PHP

• 2022.03.12

phpのラムダ式でタイプヒンティングの練習

<?php function main(): void { $sum1 = function (int $a, int $b): int { return $a + $b; }; $sum2 = fn(int $a, int $b): int => $a + $b; echo $sum1(3, 7) . PHP_EOL; echo $sum2(4, 7) . PHP_EOL; } main();

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<?php   function main(): void {     $sum1 = function (int $a, int $b): int {         return $a + $b;     };          $sum2 = fn(int $a, int $b): int => $a + $b;       echo $sum1(3, 7) . PHP_EOL;     echo $sum2(4, 7) . PHP_EOL; }   main();

10 11

1 2

10 11

• 2021.08.05

php7.4のアロー関数の練習

<?php $c = 10; $add = fn ($x) => $x + $c; $p = fn ($a) => print($a . "\n"); $runner = fn ($func, $arg) => $func($arg); $runner($p, $runner($add, 5));

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<?php   $c = 10; $add = fn ($x) => $x + $c; $p = fn ($a) => print($a . "\n"); $runner = fn ($func, $arg) => $func($arg); $runner($p, $runner($add, 5));

15

1

15

• 2021.03.25

phpで配列のランダムなキーを取得する関数getRandomIdx

<?php function getRandomIdx($all) { $idxMax = count($all) - 1; $idxRandom = random_int(0, $idxMax); return $idxRandom; } function getArr() { $a = []; for ($i = 0; $i < 47; $i++) { $a[] = ''; } return $a; } $times = 10000; $a = []; for ($i = 0; $i < $times; $i++) { $all = getArr(); $idx = getRandomIdx($all); if (isset($a[$idx])) { $a[$idx]++; } else { $a[$idx] = 1; } } ksort($a); print_r($a);

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<?php   function getRandomIdx($all) {   $idxMax = count($all) - 1;   $idxRandom = random_int(0, $idxMax);   return $idxRandom; }   function getArr() {   $a = [];   for ($i = 0; $i < 47; $i++) {     $a[] = '';   }   return $a; }   $times = 10000; $a = [];   for ($i = 0; $i < $times; $i++) {   $all = getArr();   $idx = getRandomIdx($all);     if (isset($a[$idx])) {     $a[$idx]++;   } else {     $a[$idx] = 1;   } }   ksort($a); print_r($a);

Array ( [0] => 203 [1] => 204 [2] => 225 [3] => 226 [4] => 189 [5] => 200 [6] => 219 [7] => 224 [8] => 207 [9] => 249 [10] => 195 [11] => 204 [12] => 223 [13] => 210 [14] => 210 [15] => 224 [16] => 224 [17] => 202 [18] => 203 [19] => 212 [20] => 222 [21] => 214 [22] => 207 [23] => 188 [24] => 221 [25] => 199 [26] => 249 [27] => 170 [28] => 193 [29] => 223 [30] => 210 [31] => 217 [32] => 206 [33] => 214 [34] => 232 [35] => 201 [36] => 200 [37] => 198 [38] => 237 [39] => 220 [40] => 229 [41] => 219 [42] => 212 [43] => 213 [44] => 210 [45] => 237 [46] => 206 )

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

Array (     [0] => 203     [1] => 204     [2] => 225     [3] => 226     [4] => 189     [5] => 200     [6] => 219     [7] => 224     [8] => 207     [9] => 249     [10] => 195     [11] => 204     [12] => 223     [13] => 210     [14] => 210     [15] => 224     [16] => 224     [17] => 202     [18] => 203     [19] => 212     [20] => 222     [21] => 214     [22] => 207     [23] => 188     [24] => 221     [25] => 199     [26] => 249     [27] => 170     [28] => 193     [29] => 223     [30] => 210     [31] => 217     [32] => 206     [33] => 214     [34] => 232     [35] => 201     [36] => 200     [37] => 198     [38] => 237     [39] => 220     [40] => 229     [41] => 219     [42] => 212     [43] => 213     [44] => 210     [45] => 237     [46] => 206 )

