }
@@ -616,15 +616,15 @@ function $rt_eraseClinit(target) {
     return target.$clinit = function() {};
 }
 
-var $rt_numberConversionBuffer = new ArrayBuffer(16);
+var $rt_numberConversionBuffer = new teavm_globals.ArrayBuffer(16);
-var $rt_numberConversionView = new DataView($rt_numberConversionBuffer);
+var $rt_numberConversionView = new teavm_globals.DataView($rt_numberConversionBuffer);
-var $rt_numberConversionFloatArray = new Float32Array($rt_numberConversionBuffer);
+var $rt_numberConversionFloatArray = new teavm_globals.Float32Array($rt_numberConversionBuffer);
-var $rt_numberConversionDoubleArray = new Float64Array($rt_numberConversionBuffer);
+var $rt_numberConversionDoubleArray = new teavm_globals.Float64Array($rt_numberConversionBuffer);
-var $rt_numberConversionIntArray = new Int32Array($rt_numberConversionBuffer);
+var $rt_numberConversionIntArray = new teavm_globals.Int32Array($rt_numberConversionBuffer);
 
 var $rt_doubleToRawLongBits;
 var $rt_longBitsToDouble;
-if (typeof BigInt !== 'function') {
+if (typeof teavm_globals.BigInt !== 'function') {
     $rt_doubleToRawLongBits = function(n) {
         $rt_numberConversionView.setFloat64(0, n, true);
         return new Long($rt_numberConversionView.getInt32(0, true), $rt_numberConversionView.getInt32(4, true));
@@ -634,21 +634,23 @@ if (typeof BigInt !== 'function') {
         $rt_numberConversionView.setInt32(4, n.hi, true);
         return $rt_numberConversionView.getFloat64(0, true);
     }
-} else if (typeof BigInt64Array !== 'function') {
+} else if (typeof teavm_globals.BigInt64Array !== 'function') {
     $rt_doubleToRawLongBits = function(n) {
         $rt_numberConversionView.setFloat64(0, n, true);
         var lo = $rt_numberConversionView.getInt32(0, true);
         var hi = $rt_numberConversionView.getInt32(4, true);
-        return BigInt.asIntN(64, BigInt.asUintN(32, BigInt(lo)) | (BigInt(hi) << BigInt(32)));
+        return teavm_globals.BigInt.asIntN(64, teavm_globals.BigInt.asUintN(32, teavm_globals.BigInt(lo))
+            | (teavm_globals.BigInt(hi) << teavm_globals.BigInt(32)));
     }
     $rt_longBitsToDouble = function(n) {
         $rt_numberConversionView.setFloat64(0, n, true);
         var lo = $rt_numberConversionView.getInt32(0, true);
         var hi = $rt_numberConversionView.getInt32(4, true);
-        return BigInt.asIntN(64, BigInt.asUintN(32, BigInt(lo)) | (BigInt(hi) << BigInt(32)));
+        return teavm_globals.BigInt.asIntN(64, teavm_globals.BigInt.asUintN(32, teavm_globals.BigInt(lo))
+            | (teavm_globals.BigInt(hi) << teavm_globals.BigInt(32)));
     }
 } else {
-    var $rt_numberConversionLongArray = new BigInt64Array($rt_numberConversionBuffer);
+    var $rt_numberConversionLongArray = new teavm_globals.BigInt64Array($rt_numberConversionBuffer);
     $rt_doubleToRawLongBits = function(n) {
         $rt_numberConversionDoubleArray[0] = n;
         return $rt_numberConversionLongArray[0];
@@ -679,14 +681,14 @@ function $rt_equalDoubles(a, b) {
 
 var JavaError;
 if (typeof Reflect === 'object') {
-    var defaultMessage = Symbol("defaultMessage");
+    var defaultMessage = teavm_globals.Symbol("defaultMessage");
     JavaError = function JavaError(message, cause) {
-        var self = Reflect.construct(Error, [undefined, cause], JavaError);
+        var self = teavm_globals.Reflect.construct(teavm_globals.Error, [void 0, cause], JavaError);
-        Object.setPrototypeOf(self, JavaError.prototype);
+        teavm_globals.Object.setPrototypeOf(self, JavaError.prototype);
         self[defaultMessage] = message;
         return self;
     }
-    JavaError.prototype = Object.create(Error.prototype, {
+    JavaError.prototype = teavm_globals.Object.create(teavm_globals.Error.prototype, {
         constructor: {
             configurable: true,
             writable: true,
@@ -710,11 +712,13 @@ if (typeof Reflect === 'object') {
         }
     });
 } else {
-    JavaError = Error;
+    JavaError = teavm_globals.Error;
 }
 
