Annotation converters as a separate BaseRenderer property

HT154 · HT154 · commit 274ba33f07a8 · 2025-11-29T12:57:31.000-08:00
diff --git a/pkl-core/src/main/java/org/pkl/core/runtime/Identifier.java b/pkl-core/src/main/java/org/pkl/core/runtime/Identifier.java
@@ -62,6 +62,7 @@ public final class Identifier implements Comparable<Identifier> {
   public static final Identifier ROOT_ELEMENT_NAME = get("rootElementName");
   public static final Identifier ROOT_ELEMENT_ATTRIBUTES = get("rootElementAttributes");
   public static final Identifier CONVERTERS = get("converters");
+  public static final Identifier ANNOTATION_CONVERTERS = get("annotationConverters");
   public static final Identifier USE_MAPPING = get("useMapping");
 
   // members of pkl.base#RegexMatch
diff --git a/pkl-core/src/main/java/org/pkl/core/runtime/TestRunner.java b/pkl-core/src/main/java/org/pkl/core/runtime/TestRunner.java
@@ -1,5 +1,5 @@
 /*
- * Copyright © 2024 Apple Inc. and the Pkl project authors. All rights reserved.
+ * Copyright © 2024-2025 Apple Inc. and the Pkl project authors. All rights reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -42,7 +42,7 @@
 
 /** Runs test results examples and facts. */
 public final class TestRunner {
-  private static final PklConverter converter = new PklConverter(VmMapping.empty());
+  private static final PklConverter converter = PklConverter.NOOP;
   private final BufferedLogger logger;
   private final StackFrameTransformer stackFrameTransformer;
   private final boolean overwrite;
diff --git a/pkl-core/src/main/java/org/pkl/core/runtime/VmPklBinaryEncoder.java b/pkl-core/src/main/java/org/pkl/core/runtime/VmPklBinaryEncoder.java
@@ -38,7 +38,7 @@ public VmPklBinaryEncoder(MessageBufferPacker packer, PklConverter converter) {
   }
 
   public VmPklBinaryEncoder(MessageBufferPacker packer) {
-    this(packer, new PklConverter(VmMapping.empty()));
+    this(packer, PklConverter.NOOP);
   }
 
   private void packCode(PklBinaryCode code) throws IOException {
diff --git a/pkl-core/src/main/java/org/pkl/core/stdlib/PklConverter.java b/pkl-core/src/main/java/org/pkl/core/stdlib/PklConverter.java
@@ -46,12 +46,13 @@ public final class PklConverter implements VmValueConverter<Object> {
   private final @Nullable VmFunction classConverter;
   private final @Nullable VmFunction typeAliasConverter;
 
-  public PklConverter(VmMapping converters) {
+  public PklConverter(VmMapping converters, VmMapping annotationConverters) {
     // As of 0.18, `converters` is forced by the mapping type check,
     // but let's not rely on this implementation detail.
     converters.force(false, false);
+    annotationConverters.force(false, false);
     typeConverters = createTypeConverters(converters);
-    annotationConverters = createAnnotationConverters(converters);
+    this.annotationConverters = createAnnotationConverters(annotationConverters);
     pathConverters = createPathConverters(converters);
 
     stringConverter = typeConverters.get(BaseModule.getStringClass());
@@ -75,6 +76,20 @@ public PklConverter(VmMapping converters) {
     typeAliasConverter = typeConverters.get(BaseModule.getTypeAliasClass());
   }
 
+  public static final PklConverter NOOP = new PklConverter(VmMapping.empty(), VmMapping.empty());
+
+  public static PklConverter fromRenderer(VmTyped renderer) {
+    var converters = (VmMapping) VmUtils.readMember(renderer, Identifier.CONVERTERS);
+    var annotationConverters =
+        (VmMapping) VmUtils.readMember(renderer, Identifier.ANNOTATION_CONVERTERS);
+    return new PklConverter(converters, annotationConverters);
+  }
+
+  public static PklConverter fromParser(VmTyped parser) {
+    var converters = (VmMapping) VmUtils.readMember(parser, Identifier.CONVERTERS);
+    return new PklConverter(converters, VmMapping.empty()); // no annotation converters in parsers
+  }
+
   @Override
   public Object convertString(String value, Iterable<Object> path) {
     return doConvert(value, path, stringConverter);
@@ -203,33 +218,19 @@ private Map<VmClass, VmFunction> createTypeConverters(VmMapping converters) {
         (key, member, value) -> {
           assert value != null; // forced in ctor
           if (key instanceof VmClass vmClass) {
-            var vmFunction = (VmFunction) value;
-            if (vmClass.isSubclassOf(BaseModule.getAnnotationClass())
-                && vmFunction.getParameterCount() > 1) {
-              // when the class is a subclass of Annotation and the function doesn't have 1 param
-              // this goes in annotationConverters instead
-              return true;
-            }
-            result.put(vmClass, vmFunction);
+            result.put(vmClass, (VmFunction) value);
           }
           return true;
         });
     return result;
   }
 