• 2021.02.26

cakephpでモデルにフィールドが無いformのエラーメッセージの出し方

password_confirm というフォームのエラーメッセージを出す方法。

// form.ctp echo $this->Form->control('password_confirm', ['type' => 'text']);

1 2	// form.ctp echo $this->Form->control('password_confirm', ['type' => 'text']);

// MemberController $entity->errors('password_confirm', '確認用パスワードが不一致です。');

1 2	// MemberController $entity->errors('password_confirm', '確認用パスワードが不一致です。');

• 2021.02.18

phpのポインタの変な挙動(再)

<?php $a = [0,1,2]; $unko = &$a[1]; $result = $a; foreach($a as &$v){ $v += 100; } print_r($result);

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<?php   $a = [0,1,2];   $unko = &$a[1];   $result = $a;   foreach($a as &$v){     $v += 100; }   print_r($result);

Array ( [0] => 0 [1] => 101 [2] => 2 )

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Array (     [0] => 0     [1] => 101     [2] => 2 )

• 2021.02.16

FizzBuzzをPHPで急いで書いた

<?php for($i=1; $i<=100; $i++){ if(0 === $i % 15){ echo 'FizzBuzz'; }elseif(0 === $i % 3){ echo 'Fizz'; }elseif(0 === $i % 5){ echo 'Buzz'; }else{ echo $i; } if(100 !== $i){ echo ','; } } // 1分45秒以内で書いた

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<?php   for($i=1; $i<=100; $i++){     if(0 === $i % 15){         echo 'FizzBuzz';     }elseif(0 === $i % 3){         echo 'Fizz';     }elseif(0 === $i % 5){         echo 'Buzz';     }else{         echo $i;     }     if(100 !== $i){         echo ',';     } } // 1分45秒以内で書いた

1,2,Fizz,4,Buzz,Fizz,7,8,Fizz,Buzz,11,Fizz,13,14,FizzBuzz,16,17,Fizz,19,Buzz,Fizz,22,23,Fizz,Buzz,26,Fizz,28,29,FizzBuzz,31,32,Fizz,34,Buzz,Fizz,37,38,Fizz,Buzz,41,Fizz,43,44,FizzBuzz,46,47,Fizz,49,Buzz,Fizz,52,53,Fizz,Buzz,56,Fizz,58,59,FizzBuzz,61,62,Fizz,64,Buzz,Fizz,67,68,Fizz,Buzz,71,Fizz,73,74,FizzBuzz,76,77,Fizz,79,Buzz,Fizz,82,83,Fizz,Buzz,86,Fizz,88,89,FizzBuzz,91,92,Fizz,94,Buzz,Fizz,97,98,Fizz,Buzz

1

1,2,Fizz,4,Buzz,Fizz,7,8,Fizz,Buzz,11,Fizz,13,14,FizzBuzz,16,17,Fizz,19,Buzz,Fizz,22,23,Fizz,Buzz,26,Fizz,28,29,FizzBuzz,31,32,Fizz,34,Buzz,Fizz,37,38,Fizz,Buzz,41,Fizz,43,44,FizzBuzz,46,47,Fizz,49,Buzz,Fizz,52,53,Fizz,Buzz,56,Fizz,58,59,FizzBuzz,61,62,Fizz,64,Buzz,Fizz,67,68,Fizz,Buzz,71,Fizz,73,74,FizzBuzz,76,77,Fizz,79,Buzz,Fizz,82,83,Fizz,Buzz,86,Fizz,88,89,FizzBuzz,91,92,Fizz,94,Buzz,Fizz,97,98,Fizz,Buzz

• 2020.12.20

phpでタイプヒンティングとコールバックの練習

<?php declare(strict_types=1); function test(callable $func): float { return 123 + $func(); } echo test(function () { return 456; });

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<?php   declare(strict_types=1);   function test(callable $func): float {   return 123 + $func(); }   echo test(function () {   return 456; });

