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import Accelerate

func spectrumForValues(signal: [Double]) -> [Double] {
  // Find the largest power of two in our samples
  let log2N = vDSP_Length(log2(Double(signal.count)))
  let n = 1 << log2N
  let fftLength = n / 2

  // This is expensive; factor it out if you need to call this function a lot
  let fftsetup = create_fftsetupD(log2N, FFTRadix(kFFTRadix2))

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// Try this in a commandline app vs a playground. The behaviors are different.

class MyClass {
  func doSomething() {
    refresh() // I wonder which refresh we'll get?
  }
}

// Not only does this change the behavior of doSomething()... (see below)
// extension MyClass {

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// MyClass.swift

class MyClass {
  func doSomething() {
    refresh()
  }
}

private func refresh() {
  println("I'm the global refresh function.")

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func ==<A:Equatable, B:Equatable>(lhs:(A,B), rhs:(A,B)) -> Bool {
  return lhs.0 == rhs.0
    && lhs.1 == rhs.1
}

func ==<A:Equatable, B:Equatable, C:Equatable>(lhs:(A,B,C), rhs:(A,B,C)) -> Bool {
  return lhs.0 == rhs.0
    && lhs.1 == rhs.1
    && lhs.2 == rhs.2
}

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//
//  FFT.swift
//  Signal
//
//  Created by Rob Napier on 7/24/14.
//  Copyright (c) 2014 Rob Napier. All rights reserved.
//

import Accelerate

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// You call this as:
//   withExtendedLifetimes([x,y,z]) { ... }
// I haven't been able to replace the array with variadic. The function
// will be absorbed into the list (even if it's curried).
func withExtendedLifetimes(args: [Any], f: () -> ()) {
  var rest = args
  let last:Any = rest.removeLast()
  if rest.count > 0 {
    Swift.withExtendedLifetime(last) { () -> () in withExtendedLifetimes(rest, f) }
  }

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func reverseR<T>(result: [T], curList: Slice<T>) -> [T] {
  switch curList.first {
  case .None: return result
  case .Some(let cur): return reverseR([cur] + result, dropFirst(curList))
  }
}

func reverseTailRecursive<T>(ls: [T]) -> [T] {
  return reverseR([], Slice(ls))
}

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// Creating a generic recursive data structure with autoclosure. (READ ALL NOTES; THIS MAY NOT DO WHAT YOU WANT.)
// Closures are reference types, so the size is known (? I think ?)
// Note that this is just because of unimplemented features in the compiler in Beta5
// There's no reason to think this is a long-term requirement.

// IMPORTANT: the closure will run every time you access this value, so if that has
// side effects, this won't work. It's only possible on pure value types.

// But the fact that this works as expected is actually kind of incredible.
// Think about what is required for it to work out the type for NestedList.Elem("first").

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//
// Version 2 of pagesFromData from Functional Wish Fulfillment
// http://robnapier.net/functional-wish-fulfillment
//

import Foundation

func pagesFromData(data: NSData) -> Result<[Page]> {

  // 1. Parse the NSData into a JSON object

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//
// Version 1 of pagesFromData from Functional Wish Fulfillment
// http://robnapier.net/functional-wish-fulfillment
//

import Foundation

func pagesFromData(data: NSData) -> PageListResult {

  // 1. Parse the NSData into a JSON object