k0nserv

@interface MyClass()
// Lazy inits are perfect for readonly values
// Note that strong can be used instead of copy here because
// we control the creation of the array and don't have to worry about
// being passed a mutable version
@property(nonatomic, readonly, strong) NSArray *values;
@end

@implementation MyClass

k0nserv

#import <Foundation/Foundation.h>

@interface Person
@property(nonatomic, copy) NSString *firstName;
@property(nonatomic, copy) NSString *lastName;
@property(nonatomic, readonly, strong) NSString *fullName
@end

k0nserv

def hours(open, close)
  (0..6).to_a.map do |x|
    {
      start: x * 24 + open,
      end: x * 24 + close
    }
  end
end

# Could be binary search

k0nserv

println("Before async")
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0)
, {
    println("async")
})
println("After async")

k0nserv

func _if(condition: BooleanType, action: () -> ()) {
  if condition {
    action()
  }
}

_if(1 < 2) {
  println("1 is less than 2")
}

k0nserv

func _if_without_if(condition: BooleanType, action: () -> ()) {
    // We fake the false case by using an empty closure, e.g a NOP
    let actions = [{}, action]

    // boolValue returns a Bool and we can abuse the fact that
    // hashValue of true is 1 and then hashValue of false is 0 to
    // get the correct closure to run
    actions[condition.boolValue.hashValue]()
}

k0nserv

func _while(condition: @autoclosure () -> BooleanType, action: () -> ()) {
  while condition() {
    action()
  }
}

var i = 0
_while(i < 10) {
  println("\(i)")
  i += 1

k0nserv

(function () {
  "use strict";
  
  // Code..
  
}());

k0nserv

func _while_without_while(condition: @autoclosure () -> BooleanType, 
                          action: () -> ()) {
                          
  var loop: () -> () = { $0 }
  loop = {
    // The condition is called each time to 
    // see if the loop should continue
    if condition() {
      // Then the acutal action is called
      action()

k0nserv

func unless(condition: BooleanType, action: () -> ()) {
  if condition.boolValue == false {
    action()
  }
}

var opt: Int? = 10
unless(opt == nil) {
  println("opt was non nil")
}