Obtaining Closure with Anonymous Functions

PHP Functional Programming using Functions, Lambdas, Anonymous Functions, and Closures.

Transcript

1. Obtaining Closure with Anonymous Functions @alc277
2. Functions&! Lambdas&! Anonymous&! Closures&! Fun.
3. Named Functions
4. Named Functions
5. Functions&! Lambdas&! Anonymous&! Closures&! Fun.
6. NAMED LAMBDA
7. Lambda Functions
9. Lambda Functions
10. Lambda Functions
11. Type Hinting
12. Wow much useful such amaze ! very programmer
13. Functions&! Lambdas&! Anonymous&! Closures&! Fun.
15. Anonymous Functions
16. Functions&! Lambdas&! Anonymous&! Closures&! Fun.
17. λ Closures Rasmus’s Throne Room
19. Lambda Variable Scope
20. Closure Variable Scope & “use”
21. Tricky Bit
22. Passing a Variable to a Lambda or Closure
24. Passing a Variable by Reference to a Lambda or Closure
27. Closure Class
28. Closure! {! ! /* Methods */! ! public bindTo () { }! ! ! ! ! ! ! ! } PHP Closure Class ! ! ! ! public static bind () {}! ! ! ** double-secret function __invoke() { }! !
30. Reasons to use Closures • Variable Scope and Binding! • Don’t Pollute Namespace With Functions! • Map/Reduce/Filter! • Data Output! • Retrieving Records from Database
31. • Currying! • Fixed-point Combinators (Y- Combinator)! • Improved Performance (Memoization)! • Monads! • Dependency Injection Reasons to use Closures
32. Things to Avoid • create_function! • Closure::bind()
33. Map/Reduce/Filter
34. Map/Reduce/Filter with Lambda Credit: Fabien Potencier
35. Map/Reduce/Filter Credit: Fabien Potencier Map/Reduce/Filter with Closure
36. Currying Photo: Penn State Office of Research Communications.
37. Currying
38. DATA OUTPUT
39. Data Output
40. Data Output
41. Database Records
42. Data Output
43. Y-Combinator
44. Y-Combinator
45. Y-Combinator
47. Memoization
48. fib(5) = fib(3) + fib(4)! fib(3) = fib(1) + fib(2)! fib(1) = 1! fib(2) = fib(1) + fib(0)! fib(1) = 1! fib(0) = 0! fib(2) = 1 + 0 = 1! fib(3) = 1 + 1 = 2! fib(4) = fib(3) + fib(2)! fib(3) = fib(1) + fib(2)! fib(1) = 1! fib(2) = fib(1) + fib(0)! fib(1) = 1! fib(0) = 0! fib(2) = 1 + 0 = 1! fib(3) = 1 + 1 = 2! fib(2) = fib(1) + fib(0)! fib(1) = 1! fib(0) = 0! fib(2) = 1 + 0 = 1! fib(4) = 2 + 1 = 3! fib(5) = 3 + 2 = 5
49. Memoization
50. 1 1 2 1 3 2 4 3 5 5 6 8 7 13 8 21 9 34 10 55 11 89 12 144 13 233 14 377 15 610 16 987
51. Memoization
53. Monads
54. MonadPHP Anthony Ferrara
55. Monads Credit: Anthony Ferrara
56. Monads Credit: Anthony Ferrara
57. Monads Credit: Anthony Ferrara
58. $posts = [! [“title" => "foo", "author" => [“name" => "Bob", "email" => “bob@example.com”]],! [“title" => "bar", "author" => array("name" => "Tom", "email" => “tom@example.com”]],! [“title" => “baz"],! [“title" => "biz", "author" => array("name" => "Mark", "email" => “mark@example.com”]],! ]; Monads Credit: Anthony Ferrara
59. Monads Credit: Anthony Ferrara
60. Dependency! Injection
61. Dependency Injection
62. Dependency Injection
63. Dependency Injection
64. Dependency Injection
65. Dependency Injection