579

1

579

• 2020.12.20

phpでマイクロ秒をミリ秒にして時間測定する

<?php $timeStartMicroSec = microtime(true); usleep(1000); //1000 マイクロ秒スリープする $timeEndMicroSec = microtime(true); $timeLapseMicroSec = $timeEndMicroSec - $timeStartMicroSec; $timeLapseMilliSec = $timeLapseMicroSec * 1000; $timeLapseMilliSecRounded = round($timeLapseMilliSec, 4); echo "{$timeLapseMilliSecRounded} ミリ秒";

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<?php   $timeStartMicroSec = microtime(true);   usleep(1000); //1000 マイクロ秒スリープする   $timeEndMicroSec = microtime(true);   $timeLapseMicroSec = $timeEndMicroSec - $timeStartMicroSec;   $timeLapseMilliSec = $timeLapseMicroSec * 1000;   $timeLapseMilliSecRounded = round($timeLapseMilliSec, 4);   echo "{$timeLapseMilliSecRounded} ミリ秒";

1.0641 ミリ秒

1	1.0641 ミリ秒

• 2020.08.16

12枚のコインがあるが一枚はニセモノで、重いか軽いかは分からない 天秤を3回だけ使ってどのコインがニセモノか特定せよ

<?php $tester = new Tester; $tester->testAndDisp(); class Tester { public function testAndDisp($times = 10000) { $result = $this->test($times); $msg = $result ? '成功' : '失敗'; echo $times . ' 回のテスト : ' . $msg; } public function test($times) { for ($i = 0; $i < $times; $i++) { if (false === $this->testOneTime()) { return false; } } return true; } private function testOneTime() { $solver = new Solver; $scales = new Scales; $coins = Coin::createCoinsForProbrem(); $result = $solver->solve($scales, $coins); $resultCoin = $result[0]; $resultLabel = $result[1]; if (($resultCoin->getWeight() < Coin::$weightBasic) && ($resultLabel === '軽い')) { return true; } if ((Coin::$weightBasic < $resultCoin->getWeight()) && ($resultLabel === '重い')) { return true; } return false; } } class Solver { public function solve($scales, $coins) { // 任意の4対4で測る(1回目) $result1 = $scales->scale( $this->pick($coins, 0, 1, 2, 3), $this->pick($coins, 4, 5, 6, 7) ); // 1. 傾いた時、重い側をabcd、軽い側をefghとし、abe対cdfで測る(2回目) if ($result1 !== 0) { if ($result1 === 1) { $a = $coins[0]; $b = $coins[1]; $c = $coins[2]; $d = $coins[3]; $e = $coins[4]; $f = $coins[5]; $g = $coins[6]; $h = $coins[7]; } else { $a = $coins[4]; $b = $coins[5]; $c = $coins[6]; $d = $coins[7]; $e = $coins[0]; $f = $coins[1]; $g = $coins[2]; $h = $coins[3]; } $result2 = $scales->scale( [$a, $b, $e], [$c, $d, $f] ); // 1-1. abe>cdfのとき、aとbのどちらかが重いもしくはfが軽いと分かるので、a対bで測る(3回目) // 1-1-1. a>bのとき、aが重いコイン // 1-1-2. a<bのとき、bが重いコイン // 1-1-3. a=bのとき、fが軽いコイン if ($result2 === 1) { $result3 = $scales->scale([$a], [$b]); switch ($result3) { case 1: return [$a, '重い']; case -1: return [$b, '重い']; case 0: return [$f, '軽い']; } } // 1-2. abe<cdfのとき、cとdのどちらかが軽いもしくはeが軽いと分かるので、c対dで測る(3回目) // 1-2-1. c>dのとき、cが重いコイン // 1-2-2. c<dのとき、dが重いコイン // 1-2-3. c=dのとき、eが軽いコイン