diff --git a/samples/client/petstore/swift4/default/PetstoreClient/Classes/OpenAPIs/APIHelper.swift b/samples/client/petstore/swift4/default/PetstoreClient/Classes/OpenAPIs/APIHelper.swift
index 200070096800a34d3800caa7093e07fced09d00b..75dea24395752b328facec8e593fcac7ea470217 100644
--- a/samples/client/petstore/swift4/default/PetstoreClient/Classes/OpenAPIs/APIHelper.swift
+++ b/samples/client/petstore/swift4/default/PetstoreClient/Classes/OpenAPIs/APIHelper.swift
@@ -22,7 +22,7 @@ public struct APIHelper {
 
     public static func rejectNilHeaders(_ source: [String: Any?]) -> [String: String] {
         return source.reduce(into: [String: String]()) { (result, item) in
-            if let collection = item.value as? [Any?] {
+            if let collection = item.value as? Array<Any?> {
                 result[item.key] = collection.filter({ $0 != nil }).map { "\($0!)" }.joined(separator: ",")
             } else if let value: Any = item.value {
                 result[item.key] = "\(value)"
@@ -46,7 +46,7 @@ public struct APIHelper {
     }
 
     public static func mapValueToPathItem(_ source: Any) -> Any {
-        if let collection = source as? [Any?] {
+        if let collection = source as? Array<Any?> {
             return collection.filter({ $0 != nil }).map({"\($0!)"}).joined(separator: ",")
         }
         return source
@@ -54,7 +54,7 @@ public struct APIHelper {
 
     public static func mapValuesToQueryItems(_ source: [String: Any?]) -> [URLQueryItem]? {
         let destination = source.filter({ $0.value != nil}).reduce(into: [URLQueryItem]()) { (result, item) in
-            if let collection = item.value as? [Any?] {
+            if let collection = item.value as? Array<Any?> {
                 let value = collection.filter({ $0 != nil }).map({"\($0!)"}).joined(separator: ",")
                 result.append(URLQueryItem(name: item.key, value: value))
             } else if let value = item.value {
diff --git a/samples/client/petstore/swift4/objcCompatible/PetstoreClient/Classes/OpenAPIs/APIHelper.swift b/samples/client/petstore/swift4/objcCompatible/PetstoreClient/Classes/OpenAPIs/APIHelper.swift
index 200070096800a34d3800caa7093e07fced09d00b..75dea24395752b328facec8e593fcac7ea470217 100644
--- a/samples/client/petstore/swift4/objcCompatible/PetstoreClient/Classes/OpenAPIs/APIHelper.swift
+++ b/samples/client/petstore/swift4/objcCompatible/PetstoreClient/Classes/OpenAPIs/APIHelper.swift
@@ -22,7 +22,7 @@ public struct APIHelper {
 
     public static func rejectNilHeaders(_ source: [String: Any?]) -> [String: String] {
         return source.reduce(into: [String: String]()) { (result, item) in
-            if let collection = item.value as? [Any?] {
+            if let collection = item.value as? Array<Any?> {
                 result[item.key] = collection.filter({ $0 != nil }).map { "\($0!)" }.joined(separator: ",")
             } else if let value: Any = item.value {
                 result[item.key] = "\(value)"
@@ -46,7 +46,7 @@ public struct APIHelper {
     }
 
     public static func mapValueToPathItem(_ source: Any) -> Any {
-        if let collection = source as? [Any?] {
+        if let collection = source as? Array<Any?> {
             return collection.filter({ $0 != nil }).map({"\($0!)"}).joined(separator: ",")
         }
         return source
@@ -54,7 +54,7 @@ public struct APIHelper {
 
