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<?php if (!function_exists('json_encode')) { function json_encode($it) { if (!($assoc = is_object($it)) && !is_array($it)) { return _js_enc_value($it); } $i = 0; $it = (array)$it; if (!$assoc) { foreach ($it as $k => $v) { if ($k !== $i) { $assoc = true; break; } $i++; } } $data = array(); foreach ($it as $k => $v) { $v = _js_enc_value($v); if ($assoc) { $k = '"'. addcslashes($k, '"\\') . '"'; $data[] = $k . ':' . $v; } else { $data[] = $v; } } if ($assoc) { $spl = '{'; $spr = '}'; } else { $spl = '['; $spr = ']'; } return $spl . implode(',', $data) . $spr; } function _js_enc_value($value) { switch (true) { case is_array($value): case is_object($value): return json_encode($value); case is_bool($value): return $value ? 'true' : 'false'; case $value === null: case is_resource($value) && _js_error(): return 'null'; case is_string($value): return '"' . _js_uc_esc($value) . '"'; default: return $value; } } function _js_error() { return trigger_error('json_encode(): type is unsupported, encoded as null', E_USER_WARNING); } function _js_uc_esc($value) { $pattern = "/\r|(\n)|((?:[^\x09\x0A\x0D\x20-\x7E]{3})+)/"; return preg_replace_callback($pattern, '_js_uc_esc_cb', $value); } function _js_uc_esc_cb($matches) { switch (true) { case isset($matches[2]): $char = mb_convert_encoding($matches[2], 'UTF-16', 'UTF-8'); $str = ''; $len = strlen($char); for ($i = 0; $i < $len; $i += 2) { $str .= sprintf('\\u%02x%02x', ord($char[$i]), ord($char[$i + 1])); } return $str; case isset($matches[1]): return '\\n'; default: return '\\r'; } } } echo json_encode(array('<'));
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.10, 7.2.0 - 7.2.33, 7.3.12 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
["<"]

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235.08 ms | 405 KiB | 348 Q