else if ($result2 === -1) { $result3 = $scales->scale([$c], [$d]); switch ($result3) { case 1: return [$c, '重い']; case -1: return [$d, '重い']; case 0: return [$e, '軽い']; } } // 1-3. abe=cdfのとき、gとhのどちらかが軽いと分かるので、g対hで測る(3回目) // 1-3-1. g>hのとき、hが軽いコイン // 1-3-2. g<hのとき、gが軽いコイン else { $result3 = $scales->scale([$g], [$h]); switch ($result3) { case 1: return [$h, '軽い']; case -1: return [$g, '軽い']; } } } // 2. 釣り合った時、測った8枚をそれぞれo(重さが均一なコイン)、測らなかった4枚をijklとし、ij対koで測る(2回目) else { $o = $coins[0]; $i = $coins[8]; $j = $coins[9]; $k = $coins[10]; $l = $coins[11]; $result2 = $scales->scale( [$i, $j], [$k, $o] ); // 2-1. ij>koのとき、iとjのどちらかが重いもしくはkが軽いと分かるので、i対jで測る(3回目) // 2-1-1. i>jのとき、iが重いコイン // 2-1-2. i<jのとき、jが重いコイン // 2-1-3. i=jのとき、kが軽いコイン if ($result2 === 1) { $result3 = $scales->scale([$i], [$j]); switch ($result3) { case 1: return [$i, '重い']; case -1: return [$j, '重い']; case 0: return [$k, '軽い']; } } // 2-2. ij<koのとき、iとjのどちらかが軽いもしくはkが重いと分かるので、i対jで測る(3回目) // 2-2-1. i>jのとき、jが軽いコイン // 2-2-2. i<jのとき、iが軽いコイン // 2-2-3. i=jのとき、kが重いコイン else if ($result2 === -1) { $result3 = $scales->scale([$i], [$j]); switch ($result3) { case 1: return [$j, '軽い']; case -1: return [$i, '軽い']; case 0: return [$k, '重い']; } } // 2-3. ij=koのとき、lが重いもしくは軽いと分かるので、l対oで測る(3回目) // 2-3-1. l>oのとき、lが重いコイン // 2-3-2. l<oのとき、lが軽いコイン else { $result3 = $scales->scale([$l], [$o]); switch ($result3) { case 1: return [$l, '重い']; case -1: return [$l, '軽い']; } } } } private function pick($coins, ...$idxes) { $a = []; foreach ($idxes as $idx) { $a[] = $coins[$idx]; } return $a; } } class Scales { private $count = 0; private function countUp() { $this->count++; } public function getCount() { return $this->count; } public function scale($coinsA, $coinsB) { $this->countUp(); $totalWeightA = Coin::getTotalWeightOfCoins($coinsA); $totalWeightB = Coin::getTotalWeightOfCoins($coinsB); return ($totalWeightA <=> $totalWeightB); } } class Coin { protected $weight; public function __construct($weight) { $this->weight = $weight; } public function getWeight() { return $this->weight; } public static $weightBasic = 50; public static function createCoinsForProbrem() { $num = 12; $weightBasic = self::$weightBasic; $randomOffset = (random_int(0, 1) === 0) ? -1 : 1; $weightIrregular = $weightBasic + $randomOffset; $irregularIdx = random_int(0, $num - 1); $coins = []; for ($i = 0; $i < $num; $i++) { $weight = ($i === $irregularIdx) ? $weightIrregular : $weightBasic; $coins[] = new Coin($weight); } return $coins; } public static function getTotalWeightOfCoins($coins) { $totalWeight = 0; foreach ($coins as $coin) { $totalWeight += $coin->getWeight(); } return $totalWeight; } }

