Add ValueProvider.kt

build.gradle.kts

@@ -4,7 +4,7 @@ plugins {
 
 allprojects {
     group = "space.kscience"
-    version = "0.5.0-dev-10"
+    version = "0.5.0-dev-11"
 }
 
 subprojects {

dataforge-meta/src/commonMain/kotlin/space/kscience/dataforge/meta/Meta.kt

@@ -19,8 +19,10 @@ public interface MetaRepr {
 /**
  * A container for meta nodes
  */
-public fun interface MetaProvider {
+public fun interface MetaProvider : ValueProvider {
     public fun getMeta(name: Name): Meta?
+
+    override fun getValue(name: Name): Value? = getMeta(name)?.value
 }
 
 /**

dataforge-meta/src/commonMain/kotlin/space/kscience/dataforge/meta/MutableMeta.kt

@@ -4,6 +4,7 @@ import kotlinx.serialization.Serializable
 import space.kscience.dataforge.misc.DFExperimental
 import space.kscience.dataforge.names.*
 import space.kscience.dataforge.values.EnumValue
+import space.kscience.dataforge.values.MutableValueProvider
 import space.kscience.dataforge.values.Value
 import space.kscience.dataforge.values.asValue
 import kotlin.js.JsName
@@ -19,10 +20,12 @@ public annotation class MetaBuilder
 /**
  * A generic interface that gives access to getting and setting meta notes and values
  */
-public interface MutableMetaProvider : MetaProvider {
+public interface MutableMetaProvider : MetaProvider, MutableValueProvider {
     override fun getMeta(name: Name): MutableMeta?
     public fun setMeta(name: Name, node: Meta?)
-    public fun setValue(name: Name, value: Value?)
+    override fun setValue(name: Name, value: Value?) {
+        getMeta(name)?.value = value
+    }
 }
 
 /**

dataforge-meta/src/commonMain/kotlin/space/kscience/dataforge/meta/Scheme.kt

@@ -12,8 +12,14 @@ import kotlin.jvm.Synchronized
  */
 public open class Scheme : Described, MetaRepr, MutableMetaProvider, Configurable {
 
+    /**
+     * Meta to be mutated by this schme
+     */
     private var targetMeta: MutableMeta = MutableMeta()
 
+    /**
+     * Default values provided by this scheme
+     */
     private var defaultMeta: Meta? = null
 
     final override val meta: ObservableMutableMeta = SchemeMeta(Name.EMPTY)
@@ -62,12 +68,14 @@ public open class Scheme : Described, MetaRepr, MutableMetaProvider, Configurabl
 
     private inner class SchemeMeta(val pathName: Name) : ObservableMutableMeta {
         override var value: Value?
-            get() = targetMeta[pathName]?.value ?: defaultMeta?.get(pathName)?.value
+            get() = targetMeta[pathName]?.value
+                ?: defaultMeta?.get(pathName)?.value
+                ?: descriptor?.get(pathName)?.defaultValue
             set(value) {
                 val oldValue = targetMeta[pathName]?.value
                 targetMeta[pathName] = value
                 if (oldValue != value) {
-                    invalidate(pathName)
+                    invalidate(Name.EMPTY)
                 }
             }
 
@@ -84,9 +92,9 @@ public open class Scheme : Described, MetaRepr, MutableMetaProvider, Configurabl
 
         @Synchronized
         override fun onChange(owner: Any?, callback: Meta.(name: Name) -> Unit) {
-            listeners.add(MetaListener(owner) { changedeName ->
+            listeners.add(MetaListener(owner) { changedName ->
-                if (changedeName.startsWith(pathName)) {
+                if (changedName.startsWith(pathName)) {
-                    this@Scheme.meta.callback(changedeName.removeHeadOrNull(pathName)!!)
+                    this@Scheme.meta.callback(changedName.removeHeadOrNull(pathName)!!)
                 }
             })
         }

dataforge-meta/src/commonMain/kotlin/space/kscience/dataforge/values/ValueProvider.kt

@@ -0,0 +1,17 @@
+package space.kscience.dataforge.values
+
+import space.kscience.dataforge.names.Name
+
+/**
+ * An object that could provide values
+ */
+public fun interface ValueProvider {
+    public fun getValue(name: Name): Value?
+}
+
+/**
+ * An object that could consume values
+ */
+public interface MutableValueProvider: ValueProvider{
+    public fun setValue(name: Name, value: Value?)
+}