-  private Map<VmClass, VmFunction> createAnnotationConverters(VmMapping converters) {
+  private Map<VmClass, VmFunction> createAnnotationConverters(VmMapping annotationConverters) {
     var result = new HashMap<VmClass, VmFunction>();
-    converters.iterateMemberValues(
+    annotationConverters.iterateMemberValues(
         (key, member, value) -> {
           assert value != null; // forced in ctor
-          if (key instanceof VmClass vmClass
-              && vmClass.isSubclassOf(BaseModule.getAnnotationClass())) {
-            var vmFunction = (VmFunction) value;
-            if (vmFunction.getParameterCount() != 3) {
-              return true;
-            }
-            result.put(vmClass, vmFunction);
-          }
+          result.put((VmClass) key, (VmFunction) value);
           return true;
         });
     return result;
diff --git a/pkl-core/src/main/java/org/pkl/core/stdlib/base/JsonRendererNodes.java b/pkl-core/src/main/java/org/pkl/core/stdlib/base/JsonRendererNodes.java
@@ -52,9 +52,7 @@ protected String eval(VmTyped self, Object value) {
   private static JsonRenderer createRenderer(VmTyped self, StringBuilder builder) {
     var indent = (String) VmUtils.readMember(self, Identifier.INDENT);
     var omitNullProperties = (boolean) VmUtils.readMember(self, Identifier.OMIT_NULL_PROPERTIES);
-    var converters = (VmMapping) VmUtils.readMember(self, Identifier.CONVERTERS);
-    var converter = new PklConverter(converters);
-    return new JsonRenderer(builder, indent, converter, omitNullProperties);
+    return new JsonRenderer(builder, indent, PklConverter.fromRenderer(self), omitNullProperties);
   }
 
   private static final class JsonRenderer extends AbstractStringRenderer {
diff --git a/pkl-core/src/main/java/org/pkl/core/stdlib/base/PListRendererNodes.java b/pkl-core/src/main/java/org/pkl/core/stdlib/base/PListRendererNodes.java
@@ -48,9 +48,7 @@ protected String eval(VmTyped self, Object value) {
 
   private static PListRenderer createRenderer(VmTyped self, StringBuilder builder) {
     var indent = (String) VmUtils.readMember(self, Identifier.INDENT);
-    var converters = (VmMapping) VmUtils.readMember(self, Identifier.CONVERTERS);
-    var converter = new PklConverter(converters);
-    return new PListRenderer(builder, indent, converter);
+    return new PListRenderer(builder, indent, PklConverter.fromRenderer(self));
   }
 
   // keep in sync with org.pkl.core.PListRenderer
diff --git a/pkl-core/src/main/java/org/pkl/core/stdlib/base/PcfRendererNodes.java b/pkl-core/src/main/java/org/pkl/core/stdlib/base/PcfRendererNodes.java
@@ -1,5 +1,5 @@
 /*
- * Copyright © 2024 Apple Inc. and the Pkl project authors. All rights reserved.
+ * Copyright © 2024-2025 Apple Inc. and the Pkl project authors. All rights reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -46,12 +46,14 @@ protected String eval(VmTyped self, Object value) {
 
