apache · davsclaus · Feb 1, 2026 · Feb 1, 2026
diff --git a/catalog/camel-catalog/src/generated/resources/org/apache/camel/catalog/languages/simple.json b/catalog/camel-catalog/src/generated/resources/org/apache/camel/catalog/languages/simple.json
@@ -128,11 +128,12 @@
     "trim(exp)": { "index": 101, "kind": "function", "displayName": "Trim", "group": "function", "label": "function", "required": false, "javaType": "String", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "The trim function trims the message body (or expression) by removing all leading and trailing white spaces.", "ognl": false, "suffix": "}" },
     "type:name.field": { "index": 102, "kind": "function", "displayName": "Java Field Value", "group": "function", "label": "function", "required": false, "javaType": "Object", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "To refer to a type or field by its classname. To refer to a field, you can append .FIELD_NAME. For example, you can refer to the constant field from Exchange as: `org.apache.camel.Exchange.FILE_NAME`", "ognl": false, "suffix": "}" },
     "kindOfType(exp)": { "index": 103, "kind": "function", "displayName": "Kind of Type", "group": "function", "label": "function", "required": false, "javaType": "Object", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "What kind of type is the value (null,number,string,boolean,array,object)", "ognl": false, "suffix": "}" },
-    "uppercase(exp)": { "index": 104, "kind": "function", "displayName": "Uppercase", "group": "function", "label": "function", "required": false, "javaType": "String", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "Uppercases the message body (or expression)", "ognl": false, "suffix": "}" },
-    "uuid(type)": { "index": 105, "kind": "function", "displayName": "Generate UUID", "group": "function", "label": "function", "required": false, "javaType": "String", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "Returns a UUID using the Camel `UuidGenerator`. You can choose between `default`, `classic`, `short` and `simple` as the type. If no type is given, the default is used. It is also possible to use a custom `UuidGenerator` and bind the bean to the Registry with an id. For example `${uuid(myGenerator)}` where the ID is _myGenerator_.", "ognl": false, "suffix": "}" },
-    "variable.name": { "index": 106, "kind": "function", "displayName": "Variable", "group": "function", "label": "function", "required": false, "javaType": "Object", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "The variable with the given name", "ognl": true, "suffix": "}" },
-    "variableAs(key,type)": { "index": 107, "kind": "function", "displayName": "Variable As", "group": "function", "label": "function", "required": false, "javaType": "Object", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "Converts the variable to the given type (classname).", "ognl": false, "suffix": "}" },
-    "variables": { "index": 108, "kind": "function", "displayName": "Variables", "group": "function", "label": "function", "required": false, "javaType": "java.util.Map", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "Returns all the variables from the current Exchange in a Map", "ognl": false, "suffix": "}" },
-    "xpath(input,exp)": { "index": 109, "kind": "function", "displayName": "XPath", "group": "function", "label": "function", "required": false, "javaType": "Object", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "When working with XML data, then this allows using the XPath language, for example, to extract data from the message body (in XML format). This requires having camel-xpath JAR on the classpath. For input (optional), you can choose `header:key`, `exchangeProperty:key` or `variable:key` to use as input for the XML payload instead of the message body.", "ognl": false, "suffix": "}" }
+    "unquote(exp)": { "index": 104, "kind": "function", "displayName": "Unquote", "group": "function", "label": "function", "required": false, "javaType": "String", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "Returns the message body (or expression) with any leading\/ending quotes removed", "ognl": false, "suffix": "}" },
+    "uppercase(exp)": { "index": 105, "kind": "function", "displayName": "Uppercase", "group": "function", "label": "function", "required": false, "javaType": "String", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "Uppercases the message body (or expression)", "ognl": false, "suffix": "}" },
+    "uuid(type)": { "index": 106, "kind": "function", "displayName": "Generate UUID", "group": "function", "label": "function", "required": false, "javaType": "String", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "Returns a UUID using the Camel `UuidGenerator`. You can choose between `default`, `classic`, `short` and `simple` as the type. If no type is given, the default is used. It is also possible to use a custom `UuidGenerator` and bind the bean to the Registry with an id. For example `${uuid(myGenerator)}` where the ID is _myGenerator_.", "ognl": false, "suffix": "}" },
+    "variable.name": { "index": 107, "kind": "function", "displayName": "Variable", "group": "function", "label": "function", "required": false, "javaType": "Object", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "The variable with the given name", "ognl": true, "suffix": "}" },
+    "variableAs(key,type)": { "index": 108, "kind": "function", "displayName": "Variable As", "group": "function", "label": "function", "required": false, "javaType": "Object", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "Converts the variable to the given type (classname).", "ognl": false, "suffix": "}" },
+    "variables": { "index": 109, "kind": "function", "displayName": "Variables", "group": "function", "label": "function", "required": false, "javaType": "java.util.Map", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "Returns all the variables from the current Exchange in a Map", "ognl": false, "suffix": "}" },
+    "xpath(input,exp)": { "index": 110, "kind": "function", "displayName": "XPath", "group": "function", "label": "function", "required": false, "javaType": "Object", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "When working with XML data, then this allows using the XPath language, for example, to extract data from the message body (in XML format). This requires having camel-xpath JAR on the classpath. For input (optional), you can choose `header:key`, `exchangeProperty:key` or `variable:key` to use as input for the XML payload instead of the message body.", "ognl": false, "suffix": "}" }
   }
 }
diff --git a/...csimple-joor/src/test/java/org/apache/camel/language/csimple/joor/OriginalSimpleTest.java b/...csimple-joor/src/test/java/org/apache/camel/language/csimple/joor/OriginalSimpleTest.java
@@ -2682,6 +2682,27 @@ public void testSafeQuote() {
         assertEquals("\"{A=1, B=2}\"", s);
     }
 
