array_all() returns true, if the given
   callback returns true for all elements.
   Otherwise the function returns false.
  
   The function returns true, if callback returns
   true for all elements. Otherwise the function returns false.
  
Example #1 array_all() example
<?php
$array = [
    'a' => 'dog',
    'b' => 'cat',
    'c' => 'cow',
    'd' => 'duck',
    'e' => 'goose',
    'f' => 'elephant'
];
// Check, if all animal names are shorter than 12 letters.
var_dump(array_all($array, function (string $value) {
    return strlen($value) < 12;
}));
// Check, if all animal names are longer than 5 letters.
var_dump(array_all($array, function (string $value) {
    return strlen($value) > 5;
}));
// Check, if all array keys are strings.
var_dump(array_all($array, function (string $value, $key) {
   return is_string($key);
}));
?>The above example will output:
bool(true) bool(false) bool(true)