2 files changed, 85 insertions, 45 deletions
diff --git a/walk/walk.go b/walk/walk.go
index 3fba62f..e66feff 100644
--- a/walk/walk.go
+++ b/walk/walk.go
@@ -148,3 +148,88 @@ func (item WalkItem) Debug() string {
 	builder.WriteString(item.Value.Debug())
 	return builder.String()
 }
+
+func Merge(first Value, second Value) []Value {
+	switch first := first.(type) {
+	case NullValue:
+		return []Value {first, second}
+	case BoolValue:
+		return []Value {first, second}
+	case NumberValue:
+		return []Value {first, second}
+	case StringValue:
+		return []Value {first, second}
+	case ArrayValue:
+		secondArr, isArr := second.(ArrayValue)
+		if !isArr {
+			return []Value {first, second}
+		}
+
+		if len(first) == 0 {
+			return []Value {second}
+		}
+
+		if len(secondArr) == 0 {
+			return []Value {first}
+		}
+
+		var res ArrayValue
+		for _, el := range first[:len(first) - 1] {
+			res = append(res, el)
+		}
+		midFirst := first[len(first) - 1]
+		midSecond := secondArr[0]
+		if midFirst.Index == midSecond.Index {
+			for _, el := range Merge(midFirst.Value, midSecond.Value) {
+				res = append(res, ArrayElement {
+					Index: midFirst.Index,
+					Value: el,
+				})
+			}
+		} else {
+			res = append(res, midFirst, midSecond)
+		}
+		for _, el := range secondArr[1:] {
+			res = append(res, el)
+		}
+
+		return []Value {res}
+	case MapValue:
+		secondMap, isMap := second.(MapValue)
+		if !isMap {
+			return []Value {first, second}
+		}
+
+		if len(first) == 0 {
+			return []Value {second}
+		}
+
+		if len(secondMap) == 0 {
+			return []Value {first}
+		}
+
+		var res MapValue
+		for _, el := range first[:len(first) - 1] {
+			res = append(res, el)
+		}
+		midFirst := first[len(first) - 1]
+		midSecond := secondMap[0]
+		if midFirst.Key == midSecond.Key {
+			for _, el := range Merge(midFirst.Value, midSecond.Value) {
+				res = append(res, MapElement {
+					Key: midFirst.Key,
+					Value: el,
+				})
+			}
+		} else {
+			res = append(res, midFirst, midSecond)
+		}
+		for _, el := range secondMap[1:] {
+			res = append(res, el)
+		}
+
+		return []Value {res}
+	default:
+		panic("first is invalid value type")
+	}
+}
diff --git a/walk/walk_test.go b/walk/walk_test.go
deleted file mode 100644
index 759c501..0000000
--- a/walk/walk_test.go
+++ /dev/null
@@ -1,45 +0,0 @@
-package walk
-
-import (
-	"testing"
-	"log"
-)
-
-func TestValueIter(t *testing.T) {
-	values := ValueList{
-		NumberValue(1),
-		NumberValue(2),
-		NumberValue(3),
-	}
-
-	valuesCopy := ValueList{}
-
-	iter := NewValueIter(values)
-
-	for {
-		edible := iter.Next()
-		if edible == nil {
-			break
-		}
-
-		log.Println(edible)
-
-		value, isValue := edible.(Value)
-
-		if !isValue {
-			t.Fatalf("Iterator produced a non-value")
-		}
-
-		valuesCopy = append(valuesCopy, value)
-	}
-
-	if len(values) != len(valuesCopy) {
-		t.Fatalf("iter gave the wrong number of values")
-	}
-
-	for i, value := range values {
-		if value != valuesCopy[i] {
-			t.Fatalf("iter produced an incorrect value")
-		}
-	}
-}