+    @Test
+    public void testUnquote() {
+        exchange.getMessage().setBody("\"Hello World\"");
+
+        Expression expression = context.resolveLanguage("csimple").createExpression("${unquote()}");
+        String s = expression.evaluate(exchange, String.class);
+        assertEquals("Hello World", s);
+
+        expression = context.resolveLanguage("csimple").createExpression("${unquote(${body})}");
+        s = expression.evaluate(exchange, String.class);
+        assertEquals("Hello World", s);
+
+        expression = context.resolveLanguage("csimple").createExpression("${unquote('\"Hi\"')}");
+        s = expression.evaluate(exchange, String.class);
+        assertEquals("Hi", s);
+
+        expression = context.resolveLanguage("csimple").createExpression("${unquote('Hi')}");
+        s = expression.evaluate(exchange, String.class);
+        assertEquals("Hi", s);
+    }
+
     @Test
     public void testTrim() {
         exchange.getMessage().setBody("   Hello World ");

diff --git a/core/camel-api/src/main/java/org/apache/camel/spi/SimpleFunctionRegistry.java b/core/camel-api/src/main/java/org/apache/camel/spi/SimpleFunctionRegistry.java
@@ -16,6 +16,8 @@
  */
 package org.apache.camel.spi;
 
+import java.util.Set;
+
 import org.apache.camel.Expression;
 
 /**
@@ -46,6 +48,11 @@ public interface SimpleFunctionRegistry {
      */
     Expression getFunction(String name);
 
+    /**
+     * Returns a set with all the function names
+     */
+    Set<String> getFunctionNames();
+
     /**
      * Number of custom functions
      */

diff --git a/...base-engine/src/main/java/org/apache/camel/impl/engine/DefaultSimpleFunctionRegistry.java b/...base-engine/src/main/java/org/apache/camel/impl/engine/DefaultSimpleFunctionRegistry.java
@@ -17,6 +17,7 @@
 package org.apache.camel.impl.engine;
 
 import java.util.Map;
+import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
 
 import org.apache.camel.CamelContext;
@@ -53,6 +54,11 @@ public Expression getFunction(String name) {
         return functions.get(name);
     }
 
+    @Override
+    public Set<String> getFunctionNames() {
+        return functions.keySet();
+    }
+
     @Override
     protected void doStop() throws Exception {
         super.doShutdown();

