Annoying bool to string cast

php-implicit-type-cast.php

function foo(?string $val)
{
    echo (string) $val;
}

foo('test')
foo(true)
foo(false)
foo(null)

// Output: 
/*
array(2) {
  [0]=>
  string(6) "string"
  [1]=>
  string(4) "test"
}
array(2) {
  [0]=>
  string(6) "string"
  [1]=>
  string(1) "1"
}
array(2) {
  [0]=>
  string(6) "string"
  [1]=>
  string(0) ""
}
array(2) {
  [0]=>
  string(4) "NULL"
  [1]=>
  NULL
}
*/

// So true and false are getting casted to string. false will be empty, true will be 1
// SOLUTION: decalare strict types ....

declare(strict_types = 1);