 function $rt_javaException(e) {
-    return e instanceof Error && typeof e[$rt_javaExceptionProp] === 'object' ? e[$rt_javaExceptionProp] : null;
+    return e instanceof teavm_globals.Error && typeof e[$rt_javaExceptionProp] === 'object'
+        ? e[$rt_javaExceptionProp]
+        : null;
 }
 function $rt_jsException(e) {
     return typeof e.$jsException === 'object' ? e.$jsException : null;
@@ -785,7 +789,7 @@ var Long_fromNumber;
 var Long_toNumber;
 var Long_hi;
 var Long_lo;
-if (typeof BigInt !== "function") {
+if (typeof teavm_globals.BigInt !== "function") {
     Long.prototype.toString = function() {
         var result = [];
         var n = this;
@@ -796,7 +800,7 @@ if (typeof BigInt !== "function") {
         var radix = new Long(10, 0);
         do {
             var divRem = Long_divRem(n, radix);
-            result.push(String.fromCharCode(48 + divRem[1].lo));
+            result.push(teavm_globals.String.fromCharCode(48 + divRem[1].lo));
             n = divRem[0];
         } while (n.lo !== 0 || n.hi !== 0);
         result = result.reverse().join('');
@@ -830,28 +834,29 @@ if (typeof BigInt !== "function") {
         return val.lo;
     }
 } else {
-    Long_ZERO = BigInt(0);
+    Long_ZERO = teavm_globals.BigInt(0);
     Long_create = function(lo, hi) {
-        return BigInt.asIntN(64, BigInt.asUintN(64, BigInt(lo))
+        return teavm_globals.BigInt.asIntN(64, teavm_globals.BigInt.asUintN(64, teavm_globals.BigInt(lo))
-            | BigInt.asUintN(64, (BigInt(hi) << BigInt(32))));
+            | teavm_globals.BigInt.asUintN(64, (teavm_globals.BigInt(hi) << teavm_globals.BigInt(32))));
     }
     Long_fromInt = function(val) {
-        return BigInt.asIntN(64, BigInt(val | 0));
+        return teavm_globals.BigInt.asIntN(64, teavm_globals.BigInt(val | 0));
     }
     Long_fromNumber = function(val) {
-        return BigInt.asIntN(64, BigInt(val >= 0 ? Math.floor(val) : Math.ceil(val)));
+        return teavm_globals.BigInt.asIntN(64, teavm_globals.BigInt(
+            val >= 0 ? teavm_globals.Math.floor(val) : teavm_globals.Math.ceil(val)));
     }
     Long_toNumber = function(val) {
-        return Number(val);
+        return teavm_globals.Number(val);
     }
     Long_hi = function(val) {
-        return Number(BigInt.asIntN(64, val >> BigInt(32))) | 0;
+        return teavm_globals.Number(teavm_globals.BigInt.asIntN(64, val >> teavm_globals.BigInt(32))) | 0;
     }
     Long_lo = function(val) {
-        return Number(BigInt.asIntN(32, val)) | 0;
+        return teavm_globals.Number(teavm_globals.BigInt.asIntN(32, val)) | 0;
     }
 }
-var $rt_imul = Math.imul || function(a, b) {
+var $rt_imul = teavm_globals.Math.imul || function(a, b) {
     var ah = (a >>> 16) & 0xFFFF;
     var al = a & 0xFFFF;
     var bh = (b >>> 16) & 0xFFFF;
@@ -902,8 +907,8 @@ function $rt_charArrayToString(array, offset, count) {
     var result = "";
     var limit = offset + count;
     for (var i = offset; i < limit; i = (i + 1024) | 0) {
-        var next = Math.min(limit, (i + 1024) | 0);
+        var next = teavm_globals.Math.min(limit, (i + 1024) | 0);
-        result += String.fromCharCode.apply(null, array.subarray(i, next));
+        result += teavm_globals.String.fromCharCode.apply(null, array.subarray(i, next));
     }
     return result;
 }
@@ -916,7 +921,7 @@ function $rt_stringToCharArray(string, begin, dst, dstBegin, count) {
     }
 }
 function $rt_fastStringToCharArray(string) {
-    var array = new Uint16Array(string.length);
+    var array = new teavm_globals.Uint16Array(string.length);
     for (var i = 0; i < array.length; ++i) {
         array[i] = string.charCodeAt(i);
     }