diff --git a/...e-languages/src/generated/resources/META-INF/org/apache/camel/language/simple/simple.json b/...e-languages/src/generated/resources/META-INF/org/apache/camel/language/simple/simple.json
@@ -128,11 +128,12 @@
     "trim(exp)": { "index": 101, "kind": "function", "displayName": "Trim", "group": "function", "label": "function", "required": false, "javaType": "String", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "The trim function trims the message body (or expression) by removing all leading and trailing white spaces.", "ognl": false, "suffix": "}" },
     "type:name.field": { "index": 102, "kind": "function", "displayName": "Java Field Value", "group": "function", "label": "function", "required": false, "javaType": "Object", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "To refer to a type or field by its classname. To refer to a field, you can append .FIELD_NAME. For example, you can refer to the constant field from Exchange as: `org.apache.camel.Exchange.FILE_NAME`", "ognl": false, "suffix": "}" },
     "kindOfType(exp)": { "index": 103, "kind": "function", "displayName": "Kind of Type", "group": "function", "label": "function", "required": false, "javaType": "Object", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "What kind of type is the value (null,number,string,boolean,array,object)", "ognl": false, "suffix": "}" },
-    "uppercase(exp)": { "index": 104, "kind": "function", "displayName": "Uppercase", "group": "function", "label": "function", "required": false, "javaType": "String", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "Uppercases the message body (or expression)", "ognl": false, "suffix": "}" },
-    "uuid(type)": { "index": 105, "kind": "function", "displayName": "Generate UUID", "group": "function", "label": "function", "required": false, "javaType": "String", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "Returns a UUID using the Camel `UuidGenerator`. You can choose between `default`, `classic`, `short` and `simple` as the type. If no type is given, the default is used. It is also possible to use a custom `UuidGenerator` and bind the bean to the Registry with an id. For example `${uuid(myGenerator)}` where the ID is _myGenerator_.", "ognl": false, "suffix": "}" },
-    "variable.name": { "index": 106, "kind": "function", "displayName": "Variable", "group": "function", "label": "function", "required": false, "javaType": "Object", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "The variable with the given name", "ognl": true, "suffix": "}" },
-    "variableAs(key,type)": { "index": 107, "kind": "function", "displayName": "Variable As", "group": "function", "label": "function", "required": false, "javaType": "Object", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "Converts the variable to the given type (classname).", "ognl": false, "suffix": "}" },
-    "variables": { "index": 108, "kind": "function", "displayName": "Variables", "group": "function", "label": "function", "required": false, "javaType": "java.util.Map", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "Returns all the variables from the current Exchange in a Map", "ognl": false, "suffix": "}" },
-    "xpath(input,exp)": { "index": 109, "kind": "function", "displayName": "XPath", "group": "function", "label": "function", "required": false, "javaType": "Object", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "When working with XML data, then this allows using the XPath language, for example, to extract data from the message body (in XML format). This requires having camel-xpath JAR on the classpath. For input (optional), you can choose `header:key`, `exchangeProperty:key` or `variable:key` to use as input for the XML payload instead of the message body.", "ognl": false, "suffix": "}" }
+    "unquote(exp)": { "index": 104, "kind": "function", "displayName": "Unquote", "group": "function", "label": "function", "required": false, "javaType": "String", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "Returns the message body (or expression) with any leading\/ending quotes removed", "ognl": false, "suffix": "}" },
+    "uppercase(exp)": { "index": 105, "kind": "function", "displayName": "Uppercase", "group": "function", "label": "function", "required": false, "javaType": "String", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "Uppercases the message body (or expression)", "ognl": false, "suffix": "}" },
+    "uuid(type)": { "index": 106, "kind": "function", "displayName": "Generate UUID", "group": "function", "label": "function", "required": false, "javaType": "String", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "Returns a UUID using the Camel `UuidGenerator`. You can choose between `default`, `classic`, `short` and `simple` as the type. If no type is given, the default is used. It is also possible to use a custom `UuidGenerator` and bind the bean to the Registry with an id. For example `${uuid(myGenerator)}` where the ID is _myGenerator_.", "ognl": false, "suffix": "}" },
+    "variable.name": { "index": 107, "kind": "function", "displayName": "Variable", "group": "function", "label": "function", "required": false, "javaType": "Object", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "The variable with the given name", "ognl": true, "suffix": "}" },
+    "variableAs(key,type)": { "index": 108, "kind": "function", "displayName": "Variable As", "group": "function", "label": "function", "required": false, "javaType": "Object", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "Converts the variable to the given type (classname).", "ognl": false, "suffix": "}" },
+    "variables": { "index": 109, "kind": "function", "displayName": "Variables", "group": "function", "label": "function", "required": false, "javaType": "java.util.Map", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "Returns all the variables from the current Exchange in a Map", "ognl": false, "suffix": "}" },
+    "xpath(input,exp)": { "index": 110, "kind": "function", "displayName": "XPath", "group": "function", "label": "function", "required": false, "javaType": "Object", "prefix": "${", "deprecated": false, "deprecationNote": "", "autowired": false, "secret": false, "description": "When working with XML data, then this allows using the XPath language, for example, to extract data from the message body (in XML format). This requires having camel-xpath JAR on the classpath. For input (optional), you can choose `header:key`, `exchangeProperty:key` or `variable:key` to use as input for the XML payload instead of the message body.", "ognl": false, "suffix": "}" }
   }
 }
diff --git a/...camel-core-languages/src/main/docs/modules/languages/pages/simple-language.adoc b/...camel-core-languages/src/main/docs/modules/languages/pages/simple-language.adoc
@@ -473,6 +473,8 @@ The generator supports different kinds `default`, `classic`, `short`, `simple` a
 |`substringBetween(exp,after,before` | `String` | Returns a substring of the expression that are between before and after. Returns `null` if nothing comes between.
 |`trim()` | `String` | The trim function trims the message body by removing all leading and trailing white spaces.
 |`trim(exp)` | `String` | The trim function trims the expression by removing all leading and trailing white spaces.
+|`unquote()` | `String` | Returns the message body with any leading/ending quotes removed
+|`unquote(exp)` | `String` | Returns the expression with any leading/ending quotes removed
 |`quote()` | `String` | Returns the message body as a double-quoted string
 |`quote(exp)` | `String` | Returns the expression as a double-quoted string
 |`uppercase()` | `String` | Uppercases the message body
@@ -1299,8 +1301,6 @@ $init{
 }init$
 ----
 
