PHP7 is much closer to 5 than Python 3 was to 2. Aside of a few very clearly defined changes, PHP 7 happily runs php5 code. Python 3 made huge changes, especia

PHP7 is much closer to 5 than Python 3 was to 2. Aside of a few very clearly defined changes, PHP 7 happily runs php5 code. Python 3 made huge changes, especially to string handling and input/output which is what most applications do all the time. And perl 6 is practically a completely different language. I wouldn't count that. What is interesting about php7 is how much effort and how little complaining goes into porting the C extensions: that API has changed a lot and the documentation is still spread all over wikis and blog posts. And yet there is a php7 port of many third party extensions already But I guess the huge performance improvements are a strong motivator even there