bklimt

void exampleA() {
  char a = 'A';
  ^{
    printf("%c\n", a);
  }();
}

bklimt

void exampleB_addBlockToArray(NSMutableArray *array) {
  char b = 'B';
  [array addObject:^{
    printf("%c\n", b);
  }];
}

void exampleB() {
  NSMutableArray *array = [NSMutableArray array];
  exampleB_addBlockToArray(array);

bklimt

void exampleC_addBlockToArray(NSMutableArray *array) {
  [array addObject:^{
    printf("C\n");
  }];
}

void exampleC() {
  NSMutableArray *array = [NSMutableArray array];
  exampleC_addBlockToArray(array);
  void (^block)() = [array objectAtIndex:0];

bklimt

typedef void (^dBlock)();

dBlock exampleD_getBlock() {
  char d = 'D';
  return ^{
    printf("%c\n", d);
  };
}

void exampleD() {

bklimt

typedef void (^eBlock)();

eBlock exampleE_getBlock() {
  char e = 'E';
  void (^block)() = ^{
    printf("%c\n", e);
  };
  return block;
}

bklimt

/**
 * Adapted from http://folklore.org/projects/Macintosh/more/BootBeep.txt
 * A direct translation of the m68k asm into JavaScript.
 * @returns {Buffer} a Buffer which  corresponds to the audio buffer on the
 * original Macintosh, repeated for the duration of the boot beep. The Buffer
 * contains a series of words, where the lower byte of each word is the
 * amplitude of the audio signal at this point.
 */
var bootbeepASM = function() {
  d3 = 40;  // D3 contains the duration: 40 is boot beep

bklimt

/**
 * Lets you fill a Buffer without having to know its size beforehand.
 */
var BufferWriter = function() {
  this._size = 0;
  this._buffer = new Buffer(100);
};

_.extend(BufferWriter.prototype, {
  buffer: function() {

bklimt

/**
 * Creates a helper to write a WAVE file to a Buffer.
 * @param {Number} seconds - The length of the WAVE file to write.
 * @param {Number} sampleRate - The sample rate in Hz, such as 44100 for a CD.
 * @param {Number} bitsPerSample - Either 8 or 16.
 */
var WaveWriter = function(seconds, sampleRate, bitsPerSample) {
  this._sampleRate = sampleRate;
  this._bitsPerSample = bitsPerSample;
  this._writer = new BufferWriter();

bklimt

var sineWave = function(frequency) {
  var writer = new WaveWriter(2.0, 11025, 8);
  var time = 0;
  var sample = 0;
  do {
    sample = Math.sin(frequency * time * 2 * 3.14159);
    time = time + 1/11025;
  } while (writer.writeSample(sample));
  writer.close();
  return writer.buffer();

bklimt

/**
 * Runs the bootbeepASM methods and then converts the audio data to a WAVE file.
 * @returns {Buffer} a Buffer containing the contents of a WAVE file.
 */
var bootbeep = function() {
  // 22050 Hz is an approximation of the Mac's 370 * 60.15 Hz = 22255.5 Hz.
  var writer = new WaveWriter(1.5, 22050, 8);
  var samples = bootbeepASM();
  console.log("Copying samples to WAVE.");
  var i = 0;