http://ericasadun.com/2015/11/24/wrapping-and-indentation-opinions/ response

wrapping-and-indentation-opinions.swift

enum StringPaddingStyle {case Left, Right}

func padStringToLength(
   sourceString: String,
   destinationCount: Int,
   paddingStyle: StringPaddingStyle = .Left,
   paddingCharacter: Character = " "
) -> String {
   let padCount = destinationCount - sourceString.characters.count,
      padString = String(count: padCount, repeatedValue: paddingCharacter)
   return paddingStyle == .Left ? padString + sourceString
      : sourceString + padString
}

func elongatedToShowRationaleForShortcuts(
   sourceString: String,
   destinationCount: Int,
   paddingStyle: StringPaddingStyle = .Left,
   paddingCharacter: Character = " "
) -> String {
   let standsAlone = ""
   let
      standsAlone1 = "",
      standsAlone2 = "",
      standsAlone3 = ""
   let isUsedAgainInThisList = "",
   
      reliesOnIsUsedInThisList = isUsedAgainInThisList,
      andThisAlsoRelies = isUsedAgainInThisList
   
   let padCount = destinationCount - sourceString.characters.count,
      padString = String(count: padCount, repeatedValue: paddingCharacter)
   return {
      if paddingStyle == .Left {return padString + sourceString}
      else {return sourceString + padString}
   }()
}

"CURRY" is actually the curry emoji, but Gist comments don't support emoji. Actual code is here: https://github.com/Jessy-/Euler/blob/master/Euler_Metal/EulerProblem.swift
I think adding an empty line after the constants upon which others depend is good, unless only one constant is dependent:

let commandBuffer = commandQueue.commandBuffer(),
   commandEncoder = commandBuffer.computeCommandEncoder()

I thought that I had a good example of how I've used more dependent "combined lets"…

compute = {
   let device = MTLCreateSystemDefaultDevice()!,

      commandQueue = device.newCommandQueue(),
      pipelineState = try! device.newComputePipelineStateWithFunction(
         device.newDefaultLibrary()!.newFunctionWithName(functionName)!
      ),
      sumBuffer = device.newBufferWithLength(4, options: .CPUCacheModeDefaultCache)

   return computeCURRY(
      commandQueue: commandQueue,
      pipelineState: pipelineState,
      sumBuffer: sumBuffer
   )
}()

...but I actually do it like this now:

compute = {
   let device = MTLCreateSystemDefaultDevice()!
   return computeCURRY(
      commandQueue: device.newCommandQueue(),
      pipelineState: try! device.newComputePipelineStateWithFunction(
         device.newDefaultLibrary()!.newFunctionWithName(functionName)!
      ),
      sumBuffer: device.newBufferWithLength(4, options: .CPUCacheModeDefaultCache)
   )
}()

There is consistency in how far in those parameter or constant names are indented, though.