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<?php   $tester = new Tester; $tester->testAndDisp();   class Tester {   public function testAndDisp($times = 10000)   {     $result = $this->test($times);     $msg = $result ? '成功' : '失敗';     echo $times . ' 回のテスト : ' . $msg;   }   public function test($times)   {     for ($i = 0; $i < $times; $i++) {       if (false === $this->testOneTime()) {         return false;       }     }     return true;   }   private function testOneTime()   {     $solver = new Solver;     $scales = new Scales;     $coins = Coin::createCoinsForProbrem();       $result = $solver->solve($scales, $coins);     $resultCoin = $result[0];     $resultLabel = $result[1];       if (($resultCoin->getWeight() < Coin::$weightBasic) && ($resultLabel === '軽い')) {       return true;     }     if ((Coin::$weightBasic < $resultCoin->getWeight()) && ($resultLabel === '重い')) {       return true;     }     return false;   } }   class Solver {   public function solve($scales, $coins)   {     // 任意の4対4で測る(1回目)     $result1 = $scales->scale(       $this->pick($coins, 0, 1, 2, 3),       $this->pick($coins, 4, 5, 6, 7)     );     // 1. 傾いた時、重い側をabcd、軽い側をefghとし、abe対cdfで測る(2回目)     if ($result1 !== 0) {       if ($result1 === 1) {         $a = $coins[0];         $b = $coins[1];         $c = $coins[2];         $d = $coins[3];         $e = $coins[4];         $f = $coins[5];         $g = $coins[6];         $h = $coins[7];       } else {         $a = $coins[4];         $b = $coins[5];         $c = $coins[6];         $d = $coins[7];         $e = $coins[0];         $f = $coins[1];         $g = $coins[2];         $h = $coins[3];       }       $result2 = $scales->scale(         [$a, $b, $e],         [$c, $d, $f]       );       // 1-1. abe>cdfのとき、aとbのどちらかが重いもしくはfが軽いと分かるので、a対bで測る(3回目)       // 1-1-1. a>bのとき、aが重いコイン       // 1-1-2. a<bのとき、bが重いコイン       // 1-1-3. a=bのとき、fが軽いコイン       if ($result2 === 1) {         $result3 = $scales->scale([$a], [$b]);         switch ($result3) {           case 1:             return [$a, '重い'];           case -1:             return [$b, '重い'];           case 0:             return [$f, '軽い'];         }       }       // 1-2. abe<cdfのとき、cとdのどちらかが軽いもしくはeが軽いと分かるので、c対dで測る(3回目)       // 1-2-1. c>dのとき、cが重いコイン       // 1-2-2. c<dのとき、dが重いコイン       // 1-2-3. c=dのとき、eが軽いコイン       else if ($result2 === -1) {         $result3 = $scales->scale([$c], [$d]);         switch ($result3) {           case 1:             return [$c, '重い'];           case -1:             return [$d, '重い'];           case 0:             return [$e, '軽い'];         }       }       // 1-3. abe=cdfのとき、gとhのどちらかが軽いと分かるので、g対hで測る(3回目)       // 1-3-1. g>hのとき、hが軽いコイン       // 1-3-2. g<hのとき、gが軽いコイン       else {         $result3 = $scales->scale([$g], [$h]);         switch ($result3) {           case 1:             return [$h, '軽い'];           case -1:             return [$g, '軽い'];         }       }     }     // 2. 釣り合った時、測った8枚をそれぞれo(重さが均一なコイン)、測らなかった4枚をijklとし、ij対koで測る(2回目)     else {       $o = $coins[0];       $i = $coins[8];       $j = $coins[9];       $k = $coins[10];       $l = $coins[11];       $result2 = $scales->scale(         [$i, $j],         [$k, $o]       );       // 2-1. ij>koのとき、iとjのどちらかが重いもしくはkが軽いと分かるので、i対jで測る(3回目)       // 2-1-1. i>jのとき、iが重いコイン       // 2-1-2. i<jのとき、jが重いコイン       // 2-1-3. i=jのとき、kが軽いコイン       if ($result2 === 1) {         $result3 = $scales->scale([$i], [$j]);         switch ($result3) {           case 1:             return [$i, '重い'];           case -1:             return [$j, '重い'];           case 0:             return [$k, '軽い'];         }       }       // 2-2. ij<koのとき、iとjのどちらかが軽いもしくはkが重いと分かるので、i対jで測る(3回目)       // 2-2-1. i>jのとき、jが軽いコイン       // 2-2-2. i<jのとき、iが軽いコイン       // 2-2-3. i=jのとき、kが重いコイン       else if ($result2 === -1) {         $result3 = $scales->scale([$i], [$j]);         switch ($result3) {           case 1:             return [$j, '軽い'];           case -1:             return [$i, '軽い'];           case 0:             return [$k, '重い'];         }       }       // 2-3. ij=koのとき、lが重いもしくは軽いと分かるので、l対oで測る(3回目)       // 2-3-1. l>oのとき、lが重いコイン       // 2-3-2. l<oのとき、lが軽いコイン       else {         $result3 = $scales->scale([$l], [$o]);         switch ($result3) {           case 1:             return [$l, '重い'];           case -1:             return [$l, '軽い'];         }       }     }   }   private function pick($coins, ...$idxes)   {     $a = [];     foreach ($idxes as $idx) {       $a[] = $coins[$idx];     }     return $a;   } }   class Scales {   private $count = 0;   private function countUp()   {     $this->count++;   }   public function getCount()   {     return $this->count;   }   public function scale($coinsA, $coinsB)   {     $this->countUp();     $totalWeightA = Coin::getTotalWeightOfCoins($coinsA);     $totalWeightB = Coin::getTotalWeightOfCoins($coinsB);     return ($totalWeightA <=> $totalWeightB);   } }   class Coin {   protected $weight;   public function __construct($weight)   {     $this->weight = $weight;   }   public function getWeight()   {     return $this->weight;   }     public static $weightBasic = 50;   public static function createCoinsForProbrem()   {     $num = 12;     $weightBasic = self::$weightBasic;     $randomOffset = (random_int(0, 1) === 0) ? -1 : 1;     $weightIrregular = $weightBasic + $randomOffset;     $irregularIdx = random_int(0, $num - 1);     $coins = [];     for ($i = 0; $i < $num; $i++) {       $weight = ($i === $irregularIdx) ? $weightIrregular : $weightBasic;       $coins[] = new Coin($weight);     }     return $coins;   }   public static function getTotalWeightOfCoins($coins)   {     $totalWeight = 0;     foreach ($coins as $coin) {       $totalWeight += $coin->getWeight();     }     return $totalWeight;   } }

