This is a simple change that is going to go a long way to help code readability. As you know, Swift developers prefer declaring things as constants (using let) rather than variables (using var). But what if you made something a variable by accident? Or if you thought you might need to change it, then never do?
As of Xcode 7 and Swift 2, you'll get warnings in your code whenever you declare variables that never change – Xcode literally examines the way you use the variable and knows if you never change it.
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Other changes in Swift 2.0…
- Throwing errors
- Use the guard keyword for early returns
- Measure strings using their character count
- Use the defer keyword to delay work until your scope exits
- Checking API availability
Download all Swift 2.0 changes as a playground Link to Swift 2.0 changes
