diff --git a/modules/swagger-codegen/src/main/resources/swift3/Models.mustache b/modules/swagger-codegen/src/main/resources/swift3/Models.mustache
index e8fa94d0e0..f8c312452e 100644
--- a/modules/swagger-codegen/src/main/resources/swift3/Models.mustache
+++ b/modules/swagger-codegen/src/main/resources/swift3/Models.mustache
@@ -125,11 +125,11 @@ class Decoders {
 
     static func decode<T>(clazz: T.Type, source: AnyObject, instance: AnyObject?) -> Decoded<T> {
         initialize()
-        if let value = source.int32Value as? T, source is NSNumber, T.self is Int32.Type {
+        if let sourceNumber = source as? NSNumber, let value = sourceNumber.int32Value as? T, T.self is Int32.Type {
             return .success(value)
         }
-        if let value = source.int32Value as? T, source is NSNumber, T.self is Int64.Type {
-            return .success(value)
+        if let sourceNumber = source as? NSNumber, let value = sourceNumber.int32Value as? T, T.self is Int64.Type {
+     	    return .success(value)
         }
         if let intermediate = source as? String, let value = UUID(uuidString: intermediate) as? T, source is String, T.self is UUID.Type {
             return .success(value)
diff --git a/samples/client/petstore/swift3/default/PetstoreClient/Classes/Swaggers/Models.swift b/samples/client/petstore/swift3/default/PetstoreClient/Classes/Swaggers/Models.swift
index 1258d5940d..fa325a0e96 100644
--- a/samples/client/petstore/swift3/default/PetstoreClient/Classes/Swaggers/Models.swift
+++ b/samples/client/petstore/swift3/default/PetstoreClient/Classes/Swaggers/Models.swift
@@ -125,11 +125,11 @@ class Decoders {
 
     static func decode<T>(clazz: T.Type, source: AnyObject, instance: AnyObject?) -> Decoded<T> {
         initialize()
-        if let value = source.int32Value as? T, source is NSNumber, T.self is Int32.Type {
+        if let sourceNumber = source as? NSNumber, let value = sourceNumber.int32Value as? T, T.self is Int32.Type {
             return .success(value)
         }
-        if let value = source.int32Value as? T, source is NSNumber, T.self is Int64.Type {
-            return .success(value)
+        if let sourceNumber = source as? NSNumber, let value = sourceNumber.int32Value as? T, T.self is Int64.Type {
+     	    return .success(value)
         }
         if let intermediate = source as? String, let value = UUID(uuidString: intermediate) as? T, source is String, T.self is UUID.Type {
             return .success(value)
diff --git a/samples/client/petstore/swift3/promisekit/PetstoreClient/Classes/Swaggers/Models.swift b/samples/client/petstore/swift3/promisekit/PetstoreClient/Classes/Swaggers/Models.swift
index 1258d5940d..fa325a0e96 100644
--- a/samples/client/petstore/swift3/promisekit/PetstoreClient/Classes/Swaggers/Models.swift
+++ b/samples/client/petstore/swift3/promisekit/PetstoreClient/Classes/Swaggers/Models.swift
@@ -125,11 +125,11 @@ class Decoders {
 
     static func decode<T>(clazz: T.Type, source: AnyObject, instance: AnyObject?) -> Decoded<T> {
         initialize()
-        if let value = source.int32Value as? T, source is NSNumber, T.self is Int32.Type {
+        if let sourceNumber = source as? NSNumber, let value = sourceNumber.int32Value as? T, T.self is Int32.Type {
             return .success(value)
         }
-        if let value = source.int32Value as? T, source is NSNumber, T.self is Int64.Type {
-            return .success(value)
+        if let sourceNumber = source as? NSNumber, let value = sourceNumber.int32Value as? T, T.self is Int64.Type {
+     	    return .success(value)
         }
         if let intermediate = source as? String, let value = UUID(uuidString: intermediate) as? T, source is String, T.self is UUID.Type {
             return .success(value)
diff --git a/samples/client/petstore/swift3/rxswift/PetstoreClient/Classes/Swaggers/Models.swift b/samples/client/petstore/swift3/rxswift/PetstoreClient/Classes/Swaggers/Models.swift
index 1258d5940d..fa325a0e96 100644
--- a/samples/client/petstore/swift3/rxswift/PetstoreClient/Classes/Swaggers/Models.swift
+++ b/samples/client/petstore/swift3/rxswift/PetstoreClient/Classes/Swaggers/Models.swift
@@ -125,11 +125,11 @@ class Decoders {
 
     static func decode<T>(clazz: T.Type, source: AnyObject, instance: AnyObject?) -> Decoded<T> {
         initialize()
-        if let value = source.int32Value as? T, source is NSNumber, T.self is Int32.Type {
+        if let sourceNumber = source as? NSNumber, let value = sourceNumber.int32Value as? T, T.self is Int32.Type {
             return .success(value)
         }
-        if let value = source.int32Value as? T, source is NSNumber, T.self is Int64.Type {
-            return .success(value)
+        if let sourceNumber = source as? NSNumber, let value = sourceNumber.int32Value as? T, T.self is Int64.Type {
+     	    return .success(value)
         }
         if let intermediate = source as? String, let value = UUID(uuidString: intermediate) as? T, source is String, T.self is UUID.Type {
             return .success(value)
diff --git a/samples/client/petstore/swift3/unwraprequired/PetstoreClient/Classes/Swaggers/Models.swift b/samples/client/petstore/swift3/unwraprequired/PetstoreClient/Classes/Swaggers/Models.swift
index bcc2197e41..40c6256086 100644
--- a/samples/client/petstore/swift3/unwraprequired/PetstoreClient/Classes/Swaggers/Models.swift
+++ b/samples/client/petstore/swift3/unwraprequired/PetstoreClient/Classes/Swaggers/Models.swift
@@ -125,11 +125,11 @@ class Decoders {
 
     static func decode<T>(clazz: T.Type, source: AnyObject, instance: AnyObject?) -> Decoded<T> {
         initialize()
-        if let value = source.int32Value as? T, source is NSNumber, T.self is Int32.Type {
+        if let sourceNumber = source as? NSNumber, let value = sourceNumber.int32Value as? T, T.self is Int32.Type {
             return .success(value)
         }
-        if let value = source.int32Value as? T, source is NSNumber, T.self is Int64.Type {
-            return .success(value)
+        if let sourceNumber = source as? NSNumber, let value = sourceNumber.int32Value as? T, T.self is Int64.Type {
+     	    return .success(value)
         }
         if let intermediate = source as? String, let value = UUID(uuidString: intermediate) as? T, source is String, T.self is UUID.Type {
             return .success(value)