Final variables

Hello internals, Java supports the "final" keyword before a variable to determines that this variables never change it reference. If I declare a variable as "final", I can only initialize that once, then I could not change it after (but I can manipulate the instance, without issues). There some special reason to PHP doesn't supports things like that? final $number = 123; $number = 456; // Error: you change change final variables. final $object = new stdClass; $object->allowed = true; // No error. This feature make sense because it tells to dev that the variable value could not be updated directly (new reference). Which make easy to identify when a variable is modifiable or not. It is valid for a RFC? - It can uses the "final" keyword; - It doesn't a BC; I too think that a final variable can be useful to make some internal improvements on language (but it could be a BC for PHP internals). I mean, as the variable could not be modified, then it don't need be a "flexible" type internally (I guess that it is a zval, right?). Reference: https://github.com/kalessil/phpinspectionsea/issues/363 -- David Rodrigues