   private static PcfRenderer createRenderer(VmTyped self, StringBuilder builder) {
     var indent = (String) VmUtils.readMember(self, Identifier.INDENT);
-    var converters = (VmMapping) VmUtils.readMember(self, Identifier.CONVERTERS);
     var omitNullProperties = (boolean) VmUtils.readMember(self, Identifier.OMIT_NULL_PROPERTIES);
     var useCustomStringDelimiters =
         (boolean) VmUtils.readMember(self, Identifier.USE_CUSTOM_STRING_DELIMITERS);
-    var converter = new PklConverter(converters);
     return new PcfRenderer(
-        builder, indent, converter, omitNullProperties, useCustomStringDelimiters);
+        builder,
+        indent,
+        PklConverter.fromRenderer(self),
+        omitNullProperties,
+        useCustomStringDelimiters);
   }
 }
diff --git a/pkl-core/src/main/java/org/pkl/core/stdlib/base/PropertiesRendererNodes.java b/pkl-core/src/main/java/org/pkl/core/stdlib/base/PropertiesRendererNodes.java
@@ -69,9 +69,8 @@ protected String eval(VmTyped self, Object value) {
   private static PropertiesRenderer createRenderer(VmTyped self, StringBuilder builder) {
     var omitNullProperties = (boolean) VmUtils.readMember(self, Identifier.OMIT_NULL_PROPERTIES);
     var restrictCharset = (boolean) VmUtils.readMember(self, Identifier.RESTRICT_CHARSET);
-    var converters = (VmMapping) VmUtils.readMember(self, Identifier.CONVERTERS);
-    var PklConverter = new PklConverter(converters);
-    return new PropertiesRenderer(builder, omitNullProperties, restrictCharset, PklConverter);
+    return new PropertiesRenderer(
+        builder, omitNullProperties, restrictCharset, PklConverter.fromRenderer(self));
   }
 
   private static final class PropertiesRenderer extends AbstractStringRenderer {
diff --git a/pkl-core/src/main/java/org/pkl/core/stdlib/base/YamlRendererNodes.java b/pkl-core/src/main/java/org/pkl/core/stdlib/base/YamlRendererNodes.java
@@ -69,10 +69,13 @@ private static YamlRenderer createRenderer(VmTyped self, StringBuilder builder)
     var indentWidth = ((Long) VmUtils.readMember(self, Identifier.INDENT_WIDTH)).intValue();
     var omitNullProperties = (boolean) VmUtils.readMember(self, Identifier.OMIT_NULL_PROPERTIES);
     var isStream = (boolean) VmUtils.readMember(self, Identifier.IS_STREAM);
-    var converters = (VmMapping) VmUtils.readMember(self, Identifier.CONVERTERS);
-    var converter = new PklConverter(converters);
     return new YamlRenderer(
-        builder, " ".repeat(indentWidth), converter, omitNullProperties, mode, isStream);
+        builder,
+        " ".repeat(indentWidth),
+        PklConverter.fromRenderer(self),
+        omitNullProperties,
+        mode,
+        isStream);
   }
 
   private static final class YamlRenderer extends AbstractStringRenderer {
diff --git a/pkl-core/src/main/java/org/pkl/core/stdlib/json/ParserNodes.java b/pkl-core/src/main/java/org/pkl/core/stdlib/json/ParserNodes.java
@@ -1,5 +1,5 @@
 /*
- * Copyright © 2024 Apple Inc. and the Pkl project authors. All rights reserved.
+ * Copyright © 2024-2025 Apple Inc. and the Pkl project authors. All rights reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -51,7 +51,7 @@ protected Object eval(
     }
 
     private Object doParse(VmTyped self, String text) {
-      var converter = createConverter(self);
+      var converter = PklConverter.fromParser(self);
       var useMapping = (boolean) VmUtils.readMember(self, Identifier.USE_MAPPING);
       var handler = new Handler(converter, useMapping);
       var parser = new JsonParser(handler);
@@ -64,11 +64,6 @@ private Object doParse(VmTyped self, String text) {
     }
   }
 
