制約でコードに秩序を

2016/05/21 PHP カンファレンス福岡 2016

Transcript

1. ɹ!shin1x1 2016/05/21 1)1ΧϯϑΝϨϯε෱Ԭ
    ੍໿ͰίʔυʹடংΛ
2. ੍໿ͱ͸
3. ੍ݶ΍৚݅Λ͚ͭͯ
   ࣗ༝ʹ׆ಈͤ͞ͳ͍͜ͱ https://kotobank.jp/word/%E5%88%B6%E7%B4%84-546519
4. ੍ݶ΍৚݅Λ͚ͭͯ
   ࣗ༝ʹ׆ಈͤ͞ͳ͍͜ͱ https://kotobank.jp/word/%E5%88%B6%E7%B4%84-546519
5. ࠓ೔ͷ୊ࡐ
6. &$αΠτ
   γϣοϐϯάΧʔτ
7. Χʔτʹ௥Ճ
8. ΧʔτΛදࣔ
9. <DBTF>
   Χʔτʹ঎඼Λ௥Ճ
10. D
    
    .BTBTIJ
    4IJOCBSB
    !TIJOY Χʔτʹ঎඼Λ௥Ճ w
    Χʔτ
    
    $BSU
    Ϋϥε
    w
    ঎඼
    
    *UFN
    Ϋϥε
    
    w
    $BSUJUFNT
    ʹ঎඼Λ௥Ճ
11. *UFN class Item
 {
 public $code;
 public $price;
 
 public function __construct(string $code, int $price)
 {
 $this->code = $code;
 $this->price = $price;
 }
 }
12. $BSU class Cart
 {
 public $items;
 
 public function __construct()
 {
 $this->items = [];
 }
 
 public function calculateTotalPrice(): int
 {
 $totalPrice = 0;
 
 foreach ($this->items as $item) {
 $totalPrice = $totalPrice + $item->price;
 }
 
 return $totalPrice;
 }
 }
13. D
    
    .BTBTIJ
    4IJOCBSB
    !TIJOY ঎඼௥ՃΛ*UFNΫϥεʹݶఆ w
    $BSUJUFNT
    Λ
    QSJWBUF
    ͰӅ͢
    w
    BEE*UFNϝιουΛ௥Ճ
    w
    λΠϓώϯςΟϯάͰ
    *UFN
    Ϋϥεʹݶఆ
14. $BSU class Cart
 {
 private $items;
 
 public function __construct()
 {
 $this->items = [];
 }
 
 public function addItem(Item $item)
 {
 $this->items[] = $item;
 }
 (snip) } QSJWBUF λΠϓώϯςΟϯά
15. D
    
    .BTBTIJ
    4IJOCBSB
    !TIJOY ΞΫηεम০ࢠ
    
    λΠϓώϯςΟϯά w
    Ϋϥεࣗ਎͕ϓϩύςΟΛίϯτϩʔϧ
    w
    Ϋϥε֎ʹίϯτϩʔϧΛ౉͞ͳ͍
    w
    ૢ࡞ํ๏Λݶఆ͍ͯ͠Δ͔Βͦ͜

    
    
    ίϯτϩʔϧͰ͖Δ

    ʢλΠϓώϯςΟϯάͳͲʣ
16. <DBTF>
    Χʔτͷ঎඼఺਺͸
    ఺·Ͱ
17. D
    
    .BTBTIJ
    4IJOCBSB
    !TIJOY Χʔτͷ঎඼఺਺͸఺Ҏ಺ w
    ఺Ҏ্ͷ঎඼Λ֨ೲ͠Α͏ͱͨ͠Βྫ֎ൃੜ
    w
    ঎඼௥ՃͷࡍʹνΣοΫΛߦ͏
18. D
    
    .BTBTIJ
    4IJOCBSB
    !TIJOY BEE*UFNϝιουͰ੍໿ w
    BEE*UFNϝιουͰ঎඼఺਺ΛνΣοΫ
    w
    ͜ͷϝιουͰ͔͠$BSUJUFNTΛ

    
    
    มߋͰ͖ͳ͍ͷͰ༗ޮ
    w
    ϓϩύςΟͷίϯτϩʔϧΛΫϥεࣗ਎͕ߦ͏

    
    
    
    QVCMJD
    ͩͱ֎෦ʹίϯτϩʔϧ͞ΕΔ
19. $BSU class Cart
 { (snip)
 public function addItem(Item $item)
 {
 if (count($this->items) >= 3) {
 throw new PreconditionException();
 }
 
