Code migration from Swift 2.x to Swift 4

swift swift2 xcode8 xcode9-beta swift4
RayofHope picture RayofHope · Jun 7, 2017 · Viewed 25k times · Source

We have big enough project which is built up with Swift 2.x and now Apple has just released Swift 4 so to move forward for latest version of Swift which path we can choose...

Do we need to migrate our code to Swift 3 first? Or we can directly migrate our code to Swift 4 using Xcode 9?

Answer

Krunal picture Krunal · Jun 7, 2017

Yes, you must migrate your code in Swift 3 compatible version. Xcode 9 allows conversion/migration from swift 3.0 only.

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Swift 3.2 is supported by Xcode 9 & Xcode 8 both.

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Convert your source code from Swift 2.0 to 3.2 using Xcode 8 and then continue with Xcode 9 (Swift 3.2 or 4).

For easier migration of your code, follow these steps: (it will help you to covert into latest version of swift supported by your Xcode Tool)

(Xcode) Menus: Edit ► Covert ► To Current Swift Syntax

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