core/src/main/resources/org/teavm/backend/javascript/simpleThread.js

@@ -24,7 +24,7 @@ function $rt_startThread(runner, callback) {
     }
     if (typeof callback !== 'undefined') {
         callback(result);
-    } else if (result instanceof Error) {
+    } else if (result instanceof teavm_globals.Error) {
         throw result;
     }
 }

core/src/main/resources/org/teavm/backend/javascript/thread.js

@@ -46,14 +46,14 @@ TeaVMThread.prototype.suspend = function(callback) {
 };
 TeaVMThread.prototype.start = function(callback) {
     if (this.status !== 3) {
-        throw new Error("Thread already started");
+        throw new teavm_globals.Error("Thread already started");
     }
     if ($rt_currentNativeThread !== null) {
-        throw new Error("Another thread is running");
+        throw new teavm_globals.Error("Another thread is running");
     }
     this.status = 0;
-    this.completeCallback = callback ? callback : function(result) {
+    this.completeCallback = callback ? callback : (result) => {
-        if (result instanceof Error) {
+        if (result instanceof teavm_globals.Error) {
             throw result;
         }
     };
@@ -61,7 +61,7 @@ TeaVMThread.prototype.start = function(callback) {
 };
 TeaVMThread.prototype.resume = function() {
     if ($rt_currentNativeThread !== null) {
-        throw new Error("Another thread is running");
+        throw new teavm_globals.Error("Another thread is running");
     }
     this.status = 2;
     this.run();
@@ -80,9 +80,7 @@ TeaVMThread.prototype.run = function() {
         var self = this;
         var callback = this.suspendCallback;
         this.suspendCallback = null;
-        callback(function() {
+        callback(() => self.resume());
-            self.resume();
-        });
     } else if (this.status === 0) {
         this.completeCallback(result);
     }
@@ -99,7 +97,7 @@ function $rt_resuming() {
 function $rt_suspend(callback) {
     var nativeThread = $rt_nativeThread();
     if (nativeThread === null) {
-        throw new Error("Suspension point reached from non-threading context (perhaps, from native JS method).");
+        throw new teavm_globals.Error("Suspension point reached from non-threading context (perhaps, from native JS method).");
     }
     return nativeThread.suspend(callback);
 }
@@ -111,5 +109,5 @@ function $rt_nativeThread() {
     return $rt_currentNativeThread;
 }
 function $rt_invalidPointer() {
-    throw new Error("Invalid recorded state");
+    throw new teavm_globals.Error("Invalid recorded state");
 }

jso/impl/src/main/java/org/teavm/jso/impl/JSExceptionsGenerator.java

@@ -25,12 +25,12 @@ public class JSExceptionsGenerator implements Injector {
     public void generate(InjectorContext context, MethodReference methodRef) throws IOException {
         switch (methodRef.getName()) {
             case "getJavaException":
-                context.getWriter().append("$rt_javaException(");
+                context.getWriter().appendFunction("$rt_javaException").append("(");
                 context.writeExpr(context.getArgument(0));
                 context.getWriter().append(")");
                 break;
             case "getJSException":
-                context.getWriter().append("$rt_jsException(");
+                context.getWriter().appendFunction("$rt_jsException").append("(");
                 context.writeExpr(context.getArgument(0));
                 context.getWriter().append(")");
                 break;

jso/impl/src/main/java/org/teavm/jso/impl/JSWrapperGenerator.java

@@ -44,7 +44,7 @@ public class JSWrapperGenerator implements Injector, DependencyPlugin {
                     context.getWriter().append("(");
                 }
                 context.writeExpr(context.getArgument(0));
-                context.getWriter().append(" instanceof ").append("$rt_objcls").append("()");
+                context.getWriter().append(" instanceof ").appendFunction("$rt_objcls").append("()");
                 if (context.getPrecedence().ordinal() >= Precedence.COMPARISON.ordinal()) {
                     context.getWriter().append(")");
                 }

