initial import

core/mapping/valuer.go

@@ -0,0 +1,14 @@
+package mapping
+
+type (
+	Valuer interface {
+		Value(key string) (interface{}, bool)
+	}
+
+	MapValuer map[string]interface{}
+)
+
+func (mv MapValuer) Value(key string) (interface{}, bool) {
+	v, ok := mv[key]
+	return v, ok
+}