diff --git a/Sources/Lookup/Lookup.swift b/Sources/Lookup/Lookup.swift
index 4d65d71..f8f23b5 100644
--- a/Sources/Lookup/Lookup.swift
+++ b/Sources/Lookup/Lookup.swift
@@ -240,13 +240,34 @@ public struct Lookup: Swift.CustomStringConvertible, Swift.CustomDebugStringConv
         }
     }
     
-    private func castValueToString(value: Any) -> String {
-        if let data = try? JSONSerialization.data(withJSONObject: value, options: .prettyPrinted),
+    private func jsonToPrettyString(value: Any) -> String? {
+        if JSONSerialization.isValidJSONObject(value),
+           let data = try? JSONSerialization.data(withJSONObject: value, options: .prettyPrinted),
            let str = String(data: data, encoding: .utf8)
         {
             return str
         }
-        return "Can not cast value to string"
+        return nil
+    }
+    
+    private func castValueToString(value: Any) -> String {
+        if let str = jsonToPrettyString(value: value) {
+            return str
+        }
+        // map to string
+        switch value {
+        case let dict as Dictionary<String, Any>:
+            let strDict = Dictionary(uniqueKeysWithValues: dict.map { (key: String, value: Any) in
+                (key, "\(value)")
+            })
+            return jsonToPrettyString(value: strDict) ?? "\(strDict)"
+            
+        case let arr as [Any]:
+            return jsonToPrettyString(value: arr) ?? "\(arr)"
+            
+        default:
+            return "\(value)"
+        }
     }
     
     public var description: String {
diff --git a/Tests/LookupTests/LookupTests.swift b/Tests/LookupTests/LookupTests.swift
index 42dae91..b7e3360 100644
--- a/Tests/LookupTests/LookupTests.swift
+++ b/Tests/LookupTests/LookupTests.swift
@@ -1,6 +1,9 @@
 import XCTest
 @testable import Lookup
 import Foundation
+#if os(iOS)
+import UIKit
+#endif
 
 enum AnimalType {
     case dog, cat
@@ -244,7 +247,19 @@ final class LookupTests: XCTestCase {
             lookup["age"] = "8"
             XCTAssertEqual(lookup.age.int, 8)
         }
-        
         try codable()
+        
+        #if os(iOS)
+        func uiView() throws {
+            let view = UIView()
+            let lookup = Lookup(["view": view])
+            XCTAssertEqual(lookup.description, """
+{
+  "view" : "\(view)"
+}
+""")
+        }
+        try uiView()
+        #endif
     }
 }