-  private static PklConverter createConverter(VmTyped self) {
-    var converters = (VmMapping) VmUtils.readMember(self, Identifier.CONVERTERS);
-    return new PklConverter(converters);
-  }
-
   private static class Handler
       extends JsonHandler<EconomicMap<Object, ObjectMember>, EconomicMap<Object, ObjectMember>> {
     private final PklConverter converter;
diff --git a/pkl-core/src/main/java/org/pkl/core/stdlib/jsonnet/RendererNodes.java b/pkl-core/src/main/java/org/pkl/core/stdlib/jsonnet/RendererNodes.java
@@ -47,9 +47,7 @@ private static Renderer createRenderer(VmTyped self, StringBuilder builder) {
     var indent = (String) VmNull.unwrap(VmUtils.readMember(self, Identifier.INDENT));
     if (indent == null) indent = "";
     var omitNullProperties = (boolean) VmUtils.readMember(self, Identifier.OMIT_NULL_PROPERTIES);
-    var converters = (VmMapping) VmUtils.readMember(self, Identifier.CONVERTERS);
-    var converter = new PklConverter(converters);
-    return new Renderer(builder, indent, omitNullProperties, converter);
+    return new Renderer(builder, indent, omitNullProperties, PklConverter.fromRenderer(self));
   }
 
   public abstract static class renderDocument extends ExternalMethod1Node {
diff --git a/pkl-core/src/main/java/org/pkl/core/stdlib/pklbinary/RendererNodes.java b/pkl-core/src/main/java/org/pkl/core/stdlib/pklbinary/RendererNodes.java
@@ -19,12 +19,9 @@
 import com.oracle.truffle.api.dsl.Specialization;
 import org.msgpack.core.MessageBufferPacker;
 import org.msgpack.core.MessagePack;
-import org.pkl.core.runtime.Identifier;
 import org.pkl.core.runtime.VmBytes;
-import org.pkl.core.runtime.VmMapping;
 import org.pkl.core.runtime.VmPklBinaryEncoder;
 import org.pkl.core.runtime.VmTyped;
-import org.pkl.core.runtime.VmUtils;
 import org.pkl.core.stdlib.ExternalMethod1Node;
 import org.pkl.core.stdlib.PklConverter;
 import org.pkl.core.util.Nullable;
@@ -64,8 +61,6 @@ protected VmBytes eval(VmTyped self, Object value) {
   }
 
   private static VmPklBinaryEncoder createRenderer(VmTyped self, MessageBufferPacker packer) {
-    var converters = (VmMapping) VmUtils.readMember(self, Identifier.CONVERTERS);
-    var converter = new PklConverter(converters);
-    return new VmPklBinaryEncoder(packer, converter);
+    return new VmPklBinaryEncoder(packer, PklConverter.fromRenderer(self));
   }
 }
diff --git a/pkl-core/src/main/java/org/pkl/core/stdlib/protobuf/RendererNodes.java b/pkl-core/src/main/java/org/pkl/core/stdlib/protobuf/RendererNodes.java
@@ -135,9 +135,8 @@ private static String renderType(Object value) {
   @TruffleBoundary
   private static ProtobufRenderer createRenderer(VmTyped self, StringBuilder builder) {
     var indent = (String) VmUtils.readMember(self, Identifier.INDENT);
-    var converters = (VmMapping) VmUtils.readMember(self, Identifier.CONVERTERS);
 
-    return new ProtobufRenderer(builder, indent, new PklConverter(converters));
+    return new ProtobufRenderer(builder, indent, PklConverter.fromRenderer(self));
   }
 
   private static final class ProtobufRenderer extends AbstractStringRenderer {
diff --git a/pkl-core/src/main/java/org/pkl/core/stdlib/test/report/JUnitReport.java b/pkl-core/src/main/java/org/pkl/core/stdlib/test/report/JUnitReport.java
@@ -239,8 +239,7 @@ private String stripColors(String str) {
 
   private static String renderXML(String indent, String version, VmDynamic value) {
     var builder = new StringBuilder();
-    var converter = new PklConverter(VmMapping.empty());
-    var renderer = new Renderer(builder, indent, version, "", VmMapping.empty(), converter);
+    var renderer = new Renderer(builder, indent, version, "", VmMapping.empty(), PklConverter.NOOP);
     renderer.renderDocument(value);
     return builder.toString();
   }
diff --git a/pkl-core/src/main/java/org/pkl/core/stdlib/xml/RendererNodes.java b/pkl-core/src/main/java/org/pkl/core/stdlib/xml/RendererNodes.java
@@ -34,10 +34,13 @@ private static Renderer createRenderer(VmTyped self, StringBuilder builder) {
     var rootElementName = (String) VmUtils.readMember(self, Identifier.ROOT_ELEMENT_NAME);
     var rootElementAttributes =
         (VmMapping) VmUtils.readMember(self, Identifier.ROOT_ELEMENT_ATTRIBUTES);
-    var converters = (VmMapping) VmUtils.readMember(self, Identifier.CONVERTERS);
-    var converter = new PklConverter(converters);
     return new Renderer(
-        builder, indent, xmlVersion, rootElementName, rootElementAttributes, converter);
+        builder,
+        indent,
+        xmlVersion,
+        rootElementName,
+        rootElementAttributes,
+        PklConverter.fromRenderer(self));
   }
 