-NOTE: You cannot declare custom functions that call other function functions. This is currently not supported.
-
 The function will by default use the message body as the input, such that the following:
 
 [source,java]
@@ -1319,6 +1319,33 @@ simple("Incoming message: ${cleanUp('  Please   clean  this   text for    me ')}
 
 Here the parameter is a fixed `String` but you can also pass in other type of value such as a number, boolean, or even a nested function.
 
+==== Calling custom functions from custom functions
+
+It is also possible to reuse custom functions from other functions using `${function(name)}`, such shown:
+
+[source,text]
+----
+$init{
+  $cleanUp ~:= ${trim()} ~> ${normalizeWhitespace()} ~> ${uppercase()}
+  $count ~:= ${function(cleanUp)} ~> ${split(' ')} ~> ${size()}
+}init$
+----
+
+Here the `$count` is declared as a function which calls the cleanUp function and then counts the words via split and size functions.
+
+Instead of using `${function(name)}` you can also same syntax as the built-in functions, as follows:
+
+[source,text]
+----
+$init{
+  $cleanUp ~:= ${trim()} ~> ${normalizeWhitespace()} ~> ${uppercase()}
+  $count ~:= ${cleanUp()} ~> ${split(' ')} ~> ${size()}
+}init$
+----
+
+Notice how `${cleanUp()}` despite being a custom function is using the same syntax as all the built-in functions that are being used, for example:
+ `${trim()}`.
+
 
 == OGNL Expression Support
 

diff --git a/core/camel-core-languages/src/main/java/org/apache/camel/language/csimple/CSimpleHelper.java b/core/camel-core-languages/src/main/java/org/apache/camel/language/csimple/CSimpleHelper.java
@@ -1075,6 +1075,19 @@ public static Object safeQuote(Exchange exchange, Object value) {
         return value;
     }
 
+    public static String unquote(Exchange exchange, Object value) {
+        String body;
+        if (value != null) {
+            body = exchange.getContext().getTypeConverter().tryConvertTo(String.class, exchange, value);
+        } else {
+            body = exchange.getMessage().getBody(String.class);
+        }
+        if (body != null) {
+            body = StringHelper.removeLeadingAndEndingQuotes(body);
+        }
+        return body;
+    }
+
     public static String trim(Exchange exchange, Object value) {
         String body;
         if (value != null) {

diff --git a/.../camel-core-languages/src/main/java/org/apache/camel/language/simple/SimpleConstants.java b/.../camel-core-languages/src/main/java/org/apache/camel/language/simple/SimpleConstants.java
@@ -421,6 +421,10 @@ public final class SimpleConstants {
               label = "function", javaType = "Object", displayName = "Kind of Type")
     public static final String KIND_OF_TYPE = "kindOfType(exp)";
 
+    @Metadata(description = "Returns the message body (or expression) with any leading/ending quotes removed",
+              label = "function", javaType = "String")
+    public static final String UNQUOTE = "unquote(exp)";
+
     @Metadata(description = "Uppercases the message body (or expression)", label = "function", javaType = "String",
               displayName = "Uppercase")
     public static final String UPPERCASE = "uppercase(exp)";