Just PHP FUN 052.

double_global_num.php

<?php
# https://www.codewars.com/kata/581a52d305fe7756720002eb PHP in Action #1 - Introduction to Superglobals [Fundamentals].
function double_global_num() {
  return $GLOBALS['num'] *= 2;
}
function set_query($query) {
  return $_GET['query'] = $query;
}
function set_email($email) {
  return $_POST['email'] = $email;
}

just_php_fun_052.md

Just PHP FUN 052.

• https://www.codewars.com/kata/58b63cb2b7d86adb650000b7 Simple Fun #173: A Hero Go To The School.
• https://www.codewars.com/kata/581a52d305fe7756720002eb Is that a real phone number? (British version).
• https://www.codewars.com/kata/581a52d305fe7756720002eb PHP in Action #1 - Introduction to Superglobals [Fundamentals].
• https://www.codewars.com/kata/57dbd9d68d7f5a785f00000f PHP Functions - The "Use" Keyword.
• https://www.codewars.com/kata/58a0697ef636cac09c000014 Youtube URL.

Started at 22:28 17.07.2020 Friday July.
Finished at 23:33 17.07.2020 Friday July. (1hr 05minutes)

makeYoutubeLink.php

<?php
# https://www.codewars.com/kata/58a0697ef636cac09c000014 Youtube URL.
<?php
# https://www.codewars.com/kata/581a52d305fe7756720002eb PHP in Action #1 - Introduction to Superglobals [Fundamentals].
function double_global_num() {
  return $GLOBALS['num'] *= 2;
}
function set_query($query) {
  return $_GET['query'] = $query;
}
function set_email($email) {
  return $_POST['email'] = $email;
}
function makeYoutubeLink(string $str): string {
  $prfx =
    [
    'https://www.youtube.com/embed/',
    'https://www.youtube.com/watch?v=',
    'http://www.youtube.com/watch?v=',
    'https://youtu.be/',
    'http://youtube.com/',
    'https://youtube.ru/watch?i='
  ];
  foreach($prfx as $x) if($z = sbst($str,$x)) return $z;
  throw new Exception("Incorrect input: $str \n");
}
function sbst($str,$prfx){
  if(0 === strpos($str,$prfx)) return 'https://www.youtube.com/embed/'.substr($str,strlen($prfx));
  return false;
}
// Exception: Incorrect input: http://youtube.com/UN8oLGBNXpE
// Exception: Incorrect input: https://youtube.ru/watch?i=YpEElOCPAeQ

multiple_closures.php

<?php
# https://www.codewars.com/kata/57dbd9d68d7f5a785f00000f PHP Functions - The "Use" Keyword. 
function multiple_closures($a){
  return function($b,$c) use ($a){
    return function ($d,$e) use ($a,$b,$c){
      return $a + $b * $c - $d/$e;
      
    };
  };
  
}

validateNumber.php

<?php
# https://www.codewars.com/kata/581a52d305fe7756720002eb Is that a real phone number? (British version).
function validateNumber($str){
  $s = str_replace('-','',$str);
  if(preg_match('/^(\+44|0)7[0-9]{9}$/',$s)) return 'In with a chance';
  return 'Plenty more fish in the sea';
}

which_bus_to_take.php

<?php
# https://www.codewars.com/kata/58b63cb2b7d86adb650000b7 Simple Fun #173: A Hero Go To The School.
function which_bus_to_take(array $buses_colors, array $going_to_school): int {
  $x = array_map(null, $buses_colors, $going_to_school);
  $red = null; $blue = null;
  foreach($x as $k => $v){
    if( is_null($red) && $v[1] && 'red' == $v[0] ) {$red = $k;}
    if( is_null($blue) && $v[1] && 'blue' == $v[0]) $blue = $k;
  }
  if(!is_null($red)) return $red;
  return $blue;
}