platform/src/main/java/org/teavm/platform/plugin/AsyncMethodGenerator.java

@@ -21,6 +21,8 @@ import org.teavm.backend.javascript.spi.Generator;
 import org.teavm.backend.javascript.spi.GeneratorContext;
 import org.teavm.backend.javascript.spi.VirtualMethodContributor;
 import org.teavm.backend.javascript.spi.VirtualMethodContributorContext;
+import org.teavm.backend.javascript.templating.JavaScriptTemplate;
+import org.teavm.backend.javascript.templating.JavaScriptTemplateFactory;
 import org.teavm.dependency.DependencyAgent;
 import org.teavm.dependency.DependencyPlugin;
 import org.teavm.dependency.MethodDependency;
@@ -36,53 +38,30 @@ import org.teavm.model.ValueType;
 public class AsyncMethodGenerator implements Generator, DependencyPlugin, VirtualMethodContributor {
     private static final MethodDescriptor completeMethod = new MethodDescriptor("complete", Object.class, void.class);
     private static final MethodDescriptor errorMethod = new MethodDescriptor("error", Throwable.class, void.class);
+    private JavaScriptTemplate template;
 
     @Override
     public void generate(GeneratorContext context, SourceWriter writer, MethodReference methodRef) throws IOException {
-        MethodReference asyncRef = getAsyncReference(context.getClassSource(), methodRef);
+        if (template == null) {
-        writer.append("var thread").ws().append('=').ws().append("$rt_nativeThread();").softNewLine();
+            var templateFactory = new JavaScriptTemplateFactory(context.getClassLoader(), context.getClassSource());
-        writer.append("var javaThread").ws().append('=').ws().append("$rt_getThread();").softNewLine();
+            template = templateFactory.createFromResource("org/teavm/platform/plugin/Async.js");
-        writer.append("if").ws().append("(thread.isResuming())").ws().append("{").indent().softNewLine();
-        writer.append("thread.status").ws().append("=").ws().append("0;").softNewLine();
-        writer.append("var result").ws().append("=").ws().append("thread.attribute;").softNewLine();
-        writer.append("if").ws().append("(result instanceof Error)").ws().append("{").indent().softNewLine();
-        writer.append("throw result;").softNewLine();
-        writer.outdent().append("}").softNewLine();
-        writer.append("return result;").softNewLine();
-        writer.outdent().append("}").softNewLine();
-
-        writer.append("var callback").ws().append("=").ws().append("function()").ws().append("{};").softNewLine();
-        writer.append("callback.").appendMethod(completeMethod).ws().append("=").ws()
-                .append("function(val)").ws().append("{").indent().softNewLine();
-        writer.append("thread.attribute").ws().append('=').ws().append("val;").softNewLine();
-        writer.append("$rt_setThread(javaThread);").softNewLine();
-        writer.append("thread.resume();").softNewLine();
-        writer.outdent().append("};").softNewLine();
-        writer.append("callback.").appendMethod(errorMethod).ws().append("=").ws()
-                .append("function(e)").ws().append("{").indent().softNewLine();
-        writer.append("thread.attribute").ws().append('=').ws().append("$rt_exception(e);").softNewLine();
-        writer.append("$rt_setThread(javaThread);").softNewLine();
-        writer.append("thread.resume();").softNewLine();
-        writer.outdent().append("};").softNewLine();
-        writer.append("callback").ws().append("=").ws().appendMethodBody(AsyncCallbackWrapper.class, "create",
-                AsyncCallback.class, AsyncCallbackWrapper.class).append("(callback);").softNewLine();
-        writer.append("thread.suspend(function()").ws().append("{").indent().softNewLine();
-        writer.append("try").ws().append("{").indent().softNewLine();
-        writer.appendMethodBody(asyncRef).append('(');
-        ClassReader cls = context.getClassSource().get(methodRef.getClassName());
-        MethodReader method = cls.getMethod(methodRef.getDescriptor());
-        int start = method.hasModifier(ElementModifier.STATIC) ? 1 : 0;
-        for (int i = start; i <= methodRef.parameterCount(); ++i) {
-            writer.append(context.getParameterName(i));
-            writer.append(',').ws();
         }
-        writer.append("callback);").softNewLine();
+        MethodReference asyncRef = getAsyncReference(context.getClassSource(), methodRef);
-        writer.outdent().append("}").ws().append("catch($e)").ws().append("{").indent().softNewLine();
+        template.builder("asyncMethod")
-        writer.append("callback.").appendMethod(errorMethod).append("($rt_exception($e));")
+                .withContext(context)
-                .softNewLine();
+                .withFragment("callMethod", (w, p) -> {
-        writer.outdent().append("}").softNewLine();
+                    w.appendMethodBody(asyncRef).append('(');
-        writer.outdent().append("});").softNewLine();
+                    ClassReader cls = context.getClassSource().get(methodRef.getClassName());
-        writer.append("return null;").softNewLine();
+                    MethodReader method = cls.getMethod(methodRef.getDescriptor());
+                    int start = method.hasModifier(ElementModifier.STATIC) ? 1 : 0;
+                    for (int i = start; i <= methodRef.parameterCount(); ++i) {
+                        w.append(context.getParameterName(i));
+                        w.append(',').ws();
+                    }
+                    w.append("callback);").softNewLine();
+                })
+                .build()
+                .write(writer, 0);
     }
 
