syntax error, unexpected '=>' (T_DOUBLE_ARROW)

ParseError: syntax error, unexpected '=>' (T_DOUBLE_ARROW) in /www/wwwroot/xiamp.net/usr/plugins/AAEditor/HyperDown.php:1089 Stack trace: #0 [internal function]: Typecho\{closure}() #1 /www/wwwroot/xiamp.net/usr/plugins/AAEditor/Util.php(1474): spl_autoload_call() #2 [internal function]: TypechoPlugin\AAEditor\Util::markdown() #3 /www/wwwroot/xiamp.net/var/Typecho/Plugin.php(446): call_user_func_array() #4 /www/wwwroot/xiamp.net/var/Widget/Base/Contents.php(914): Typecho\Plugin->__call() #5 /www/wwwroot/xiamp.net/var/Widget/Base/Contents.php(960): Widget\Base\Contents->markdown() #6 /www/wwwroot/xiamp.net/var/Typecho/Widget.php(395): Widget\Base\Contents->___content() #7 /www/wwwroot/xiamp.net/var/Widget/Archive.php(1500): Typecho\Widget->__get() #8 /www/wwwroot/xiamp.net/var/Typecho/Router.php(99): Widget\Archive->feed() #9 /www/wwwroot/xiamp.net/index.php(23): Typecho\Router::dispatch() #10 {main}