Re: [Cppcms-users] app().session().erase() doesn't work or not permitted?

[Artyom B. <art...@ya...>]

> 

> string msg;
> 
> if (app().session().is_set("msg")) {
>     msg = app().session().get("msg"); //works
>     app().session().erase("msg"); // doesn't work
> }
> 
> return msg; // always returns text because it never gets erased
> 
> Is modifying a session via app().session() not permitted or is it a bug?
> Erasing the key from controller works fine.
> 


You can't do changes in session **after** writing **any** output
(including just accessing to response().out() without actual I/O)

> Another question - why is session_interface::get() not const?
> 

Because it allows to use lazy evaluation, caching etc... You will not find many
const member functions in general withing CppCMS for this reason.

> Cheers,
> Petr
>

Artyom