     private MethodReference getAsyncReference(ClassReaderSource classSource, MethodReference methodRef) {

platform/src/main/java/org/teavm/platform/plugin/PlatformGenerator.java

@@ -22,6 +22,8 @@ import org.teavm.backend.javascript.spi.Generator;
 import org.teavm.backend.javascript.spi.GeneratorContext;
 import org.teavm.backend.javascript.spi.Injector;
 import org.teavm.backend.javascript.spi.InjectorContext;
+import org.teavm.backend.javascript.templating.JavaScriptTemplate;
+import org.teavm.backend.javascript.templating.JavaScriptTemplateFactory;
 import org.teavm.dependency.DependencyAgent;
 import org.teavm.dependency.DependencyPlugin;
 import org.teavm.dependency.MethodDependency;
@@ -36,6 +38,8 @@ import org.teavm.platform.PlatformClass;
 import org.teavm.platform.PlatformRunnable;
 
 public class PlatformGenerator implements Generator, Injector, DependencyPlugin {
+    private JavaScriptTemplate template;
+
     @Override
     public void methodReached(DependencyAgent agent, MethodDependency method) {
         switch (method.getReference().getName()) {
@@ -90,37 +94,37 @@ public class PlatformGenerator implements Generator, Injector, DependencyPlugin
     @Override
     public void generate(GeneratorContext context, SourceWriter writer, MethodReference methodRef) throws IOException {
         switch (methodRef.getName()) {
-            case "newInstanceImpl":
-                generateNewInstance(context, writer);
-                break;
             case "prepareNewInstance":
                 generatePrepareNewInstance(context, writer);
                 break;
             case "lookupClass":
                 generateLookup(context, writer);
                 break;
-            case "clone":
-                generateClone(context, writer);
-                break;
-            case "startThread":
-                generateSchedule(context, writer, false);
-                break;
-            case "schedule":
-                generateSchedule(context, writer, true);
-                break;
             case "getEnumConstants":
                 generateEnumConstants(context, writer);
                 break;
             case "getAnnotations":
                 generateAnnotations(context, writer);
                 break;
+            default:
+                generateWithTemplate(context, writer, methodRef);
+                break;
         }
     }
 
+    private void generateWithTemplate(GeneratorContext context, SourceWriter writer, MethodReference methodRef)
+            throws IOException {
+        if (template == null) {
+            template = new JavaScriptTemplateFactory(context.getClassLoader(), context.getClassSource())
+                    .createFromResource("org/teavm/platform/plugin/Platform.js");
+        }
+        template.builder(methodRef.getName()).withContext(context).build().write(writer, 0);
+    }
+
     private void generatePrepareNewInstance(GeneratorContext context, SourceWriter writer) throws IOException {
         MethodDependencyInfo newInstanceMethod = context.getDependency().getMethod(
                 new MethodReference(Platform.class, "newInstanceImpl", PlatformClass.class, Object.class));
-        writer.append("var c").ws().append("=").ws().append("'$$constructor$$';").softNewLine();
+        writer.append("let c").ws().append("=").ws().append("'$$constructor$$';").softNewLine();
         if (newInstanceMethod != null) {
             for (String clsName : newInstanceMethod.getResult().getTypes()) {
                 ClassReader cls = context.getClassSource().get(clsName);
@@ -136,71 +140,21 @@ public class PlatformGenerator implements Generator, Injector, DependencyPlugin
         }
     }
 
