There's a datastructures extension being worked on for php7 that has extensive tests and a polyfill to be used when the extension is not available. This might be interesting for us to use as a base for our collection implementations when going to php7 compatibility:
There's a datastructures extension being worked on for php7 that has extensive tests and a polyfill to be used when the extension is not available. This might be interesting for us to use as a base for our collection implementations when going to php7 compatibility: