[swift-evolution] 3.0 if-var workaround construction question

[Joe Groff]

Yeah, declaring the `var` immediately inside the `if` block is equivalent to the deprecated `if var` form.

-Joe

> On Dec 17, 2015, at 10:32 AM, Erica Sadun via swift-evolution <swift-evolution at swift.org> wrote:
> 
> My new linter picked up the following as a problem for Swift 3.0, because of my interpretation of the rules in  https://github.com/apple/swift-evolution/blob/master/proposals/0003-remove-var-parameters-patterns.md <https://github.com/apple/swift-evolution/blob/master/proposals/0003-remove-var-parameters-patterns.md>
> 
>     if var testStream = OutputStream(path: aPath) {
>         print("Testing custom output", toStream: &testStream)
>         print("Hello ", terminator: "", toStream: &testStream)
>         print("World", toStream: &testStream)
>         print("Output sent to \(testStream.path)")
>     } else {
>         print("Failed to create custom output")
>     }
> 
> Am I right in assuming this construction will not compile in Swift 3.0? And if so, how should I best recommend re-configuration. I assume the preferred route would be either:
> 
>     if let outputStream = OutputStream(path: aPath) {
>         var testStream = outputStream
>         print("Testing custom output", toStream: &testStream)
>         print("Hello ", terminator: "", toStream: &testStream)
>         print("World", toStream: &testStream)
>         print("Output sent to \(testStream.path)")
>     } else {
>         print("Failed to create custom output")
>     }
> 
> Or using shadowing to mimics the "if let x = x" pattern that has become conventional:
> 
>     if let outputStream = OutputStream(path: aPath) {
>         var outputStream = outputStream
>         print("Testing custom output", toStream: &outputStream)
>         print("Hello ", terminator: "", toStream: &outputStream)
>         print("World", toStream: &outputStream)
>         print("Output sent to \(outputStream.path)")
>     } else {
>         print("Failed to create custom output")
>     }
> 
> Thanks in advance for insight.
> 
> -- E
> 
> 
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