   public abstract static class renderDocument extends ExternalMethod1Node {
diff --git a/pkl-core/src/main/java/org/pkl/core/stdlib/yaml/ParserNodes.java b/pkl-core/src/main/java/org/pkl/core/stdlib/yaml/ParserNodes.java
@@ -65,7 +65,7 @@ protected Object eval(
     }
 
     private Object doParse(VmTyped self, String text, String uri) {
-      var converter = createConverter(self);
+      var converter = PklConverter.fromParser(self);
       var load = createLoad(self, text, uri, converter);
 
       try {
@@ -101,7 +101,7 @@ protected Object eval(
     }
 
     private VmList doParseAll(VmTyped self, String text, String uri) {
-      var converter = createConverter(self);
+      var converter = PklConverter.fromParser(self);
       var load = createLoad(self, text, uri, converter);
       var builder = VmList.EMPTY.builder();
 
@@ -123,11 +123,6 @@ private VmList doParseAll(VmTyped self, String text, String uri) {
     }
   }
 
-  private static PklConverter createConverter(VmTyped self) {
-    var converters = (VmMapping) VmUtils.readMember(self, Identifier.CONVERTERS);
-    return new PklConverter(converters);
-  }
-
   private static int getMaxCollectionAliases(VmTyped self) {
     var max = (Long) VmUtils.readMember(self, Identifier.MAX_COLLECTION_ALIASES);
     return max.intValue(); // has Pkl type `Int32(isPositive)`
diff --git a/pkl-core/src/test/files/LanguageSnippetTests/input/api/annotationConverters.pkl b/pkl-core/src/test/files/LanguageSnippetTests/input/api/annotationConverters.pkl
@@ -56,7 +56,7 @@ class Bar extends Foo {
 output {
   value = new Bar {}
   renderer = new PcfRenderer {
-    converters {
+    annotationConverters {
       [NameTransform] = new NameTransform {}.apply
       [CamelCase] = new CamelCase {}.apply
       [MultiplyValue] = new MultiplyValue {}.apply
diff --git a/pkl-core/src/test/files/LanguageSnippetTests/output/api/pklbinary1.msgpack.yaml b/pkl-core/src/test/files/LanguageSnippetTests/output/api/pklbinary1.msgpack.yaml
@@ -172,6 +172,12 @@
           - 
             - 3
             - {}
+        - 
+          - 16
+          - 'annotationConverters'
+          - 
+            - 3
+            - {}
         - 
           - 16
           - 'extension'
diff --git a/stdlib/base.pkl b/stdlib/base.pkl
@@ -348,19 +348,26 @@ abstract class BaseValueRenderer {
   /// For example, paths `server.timeout` and `racks[*].server.timeout`
   /// both match path spec `server.timeout`, whereas path `server.timeout.millis` does not.
   ///
-  /// Annotation converters:
-  /// - When key is [Class] that is subclass of [Annotation] and value has three parameters.
-  /// - Checked for each property of [Typed] values.
-  /// - Allows transforming property names and value.
-  /// - Each of the property annotations of the enclosing class is checked in order: starting with
-  ///   the annotations (in order) of the current class, then repeating up the class hierarchy.
-  /// - Multiple annotation converters can apply; converters for matching annotations are called in
-  ///   order, with the result of one being passed to the next.
-  /// - Annotation converters can overlap with class/path converters and apply first.
-  converters: Mapping<
-    Class | String,
-    ((unknown) -> Any) | (String, unknown, unknown) -> Pair<String, Any>,
-  >
+  converters: Mapping<Class | String, (unknown) -> Any>
+
+  /// Annotation converters to apply before values are rendered.
+  ///
+  /// Annotation converters are checked for each property of rendered [Typed] values.
+  /// If a property has an annotation for which a converter is defined, the converter function is
+  /// called with the property name, the value of the annotation, and the property value. The
+  /// converter function must return a [Pair] of the converted property name and value.
+  ///
+  /// Each of the property annotations of the enclosing class is checked in order, starting with the
+  /// annotations (top to bottom) of the current class, then repeating for each parent class in the
+  /// hierarchy.
+  /// Multiple annotation converters can apply; converters for matching annotations are called in
+  /// order, with the result of one being passed to the next.
+  ///
+  /// At most one converter is applied per annotation. The most specific class (according to class
+  /// hierarchy) wins.
+  ///
+  /// Annotation converters can overlap with [converters] and apply first.
+  annotationConverters: Mapping<Class, (String, unknown, unknown) -> Pair<String, Any>>
 