-    private void generateNewInstance(GeneratorContext context, SourceWriter writer) throws IOException {
-        String cls = context.getParameterName(1);
-
-        writer.append("if").ws().append("($rt_resuming())").ws().append("{").indent().softNewLine();
-        writer.append("var $r = $rt_nativeThread().pop();").softNewLine();
-        writer.append(cls + ".$$constructor$$($r);").softNewLine();
-        writer.append("if").ws().append("($rt_suspending())").ws().append("{").indent().softNewLine();
-        writer.append("return $rt_nativeThread().push($r);").softNewLine();
-        writer.outdent().append("}").softNewLine();
-        writer.append("return $r;").softNewLine();
-        writer.outdent().append("}").softNewLine();
-
-        writer.append("if").ws().append("(!").append(cls).append(".hasOwnProperty('$$constructor$$'))")
-                .ws().append("{").indent().softNewLine();
-        writer.append("return null;").softNewLine();
-        writer.outdent().append("}").softNewLine();
-
-        writer.append("var $r").ws().append('=').ws().append("new ").append(cls).append("();").softNewLine();
-        writer.append(cls).append(".$$constructor$$($r);").softNewLine();
-        writer.append("if").ws().append("($rt_suspending())").ws().append("{").indent().softNewLine();
-        writer.append("return $rt_nativeThread().push($r);").softNewLine();
-        writer.outdent().append("}").softNewLine();
-        writer.append("return $r;").softNewLine();
-    }
-
     private void generateLookup(GeneratorContext context, SourceWriter writer) throws IOException {
         String param = context.getParameterName(1);
-        writer.append("switch ($rt_ustr(" + param + ")) {").softNewLine().indent();
+        writer.append("switch").ws().append("(").appendFunction("$rt_ustr").append("(" + param + "))")
+                .ws().append("{").softNewLine().indent();
         for (String name : context.getClassSource().getClassNames()) {
-            writer.append("case \"" + name + "\": ").appendClass(name).append(".$clinit(); ")
+            writer.append("case \"" + name + "\":").ws().appendClass(name).append(".$clinit();").ws()
                     .append("return ").appendClass(name).append(";").softNewLine();
         }
-        writer.append("default: return null;").softNewLine();
+        writer.append("default:").ws().append("return null;").softNewLine();
         writer.outdent().append("}").softNewLine();
     }
 
-    private void generateClone(GeneratorContext context, SourceWriter writer) throws IOException {
-        String obj = context.getParameterName(1);
-        writer.append("var copy").ws().append("=").ws().append("new ").append(obj).append(".constructor();")
-                .softNewLine();
-        writer.append("for").ws().append("(var field in " + obj + ")").ws().append("{").softNewLine().indent();
-        writer.append("if").ws().append("(!" + obj + ".hasOwnProperty(field))").ws().append("{").softNewLine().indent();
-        writer.append("continue;").softNewLine().outdent().append("}").softNewLine();
-        writer.append("copy[field]").ws().append("=").ws().append(obj).append("[field];")
-                .softNewLine().outdent().append("}").softNewLine();
-        writer.append("return copy;").softNewLine();
-    }
-
-    private void generateSchedule(GeneratorContext context, SourceWriter writer, boolean timeout) throws IOException {
-        MethodReference launchRef = new MethodReference(Platform.class, "launchThread",
-                PlatformRunnable.class, void.class);
-        String runnable = context.getParameterName(1);
-        writer.append("return setTimeout(function()").ws().append("{").indent().softNewLine();
-        if (timeout) {
-            writer.appendMethodBody(launchRef);
-        } else {
-            writer.append("$rt_threadStarter(").appendMethodBody(launchRef).append(")");
-        }
-        writer.append("(").append(runnable).append(");").softNewLine();
-        writer.outdent().append("},").ws().append(timeout ? context.getParameterName(2) : "0")
-                .append(");").softNewLine();
-    }
 
     private void generateEnumConstants(GeneratorContext context, SourceWriter writer) throws IOException {
-        writer.append("var c").ws().append("=").ws().append("'$$enumConstants$$';").softNewLine();
+        writer.append("let c").ws().append("=").ws().append("'$$enumConstants$$';").softNewLine();
         for (String clsName : context.getClassSource().getClassNames()) {
             ClassReader cls = context.getClassSource().get(clsName);
             MethodReader method = cls.getMethod(new MethodDescriptor("values",
@@ -214,8 +168,8 @@ public class PlatformGenerator implements Generator, Injector, DependencyPlugin
 
