Question

function test($str) {
  $c = count($str);
  if ($c>1) {
    foreach ($str as $key => $value) $result .= test($value);
  } else {
    $result = "<li>$str</li>\n";
  }
  echo $result ? "<ol>$result</ol>" : null;
}

The $str value could be either, something like this;

$str1 = "apple";

or something like that;

$str2 = array("apple","orange","pear");

If count($str) is more than one, which is $str is is_array, it repeats the $result.
But it doesn’t work as I want..
I get an error “Cannot redeclare test() (previously declared in…”

The ideal output would be – $str1;

<ol>
  <li>apple</li>
</ol>

The ideal output would be – $str2;

<ol>
  <li>apple</li>
  <li>orange</li>
  <li>pear</li>
</ol>

Answer 1

Check, if $str is an array, e.g.:

function test($str, $first=true) {
  if (!is_array($str)) {
    $result = "<li>$str</li>\n";
  } else {
    foreach ($str as $key => $value) $result .= test($value, false);
  }
  return ($first ? "<ol>$result</ol>" : $result);
}

Also see this example.

=== UPDATE ===

If you want to let it print directly, replace with:

function test($str, $first=true) {
  if (!is_array($str)) $result = "<li>$str</li>";
  else foreach ($str as $key => $value) $result .= test($value, false);
  if ($first) echo "<ol>$result</ol>";
  else return $result;
}

Also see this example.