Fixed value delegate nullability bug.

build.gradle.kts

@@ -1,4 +1,4 @@
-val dataforgeVersion by extra("0.1.3-dev-4")
+val dataforgeVersion by extra("0.1.3-dev-5")
 
 allprojects {
     repositories {

dataforge-meta/src/commonMain/kotlin/hep/dataforge/meta/ConfigDelegates.kt

@@ -14,7 +14,7 @@ fun Configurable.value(default: Any = Null, key: String? = null): MutableValueDe
     MutableValueDelegate(config, key, Value.of(default))
 
 fun <T> Configurable.value(default: T? = null, key: String? = null, transform: (Value?) -> T): ReadWriteDelegateWrapper<Value?, T> =
-    MutableValueDelegate(config, key, Value.of(default)).transform(reader = transform)
+    MutableValueDelegate(config, key, default?.let { Value.of(it)}).transform(reader = transform)
 
 fun Configurable.string(default: String? = null, key: String? = null): MutableStringDelegate<Config> =
     MutableStringDelegate(config, key, default)

dataforge-meta/src/commonTest/kotlin/hep/dataforge/descriptors/DescriptorTest.kt

@@ -0,0 +1,31 @@
+package hep.dataforge.descriptors
+
+import hep.dataforge.values.ValueType
+import kotlin.test.Test
+import kotlin.test.assertEquals
+
+class DescriptorTest {
+
+    val descriptor = NodeDescriptor.build {
+        node("aNode") {
+            info = "A root demo node"
+            value("b") {
+                info = "b number value"
+                type(ValueType.NUMBER)
+            }
+            node("otherNode") {
+                value("otherValue") {
+                    type(ValueType.BOOLEAN)
+                    default(false)
+                    info = "default value"
+                }
+            }
+        }
+    }
+
+    @Test
+    fun testAllowedValues() {
+        val allowed = descriptor.nodes["aNode"]?.values?.get("b")?.allowedValues
+        assertEquals(allowed, emptyList())
+    }
+}