         MethodReference selfRef = new MethodReference(Platform.class, "getEnumConstants",
                 PlatformClass.class, Enum[].class);
-        writer.appendMethodBody(selfRef).ws().append("=").ws().append("function(cls)").ws().append("{").softNewLine()
+        writer.appendMethodBody(selfRef).ws().append("=").ws().append("cls").ws().append("=>").ws()
-                .indent();
+                .append("{").softNewLine().indent();
         writer.append("if").ws().append("(!cls.hasOwnProperty(c))").ws().append("{").indent().softNewLine();
         writer.append("return null;").softNewLine();
         writer.outdent().append("}").softNewLine();
@@ -231,7 +185,7 @@ public class PlatformGenerator implements Generator, Injector, DependencyPlugin
     }
 
     private void generateAnnotations(GeneratorContext context, SourceWriter writer) throws IOException {
-        writer.append("var c").ws().append("=").ws().append("'$$annotations$$';").softNewLine();
+        writer.append("let c").ws().append("=").ws().append("'$$annotations$$';").softNewLine();
         for (String clsName : context.getClassSource().getClassNames()) {
             ClassReader annotCls = context.getClassSource().get(clsName + "$$__annotations__$$");
             if (annotCls != null) {
@@ -244,8 +198,8 @@ public class PlatformGenerator implements Generator, Injector, DependencyPlugin
 
         MethodReference selfRef = new MethodReference(Platform.class, "getAnnotations", PlatformClass.class,
                 Annotation[].class);
-        writer.appendMethodBody(selfRef).ws().append("=").ws().append("function(cls)").ws().append("{").softNewLine()
+        writer.appendMethodBody(selfRef).ws().append("=").ws().append("cls").ws().append("=>").ws()
-                .indent();
+                .append("{").softNewLine().indent();
         writer.append("if").ws().append("(!cls.hasOwnProperty(c))").ws().append("{").indent().softNewLine();
         writer.append("return null;").softNewLine();
         writer.outdent().append("}").softNewLine();

platform/src/main/java/org/teavm/platform/plugin/ResourceAccessorGenerator.java

@@ -24,8 +24,9 @@ import org.teavm.model.MethodReference;
 class ResourceAccessorGenerator implements Generator {
     @Override
     public void generate(GeneratorContext context, SourceWriter writer, MethodReference methodRef) throws IOException {
-        writer.append("var result = [];").softNewLine();
+        writer.append("let result").ws().append("=").ws().append("[];").softNewLine();
-        writer.append("for (var key in ").append(context.getParameterName(1)).append(") {").indent().softNewLine();
+        writer.append("for").ws().append("(let key in ").append(context.getParameterName(1)).append(")").ws()
+                .append("{").indent().softNewLine();
         writer.append("result.push(key);").softNewLine();
         writer.outdent().append("}").softNewLine();
         writer.append("return result;").softNewLine();

platform/src/main/java/org/teavm/platform/plugin/ResourceAccessorInjector.java

@@ -95,7 +95,7 @@ class ResourceAccessorInjector implements Injector {
                 context.getWriter().append('(');
                 context.writeExpr(context.getArgument(0));
                 context.getWriter().ws().append("!==").ws().append("null").ws().append("?").ws();
-                context.getWriter().append("$rt_ustr(");
+                context.getWriter().appendFunction("$rt_ustr").append("(");
                 context.writeExpr(context.getArgument(0));
                 context.getWriter().append(")").ws().append(':').ws().append("null)");
                 break;
@@ -114,7 +114,7 @@ class ResourceAccessorInjector implements Injector {
                 return;
             }
         }
-        context.getWriter().append("[$rt_ustr(");
+        context.getWriter().append("[").appendFunction("$rt_ustr").append("(");
         context.writeExpr(property);
         context.getWriter().append(")]");
     }
@@ -127,7 +127,7 @@ class ResourceAccessorInjector implements Injector {
             context.getWriter().append('"');
             return;
         }
-        context.getWriter().append("$rt_ustr(");
+        context.getWriter().appendFunction("$rt_ustr").append("(");
         context.writeExpr(expr);
         context.getWriter().append(")");
     }

