> > IIRC, they switched from object semantics to value semantics (like PHP > arrays). Can someone more knowledgeable confirm? >
Yes, sorry – Hack introduced the vec type (with value semantics) in 2016 after they'd experimented first with Vector (object semantics). Use of Vector is now discouraged. Details here: https://github.com/facebook/hhvm/issues/6451 FB/Hack appears to be in the multi-year process of moving all PHP arrays to one of [vec/dict/keyset]. That's likely not an option for PHP itself, but having the _option_ of a vec equivalent (in this proposal "list") would make sense, I think.