     public static func mapValuesToQueryItems(_ source: [String: Any?]) -> [URLQueryItem]? {
         let destination = source.filter({ $0.value != nil}).reduce(into: [URLQueryItem]()) { (result, item) in
-            if let collection = item.value as? [Any?] {
+            if let collection = item.value as? Array<Any?> {
                 let value = collection.filter({ $0 != nil }).map({"\($0!)"}).joined(separator: ",")
                 result.append(URLQueryItem(name: item.key, value: value))
             } else if let value = item.value {
diff --git a/samples/client/petstore/swift4/promisekitLibrary/Package.swift b/samples/client/petstore/swift4/promisekitLibrary/Package.swift
index fbf22f5f82367e0d525a52bc9931a032fc386dc6..7ba5c67b456ca2509bfb00d5b903538098b1759f 100644
--- a/samples/client/petstore/swift4/promisekitLibrary/Package.swift
+++ b/samples/client/petstore/swift4/promisekitLibrary/Package.swift
@@ -9,12 +9,12 @@ let package = Package(
         // Products define the executables and libraries produced by a package, and make them visible to other packages.
         .library(
             name: "PetstoreClient",
-            targets: ["PetstoreClient"]),
+            targets: ["PetstoreClient"])
     ],
     dependencies: [
         // Dependencies declare other packages that this package depends on.
         .package(url: "https://github.com/Alamofire/Alamofire.git", from: "4.9.0"),
-        .package(url: "https://github.com/mxcl/PromiseKit.git", from: "6.11.0"),
+        .package(url: "https://github.com/mxcl/PromiseKit.git", from: "6.11.0")
     ],
     targets: [
         // Targets are the basic building blocks of a package. A target can define a module or a test suite.
@@ -23,6 +23,6 @@ let package = Package(
             name: "PetstoreClient",
             dependencies: ["Alamofire", "PromiseKit"],
             path: "PetstoreClient/Classes"
-        ),
+        )
     ]
 )
diff --git a/samples/client/petstore/swift4/promisekitLibrary/PetstoreClient/Classes/OpenAPIs/APIHelper.swift b/samples/client/petstore/swift4/promisekitLibrary/PetstoreClient/Classes/OpenAPIs/APIHelper.swift
index 200070096800a34d3800caa7093e07fced09d00b..75dea24395752b328facec8e593fcac7ea470217 100644
--- a/samples/client/petstore/swift4/promisekitLibrary/PetstoreClient/Classes/OpenAPIs/APIHelper.swift
+++ b/samples/client/petstore/swift4/promisekitLibrary/PetstoreClient/Classes/OpenAPIs/APIHelper.swift
@@ -22,7 +22,7 @@ public struct APIHelper {
 
     public static func rejectNilHeaders(_ source: [String: Any?]) -> [String: String] {
         return source.reduce(into: [String: String]()) { (result, item) in
-            if let collection = item.value as? [Any?] {
+            if let collection = item.value as? Array<Any?> {
                 result[item.key] = collection.filter({ $0 != nil }).map { "\($0!)" }.joined(separator: ",")
             } else if let value: Any = item.value {
                 result[item.key] = "\(value)"
@@ -46,7 +46,7 @@ public struct APIHelper {
     }
 
     public static func mapValueToPathItem(_ source: Any) -> Any {
-        if let collection = source as? [Any?] {
+        if let collection = source as? Array<Any?> {
             return collection.filter({ $0 != nil }).map({"\($0!)"}).joined(separator: ",")
         }
         return source
@@ -54,7 +54,7 @@ public struct APIHelper {
 
     public static func mapValuesToQueryItems(_ source: [String: Any?]) -> [URLQueryItem]? {
         let destination = source.filter({ $0.value != nil}).reduce(into: [URLQueryItem]()) { (result, item) in
-            if let collection = item.value as? [Any?] {
+            if let collection = item.value as? Array<Any?> {
                 let value = collection.filter({ $0 != nil }).map({"\($0!)"}).joined(separator: ",")
                 result.append(URLQueryItem(name: item.key, value: value))
             } else if let value = item.value {
diff --git a/samples/client/petstore/swift4/rxswiftLibrary/PetstoreClient/Classes/OpenAPIs/APIHelper.swift b/samples/client/petstore/swift4/rxswiftLibrary/PetstoreClient/Classes/OpenAPIs/APIHelper.swift
index 200070096800a34d3800caa7093e07fced09d00b..75dea24395752b328facec8e593fcac7ea470217 100644
--- a/samples/client/petstore/swift4/rxswiftLibrary/PetstoreClient/Classes/OpenAPIs/APIHelper.swift
+++ b/samples/client/petstore/swift4/rxswiftLibrary/PetstoreClient/Classes/OpenAPIs/APIHelper.swift
@@ -22,7 +22,7 @@ public struct APIHelper {
 