platform/src/main/resources/org/teavm/platform/plugin/Async.js

@@ -0,0 +1,50 @@
+/*
+ *  Copyright 2023 Alexey Andreev.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+function asyncMethod() {
+    let thread = $rt_nativeThread();
+    let javaThread = $rt_getThread();
+    if (thread.isResuming()) {
+        thread.status = 0;
+        let result = thread.attribute;
+        if (result instanceof teavm_globals.Error) {
+            throw result;
+        }
+        return result;
+    }
+
+    let callback = function() {};
+    callback[teavm_javaVirtualMethod("complete(Ljava/lang/Object;)V")] = val => {
+        thread.attribute = val;
+        $rt_setThread(javaThread);
+        thread.resume();
+    }
+    callback[teavm_javaVirtualMethod("error(Ljava/lang/Throwable;)V")] = e => {
+        thread.attribute = $rt_exception(e);
+        $rt_setThread(javaThread);
+        thread.resume();
+    }
+    callback = teavm_javaMethod("org.teavm.platform.plugin.AsyncCallbackWrapper",
+        "create(Lorg/teavm/interop/AsyncCallback;)Lorg/teavm/platform/plugin/AsyncCallbackWrapper;")(callback);
+    thread.suspend(() => {
+       try {
+           teavm_fragment("callMethod");
+       } catch ($e) {
+           callback[teavm_javaVirtualMethod("error(Ljava/lang/Throwable;)V")]($e);
+       }
+    });
+    return null;
+}

platform/src/main/resources/org/teavm/platform/plugin/Platform.js

@@ -0,0 +1,62 @@
+/*
+ *  Copyright 2023 Alexey Andreev.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+function newInstanceImpl(cls) {
+    let thread = $rt_nativeThread();
+    if ($rt_resuming()) {
+        let r = thread.pop();
+        cls.$$constructor$$(r);
+        if ($rt_suspending()) {
+            return thread.push(r);
+        }
+        return r;
+    }
+
+    if (!cls.hasOwnProperty("$$constructor$$")) {
+        return null;
+    }
+
+    let r = new cls();
+    cls.$$constructor$$(r);
+    if ($rt_suspending()) {
+        thread.push(r);
+    }
+    return r;
+}
+
+function clone(obj) {
+    let copy = new obj.constructor();
+    for (let field in obj) {
+        if (obj.hasOwnProperty(field)) {
+            copy[field] = obj[field];
+        }
+    }
+    return copy;
+}
+
+function startThread(runnable) {
+    teavm_globals.setTimeout(() => {
+        $rt_threadStarter(teavm_javaMethod("org.teavm.platform.Platform",
+            "launchThread(Lorg/teavm/platform/PlatformRunnable;)V"))(runnable);
+    }, 0);
+}
+
+function schedule(runnable, timeout) {
+    teavm_globals.setTimeout(() => {
+        teavm_javaMethod("org.teavm.platform.Platform",
+                "launchThread(Lorg/teavm/platform/PlatformRunnable;)V")(runnable);
+    }, timeout);
+}

tools/junit/src/main/java/org/teavm/junit/TestExceptionPlugin.java

@@ -65,8 +65,8 @@ class TestExceptionPlugin implements TeaVMPlugin {
     private void renderExceptionMessage(SourceWriter writer) throws IOException {
         writer.appendClass("java.lang.Throwable").append(".prototype.getMessage").ws().append("=").ws()
                 .append("function()").ws().append("{").indent().softNewLine();
-        writer.append("return $rt_ustr(this.").appendMethod("getMessage", String.class).append("());")
+        writer.append("return ").appendFunction("$rt_ustr").append("(this.")
-                .softNewLine();
+                .appendMethod("getMessage", String.class).append("());").softNewLine();
         writer.outdent().append("};").newLine();
     }
 }