In the meeting in Paris on November 2005 it was decided that PHP should have return type declarations and some suggestions were made for syntax. Suggestion 5 is nearly compatible with this RFC; however, it requires the addition of a new token T_RETURNS. This RFC opted for a syntax that does not require additional tokens so returns was replaced by a colon.https://wiki.php.net/rfc/return_types
не вижу, чтобы там было указано, что для объявления типа ВЫ ДОЛЖНЫ ИСПОЛЬЗОВАТЬ ДВОЕТОЧИЕэто видно из примеров, не знаю или это где–то отдельно описано кроме rfc.
When I say HiDPI, I mean the pixel-doubling a Retina display does to get this super awesome smooth and sharp picture.
Enabling HiDPI will not lead to optimal results, since the monitor should have a 4k or 5k resolution, but it will improve the picture a litte.