     public static func rejectNilHeaders(_ source: [String: Any?]) -> [String: String] {
         return source.reduce(into: [String: String]()) { (result, item) in
-            if let collection = item.value as? [Any?] {
+            if let collection = item.value as? Array<Any?> {
                 result[item.key] = collection.filter({ $0 != nil }).map { "\($0!)" }.joined(separator: ",")
             } else if let value: Any = item.value {
                 result[item.key] = "\(value)"
@@ -46,7 +46,7 @@ public struct APIHelper {
     }
 
     public static func mapValueToPathItem(_ source: Any) -> Any {
-        if let collection = source as? [Any?] {
+        if let collection = source as? Array<Any?> {
             return collection.filter({ $0 != nil }).map({"\($0!)"}).joined(separator: ",")
         }
         return source
@@ -54,7 +54,7 @@ public struct APIHelper {
 
     public static func mapValuesToQueryItems(_ source: [String: Any?]) -> [URLQueryItem]? {
         let destination = source.filter({ $0.value != nil}).reduce(into: [URLQueryItem]()) { (result, item) in
-            if let collection = item.value as? [Any?] {
+            if let collection = item.value as? Array<Any?> {
                 let value = collection.filter({ $0 != nil }).map({"\($0!)"}).joined(separator: ",")
                 result.append(URLQueryItem(name: item.key, value: value))
             } else if let value = item.value {
diff --git a/samples/client/petstore/swift4/unwrapRequired/PetstoreClient/Classes/OpenAPIs/APIHelper.swift b/samples/client/petstore/swift4/unwrapRequired/PetstoreClient/Classes/OpenAPIs/APIHelper.swift
index 200070096800a34d3800caa7093e07fced09d00b..75dea24395752b328facec8e593fcac7ea470217 100644
--- a/samples/client/petstore/swift4/unwrapRequired/PetstoreClient/Classes/OpenAPIs/APIHelper.swift
+++ b/samples/client/petstore/swift4/unwrapRequired/PetstoreClient/Classes/OpenAPIs/APIHelper.swift
@@ -22,7 +22,7 @@ public struct APIHelper {
 
     public static func rejectNilHeaders(_ source: [String: Any?]) -> [String: String] {
         return source.reduce(into: [String: String]()) { (result, item) in
-            if let collection = item.value as? [Any?] {
+            if let collection = item.value as? Array<Any?> {
                 result[item.key] = collection.filter({ $0 != nil }).map { "\($0!)" }.joined(separator: ",")
             } else if let value: Any = item.value {
                 result[item.key] = "\(value)"
@@ -46,7 +46,7 @@ public struct APIHelper {
     }
 
     public static func mapValueToPathItem(_ source: Any) -> Any {
-        if let collection = source as? [Any?] {
+        if let collection = source as? Array<Any?> {
             return collection.filter({ $0 != nil }).map({"\($0!)"}).joined(separator: ",")
         }
         return source
@@ -54,7 +54,7 @@ public struct APIHelper {
 
     public static func mapValuesToQueryItems(_ source: [String: Any?]) -> [URLQueryItem]? {
         let destination = source.filter({ $0.value != nil}).reduce(into: [URLQueryItem]()) { (result, item) in
-            if let collection = item.value as? [Any?] {
+            if let collection = item.value as? Array<Any?> {
                 let value = collection.filter({ $0 != nil }).map({"\($0!)"}).joined(separator: ",")
                 result.append(URLQueryItem(name: item.key, value: value))
             } else if let value = item.value {