Problem with taking inout, const references

[Uranuz]

> Your code compiles with the development branch of dmd. What 
> version are you using?
>
Now I'm using 2.064. May be this bug is already fixed. In 2.065 I 
experience problem that std.json library module is not compatible 
with code written for previous versions. This is why I returned 
to 2.064. As far as I understand these breaking changes were a 
mistake. Now I don't know how to deal with it. I'm not sure that 
using old Phobos verion with new compiler could be good solution. 
If were a mistake It doesn't sound reasonable to change existing 
code to compile with this version.