Online PHP editor | output for tRCEs

@ 2015-10-02T11:25:16Z

<?php

$utf8_str = "\xf0\x9f\x92\xa9";
$ret    = '';
		$length = mb_strlen($utf8_str, 'UTF-8');
		for ($i = 0; $i < $length; $i++) {
			$char = mb_substr($utf8_str, $i, 1, 'UTF-8');
			$l    = strlen($char);
			if ($l <= 3) {
				$ret .= $char;
			} elseif ($l === 4) {
				$ret .= self::convert_char_to_cesu8($char);
			}// UTF-8で5文字以上になる文字はUnicodeとして不正なので無視（除去する）
		}

		$unko =  $ret;
var_dump($unko);
$encode = json_encode($unko);
var_dump($encode);

Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6: Fatal error: Uncaught Error: Cannot access "self" when no class scope is active in /in/tRCEs:12 Stack trace: #0 {main} thrown in /in/tRCEs on line 12
Process exited with code 255.
Output for 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33: Fatal error: Uncaught Error: Cannot access self:: when no class scope is active in /in/tRCEs:12 Stack trace: #0 {main} thrown in /in/tRCEs on line 12
Process exited with code 255.
Output for 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40: Fatal error: Cannot access self:: when no class scope is active in /in/tRCEs on line 12
Process exited with code 255.

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