 $this->items[] = $item;
 } (snip)
 }
20. <DBTF>
    ঎඼খܭʹ
    ফඅ੫ΛՃࢉ
21. D
    
    .BTBTIJ
    4IJOCBSB
    !TIJOY ੫ࠐՁ֨ࢉग़ w
    Χʔτͷ঎඼ͦΕͧΕʹফඅ੫ΛՃࢉ
    w
    ੫ࠐΈՁ֨ͷ߹ܭΛখܭՁ֨ͱ͢Δ
22. $BSU $cart = new Cart();
 
 $item1 = new Item('code1', 100);
 $cart->addItem($item1);
 
 $item2 = new Item('code2', 200);
 $cart->addItem($item2);
 
 $this->assertEquals(324, $cart->calculateTotalPrice());
 $this->assertEquals(324, $cart->calculateTotalPrice()); ʹͳΔʁʁʁ
23. $BSU class Cart
 { (snip)
 public function calculateTotalPrice(): int
 {
 $totalPrice = 0;
 
 foreach ($this->items as $item) {
 $item->price = (int)($item->price * 1.08);
 $totalPrice = $totalPrice + $item->price;
 }
 
 return $totalPrice;
 } (snip)
 } *UFNQSJDF͕
    มߋ͞ΕΔ ճݺͿͱ
    ͞Βʹ
    
    ഒʹͳΔ
24. D
    
    .BTBTIJ
    4IJOCBSB
    !TIJOY *UFNΫϥεΛෆมʹ͢Δ w
    ׬શίϯετϥΫλ

    
    
    
    ίϯετϥΫλͰશͯͷ஋Λ༩͑Δ
    w
    ෆมʢΠϛϡʔλϒϧʣΫϥε

    
    
    
    QSJDF
    ͸ৗʹಉ͡஋Λฦ͢
    w
    ඞཁͳHFUUFSͷΈ࣮૷
25. *UFN class Item
 {
 private $code;
 private $price;
 
 public function __construct(string $code, int $price)
 {
 $this->code = $code;
 $this->price = $price;
 }
 
 public function price(): int
 {
 return $this->price;
 }
 } QSJWBUF
26. $BSU class Cart
 { (snip)
 public function calculateTotalPrice(): int
 {
 $totalPrice = 0;
 
 foreach ($this->items as $item) {
 $price = (int)($item->price() * 1.08);
 $totalPrice = $totalPrice + $price;
 }
 
 return $totalPrice;
 } (snip)
 } *UFNQSJDF͸
    มߋͰ͖ͳ͍
27. <DBTF>
    Ձ֨΁ͷૢ࡞Λݶఆ
28. D
    
    .BTBTIJ
    4IJOCBSB
    !TIJOY Ձ֨ͷԋࢉΛ੍ݶ w
    JOU
    ͩͱҙຯ͕޿͗͢ΔʢՄೳͳԋࢉ΋ଟ͍ʣ
    w
    ଍͠ࢉͱ੫ࠐՁ֨ܭࢉʢֻ͚ࢉͰ͸ͳ͍ʣͷΈ
    w
    Ձ֨Λ1SJDFΫϥεͰදݱ
29. 1SJDF class Price
 {
 const TAX_RATE = 1.08;
 private $price;
 
 public function __construct(int $price)
 {
 $this->price = $price;
 }
 
 public function add(self $price): self
 {
 return new self($this->price + $price->price);
 }
 
 public function withTax(): self
 {
 return new self((int)($this->price * static::TAX_RATE));
 }
 
 public function toInt(): int
 {
 return $this->price;
 }
 }
30. *UFN class Item
 {
 private $code;
 private $price;
 
 public function __construct(string $code, int $price)
 {
 $this->code = $code;
 $this->price = new Price($price);
 }
 
 public function price(): Price
 {
 return $this->price;
 }
 }
31. $BSU class Cart
 { (snip)
 public function calculateTotalPrice(): Price
 {
 $totalPrice = new Price(0);
 
 foreach ($this->items as $item) {
 $price = $item->price()->withTax();
 $totalPrice = $totalPrice->add($price);
 }
 
 return $totalPrice;
 } (snip)
 } Ձ֨͸1SJDFͰදݱ ੫ࠐՁ֨ࢉग़ Ձ֨ͷ଍͠ࢉ
32. D
    
    .BTBTIJ
    4IJOCBSB
    !TIJOY 7BMVF0CKFDU w
    ஋ΛΫϥεͰදݱ
    w
    ෆมΫϥε

    
    
    
    ԋࢉ݁Ռ͸৽͍͠ΠϯελϯεͰฦ͢
    w
    ඞཁͳԋࢉͷΈΛ࣮૷
    w
    ಺෦ͷ஋ΛӅณ
33. <DBTF>
    ঎඼ɺΧʔτ৘ใΛ
    +40/Ͱग़ྗ
34. D
    