   /// The file extension associated with this output format,
   /// or [null] if this format does not have an extension.

Original file line number	Diff line number	Diff line change
`@@ -38,7 +38,7 @@ public VmPklBinaryEncoder(MessageBufferPacker packer, PklConverter converter) {`
`38`	`38`	`}`
`39`	`39`
`40`	`40`	`public VmPklBinaryEncoder(MessageBufferPacker packer) {`
`41`		`- this(packer, new PklConverter(VmMapping.empty()));`
	`41`	`+ this(packer, PklConverter.NOOP);`
`42`	`42`	`}`
`43`	`43`
`44`	`44`	`private void packCode(PklBinaryCode code) throws IOException {`
Original file line number	Diff line number	Diff line change
`@@ -48,9 +48,7 @@ protected String eval(VmTyped self, Object value) {`
`48`	`48`
`49`	`49`	`private static PListRenderer createRenderer(VmTyped self, StringBuilder builder) {`
`50`	`50`	`var indent = (String) VmUtils.readMember(self, Identifier.INDENT);`
`51`		`- var converters = (VmMapping) VmUtils.readMember(self, Identifier.CONVERTERS);`
`52`		`- var converter = new PklConverter(converters);`
`53`		`- return new PListRenderer(builder, indent, converter);`
	`51`	`+ return new PListRenderer(builder, indent, PklConverter.fromRenderer(self));`
`54`	`52`	`}`
`55`	`53`
`56`	`54`	`// keep in sync with org.pkl.core.PListRenderer`
Original file line number	Diff line number	Diff line change
`@@ -1,5 +1,5 @@`
`1`	`1`	`/*`
`2`		`- * Copyright © 2024 Apple Inc. and the Pkl project authors. All rights reserved.`
	`2`	`+ * Copyright © 2024-2025 Apple Inc. and the Pkl project authors. All rights reserved.`
`3`	`3`	`*`
`4`	`4`	`* Licensed under the Apache License, Version 2.0 (the "License");`
`5`	`5`	`* you may not use this file except in compliance with the License.`
`@@ -51,7 +51,7 @@ protected Object eval(`
`51`	`51`	`}`
`52`	`52`
`53`	`53`	`private Object doParse(VmTyped self, String text) {`
`54`		`- var converter = createConverter(self);`
	`54`	`+ var converter = PklConverter.fromParser(self);`
`55`	`55`	`var useMapping = (boolean) VmUtils.readMember(self, Identifier.USE_MAPPING);`
`56`	`56`	`var handler = new Handler(converter, useMapping);`
`57`	`57`	`var parser = new JsonParser(handler);`
`@@ -64,11 +64,6 @@ private Object doParse(VmTyped self, String text) {`
`64`	`64`	`}`
`65`	`65`	`}`
`66`	`66`
`67`		`- private static PklConverter createConverter(VmTyped self) {`
`68`		`- var converters = (VmMapping) VmUtils.readMember(self, Identifier.CONVERTERS);`
`69`		`- return new PklConverter(converters);`
`70`		`- }`
`71`		`-`
`72`	`67`	`private static class Handler`
`73`	`68`	`extends JsonHandler<EconomicMap<Object, ObjectMember>, EconomicMap<Object, ObjectMember>> {`
`74`	`69`	`private final PklConverter converter;`