Optimize Name hashCode

CHANGELOG.md

@@ -9,6 +9,7 @@
 - More fine-grained types in Action builders.
 
 ### Changed
+- Meta `get` method allows nullable receiver
 - `withDefault` functions do not add new keys to meta children and are consistent.
 - `dataforge.meta.values` package is merged into `dataforge.meta` for better star imports
 - Kotlin 1.7.20

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

@@ -5,6 +5,7 @@ import kotlinx.serialization.json.Json
 import space.kscience.dataforge.misc.Type
 import space.kscience.dataforge.misc.unsafeCast
 import space.kscience.dataforge.names.*
+import kotlin.jvm.JvmName
 
 
 /**
@@ -94,6 +95,10 @@ public interface Meta : MetaRepr, MetaProvider {
 public val Meta.isLeaf: Boolean get() = items.isEmpty()
 
 
+public operator fun Meta?.get(token: NameToken): Meta? = this?.items?.get(token)
+
+@Deprecated("Use nullable receiver", level = DeprecationLevel.HIDDEN)
+@JvmName("getNonNullable")
 public operator fun Meta.get(token: NameToken): Meta? = items[token]
 
 /**
@@ -103,11 +108,19 @@ public operator fun Meta.get(token: NameToken): Meta? = items[token]
  */
 public operator fun Meta?.get(name: Name): Meta? = this?.getMeta(name)
 
+@Deprecated("Use nullable receiver", level = DeprecationLevel.HIDDEN)
+@JvmName("getNonNullable")
+public operator fun Meta.get(name: Name): Meta? = getMeta(name)
+
 /**
  * Parse [Name] from [key] using full name notation and pass it to [Meta.get]
  */
 public operator fun Meta?.get(key: String): Meta? = this?.get(key.parseAsName(true))
 
+@Deprecated("Use nullable receiver", level = DeprecationLevel.HIDDEN)
+@JvmName("getNonNullable")
+public operator fun Meta.get(key: String): Meta? = get(key.parseAsName(true))
+
 /**
  * Get all items matching given name. The index of the last element, if present is used as a [Regex],
  * against which indexes of elements are matched.
@@ -162,7 +175,7 @@ public inline val <M : TypedMeta<M>> TypedMeta<M>.self: M get() = unsafeCast()
 
 //public typealias Meta = TypedMeta<*>
 
-public operator fun <M : TypedMeta<M>> TypedMeta<M>.get(token: NameToken): M? = items[token]
+public operator fun <M : TypedMeta<M>> TypedMeta<M>?.get(token: NameToken): M? = this?.items?.get(token)
 
 /**
  * Perform recursive item search using given [name]. Each [NameToken] is treated as a name in [TypedMeta.items] of a parent node.
@@ -175,11 +188,19 @@ public tailrec operator fun <M : TypedMeta<M>> TypedMeta<M>?.get(name: Name): M?
     else -> get(name.firstOrNull()!!)?.get(name.cutFirst())
 }
 
+@Deprecated("Use nullable receiver", level = DeprecationLevel.HIDDEN)
+@JvmName("getNonNullable")
+public operator fun <M : TypedMeta<M>> TypedMeta<M>.get(name: Name): M? = get(name)
+
 /**
  * Parse [Name] from [key] using full name notation and pass it to [TypedMeta.get]
  */
 public operator fun <M : TypedMeta<M>> TypedMeta<M>?.get(key: String): M? = this[key.parseAsName(true)]
 
+@Deprecated("Use nullable receiver", level = DeprecationLevel.HIDDEN)
+@JvmName("getNonNullable")
+public operator fun <M : TypedMeta<M>> TypedMeta<M>.get(key: String): M? = get(key)
+
 
 /**
  * Get a sequence of [Name]-[Value] pairs using top-down traversal of the tree

dataforge-meta/src/commonMain/kotlin/space/kscience/dataforge/names/Name.kt

@@ -24,14 +24,14 @@ public class Name(public val tokens: List<NameToken>) {
         }
     }
 
-    override fun hashCode(): Int {
+    private val cachedHashCode = if (tokens.size == 1) {
-        return if (tokens.size == 1) {
+        tokens.first().hashCode()
-            tokens.first().hashCode()
+    } else {
-        } else {
+        tokens.hashCode()
-            tokens.hashCode()
-        }
     }
 
+    override fun hashCode(): Int = cachedHashCode
+
     public companion object {
         public const val NAME_SEPARATOR: String = "."
 

dataforge-meta/src/commonMain/kotlin/space/kscience/dataforge/names/NameToken.kt

@@ -9,7 +9,7 @@ import space.kscience.dataforge.misc.DFExperimental
  * A name token could have appendix in square brackets called *index*
  */
 @Serializable(NameTokenSerializer::class)
-public data class NameToken(val body: String, val index: String? = null) {
+public class NameToken(public val body: String, public val index: String? = null) {
 
     init {
         if (body.isEmpty()) error("Syntax error: Name token body is empty")
@@ -33,6 +33,7 @@ public data class NameToken(val body: String, val index: String? = null) {
         bodyEscaped
     }
 
+
     /**
      * Return unescaped version of the [NameToken]. Should be used only for output because it is not possible to correctly
      * parse it back.
@@ -43,6 +44,22 @@ public data class NameToken(val body: String, val index: String? = null) {
         body
     }
 
+    override fun equals(other: Any?): Boolean {
+        if (this === other) return true
+        if (other == null || this::class != other::class) return false
+
+        other as NameToken
+
+        if (body != other.body) return false
+        if (index != other.index) return false
+
+        return true
+    }
+
+    private val cachedHashCode = body.hashCode() * 31 + (index?.hashCode() ?: 0)
+
+    override fun hashCode(): Int = cachedHashCode
+
     public companion object {
 
         private val escapedChars = listOf('\\', '.', '[', ']')

dataforge-meta/src/jsMain/kotlin/space/kscience/dataforge/meta/DynamicMeta.kt

@@ -33,7 +33,7 @@ public fun Meta.toDynamic(): dynamic {
 public class DynamicMeta(internal val obj: dynamic) : TypedMeta<DynamicMeta> {
     private fun keys(): Array<String> = js("Object").keys(obj) as Array<String>
 
-    private fun isArray(@Suppress("UNUSED_PARAMETER") obj: dynamic): Boolean =
+    private fun isArray(obj: dynamic): Boolean =
         js("Array").isArray(obj) as Boolean
 
     private fun isPrimitive(obj: dynamic): Boolean =