10000 回のテスト : 成功

1	10000 回のテスト : 成功

• 2020.08.05

PHPのtrait(トレイト)はreturn $thisが定義できる

<?php interface Cryable { public function cry(); } interface Movable { public function move(); } trait MoveGround { public function move() { echo 'トコトコ' . PHP_EOL; return $this; } } trait MoveAir { public function move() { echo 'ヒュー' . PHP_EOL; return $this; } } abstract class Animal implements Cryable, Movable { protected $age; public function __construct($age) { $this->age = $age; } } class Cat extends Animal { use MoveGround; public function cry() { echo "ニャー({$this->age})" . PHP_EOL; return $this; } } class Bird extends Animal { use MoveAir; public function cry() { echo "鳥です({$this->age})" . PHP_EOL; return $this; } } (new Cat(5))->cry()->move(); (new Bird(7))->move()->cry();

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<?php   interface Cryable {   public function cry(); }   interface Movable {   public function move(); }   trait MoveGround {   public function move()   {     echo 'トコトコ' . PHP_EOL;     return $this;   } }   trait MoveAir {   public function move()   {     echo 'ヒュー' . PHP_EOL;     return $this;   } }   abstract class Animal implements Cryable, Movable {   protected $age;   public function __construct($age)   {     $this->age = $age;   } }   class Cat extends Animal {   use MoveGround;   public function cry()   {     echo "ニャー({$this->age})" . PHP_EOL;     return $this;   } }   class Bird extends Animal {   use MoveAir;   public function cry()   {     echo "鳥です({$this->age})" . PHP_EOL;     return $this;   } }   (new Cat(5))->cry()->move(); (new Bird(7))->move()->cry();

ニャー(5) トコトコ ヒュー 鳥です(7)

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ニャー(5) トコトコ ヒュー 鳥です(7)