    .BTBTIJ
    4IJOCBSB
    !TIJOY ঎඼ɺΧʔτ৘ใΛ+40/Ͱग़ྗ w
    +BWB4DSJQUΫϥΠΞϯτ΍

    
    
    εϚʔτϑΥϯΞϓϦ࿈ܞ
    w
    *UFNUP"SSBZ Ͱ഑ྻͱͯ͠ग़ྗ
    w
    KTPO@FODPEF Ͱ+40/ʹ͢Δ
35. "QJ$POUSPMMFS class ApiController
 {
 public function item()
 {
 $item = new Item('code1', 100);
 $this->json($item);
 }
 
 private function json(Item $entity)
 {
 header('Content-Type: application/json');
 echo json_encode($entity->toArray());
 }
 }
36. class ApiController
 {
 public function item()
 {
 $item = new Item('code1', 100);
 $this->json($item);
 }
 public function cart()
 {
 $cart = new Cart();
 $cart->addItem(new Item('code1', 100));
 $cart->addItem(new Item('code2', 200));
 
 $this->json($cart);
 } private function json(Item $entity)
 {
 header('Content-Type: application/json');
 echo json_encode($entity->toArray());
 }
 } DBSU͸
 *UFNΫϥεͰ͸ͳ͍
37. D
    
    .BTBTIJ
    4IJOCBSB
    !TIJOY "SSBZBCMFΠϯλʔϑΣΠε w
    "QJ$POUSPMMFSKTPO ͕

    
    
    ඞཁͳґଘΛΠϯλʔϑΣΠεͰ໌ࣔ
    w
    ΠϯλʔϑΣΠε࣮͑͞૷͍ͯ͠Ε͹

    
    
    ͲΜͳΫϥεͰ΋ྑ͍
    w
    ࢓༷ͱ࣮૷ͷ෼཭
38. "SSBZBCMF interface Arrayable
 {
 public function toArray(): array;
 }
39. *UFN class Item implements Arrayable
 {
 (snip) public function toArray(): array
 {
 return [
 'code' => $this->code,
 'price' => $this->price->toInt(),
 ];
 }
 }
40. $BSU class Cart implements Arrayable
 {
 (snip) public function toArray(): array
 {
 return array_map(function (Item $item) {
 return $item->toArray();
 }, $this->items);
 }
 }
41. class ApiController
 {
 public function item()
 {
 $item = new Item('code1', 100);
 $this->json($item);
 }
 public function cart()
 {
 $cart = new Cart();
 $cart->addItem(new Item('code1', 100));
 $cart->addItem(new Item('code2', 200));
 
 $this->json($cart);
 } private function json(Arryable $entity)
 {
 header('Content-Type: application/json');
 echo json_encode($entity->toArray());
 }
 } "SSBZBCMF
42. D
    
    .BTBTIJ
    4IJOCBSB
    !TIJOY ˞ิ଍
    1)1
    ʹ͸ɺ+TPO4FSJBMJ[BCMF
    ͱ͍͏

    ΠϯλʔϑΣΠε͕͋Γ·͢ɻ

    ΦϒδΣΫτΛ
    +40/
    Խ͢Δࡍ͸

    ࢀߟʹ͍ͯͩ͘͠͞ɻ http://php.net/manual/ja/class.jsonserializable.php
43. ੍໿ͱ͸
44. ࣗ༝Λୣ͏
    ໘౗ͳ΋ͷͰ͸ͳ͘
45. டংΛकΓ
    ҙਤΛ໌֬ʹ͢Δ΋ͷ ੍໿ ΘΜͺ͘ͳίʔυ https://flic.kr/p/4e5ggf ίʔυͷடংΛ
    कΔ΋ͷ
46. ੍໿Ͱடং͋Δ։ൃΛʂ
47. D
    
    .BTBTIJ
    4IJOCBSB
    !TIJOY !TIJOY !TIJOY D
    
    .BTBTIJ
    4IJOCBSB
    !TIJOY
48. D
    
    .BTBTIJ
    4IJOCBSB
    !TIJOY QSPUFDUFE
    PS
    QSJWBUF w
    ·ͣ͸ɺQSJWBUF
    
    ඞཁͳΒ
    QSPUFDUFE
    w
    ͍͔ͭݺ͹ΕΔ͔΋͠Εͳ͍͔Β
    QSPUFDUFE

    
    
    
    :"(/*ʢ:PV
    BJOU
    HPOOB
    OFFE
    JUʣ
    w
    ଞਓ͕࡞ͬͨγεςϜΛϝϯςφϯε͢Δͱ

    
    
    QSJWBUF
    ສࡀʹͳΔ
    w
    USBJU͕͋ΔͷͰɺػೳͷͨΊʹܧঝ͢Δඞཁ͕ແ͍