diff options
Diffstat (limited to 'kamon-core/src/main/scala/kamon/util/MapMerge.scala')
-rw-r--r-- | kamon-core/src/main/scala/kamon/util/MapMerge.scala | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/kamon-core/src/main/scala/kamon/util/MapMerge.scala b/kamon-core/src/main/scala/kamon/util/MapMerge.scala new file mode 100644 index 00000000..b7f18788 --- /dev/null +++ b/kamon-core/src/main/scala/kamon/util/MapMerge.scala @@ -0,0 +1,27 @@ +package kamon.util + +object MapMerge { + + /** + * Merge to immutable maps with the same key and value types, using the provided valueMerge function. + */ + implicit class Syntax[K, V](val map: Map[K, V]) extends AnyVal { + def merge(that: Map[K, V], valueMerge: (V, V) ⇒ V): Map[K, V] = { + val merged = Map.newBuilder[K, V] + + map.foreach { + case (key, value) ⇒ + val mergedValue = that.get(key).map(v ⇒ valueMerge(value, v)).getOrElse(value) + merged += key -> mergedValue + } + + that.foreach { + case kv @ (key, _) if !map.contains(key) ⇒ merged += kv + case other ⇒ // ignore, already included. + } + + merged.result(); + } + } + +} |