Reset the whole state

[Remi Gillig]

Hello,

I just seached about this problem and found two 2 years old threads :
http://groups.google.com/group/comp.lang.ruby/browse_thread/thread/875a099efd08f70d
http://groups.google.com/group/comp.lang.ruby/browse_thread/thread/3e6fa1a935e50697

Each of these talk about how to reset the whole Ruby state, like
starting from a clean interpreter but without rerunning it. More or
less like emptying everything and putting back the predefined
constants, modules and classes.

The first thread has a solution which is using remove_const to not be
able to create classes anymore but this actually does not work
properly because you can still do this :
# class Hello end
# $hello = Hello
# Object.instance_eval("remove_const :Hello")
# h = $hello.new

I'm quite surprised that there was nothing about this in over 2 years
of development. Maybe there are some explanation inside the Ruby
Hacking Guide but most of it is in Japanese.

Anybody has any idea on how to implement this? Thanks.

Remi Gillig.

 

[Robert Klemme]

Hello,

I just seached about this problem and found two 2 years old threads :
http://groups.google.com/group/comp.lang.ruby/browse_thread/thread/875a099efd08f70d
http://groups.google.com/group/comp.lang.ruby/browse_thread/thread/3e6fa1a935e50697

Each of these talk about how to reset the whole Ruby state, like
starting from a clean interpreter but without rerunning it. More or
less like emptying everything and putting back the predefined
constants, modules and classes.

The first thread has a solution which is using remove_const to not be
able to create classes anymore but this actually does not work
properly because you can still do this :
# class Hello end
# $hello = Hello
# Object.instance_eval("remove_const :Hello")
# h = $hello.new

I'm quite surprised that there was nothing about this in over 2 years
of development. Maybe there are some explanation inside the Ruby
Hacking Guide but most of it is in Japanese.

Anybody has any idea on how to implement this? Thanks.

I am wondering what you need that for. I guess removal is pretty
complex and thus time consuming because even a freshly started Ruby
interpreter does contain some classes and method definitions. And
creating a process isn't that expensive.

Having said that, maybe you can look at how Ruby can be embedded in C
programs. Then you could create a new initial context if something like
that exists.

Cheers

robert

 

[Remi Gillig]

I am wondering what you need that for. I guess removal is pretty
complex and thus time consuming because even a freshly started Ruby
interpreter does contain some classes and method definitions. And
creating a process isn't that expensive.

Having said that, maybe you can look at how Ruby can be embedded in C
programs. Then you could create a new initial context if something like
that exists.

Cheers

robert

It's actually embedding that I'm using right now. I am using Ruby as a
script language for a code editor to perform operations on text etc.
There is a script which is loaded when the program loads which
contains
some classes defined by the user for example. I would like to be able
to
reload this script without having warnings about constants, having
classes mixed together if the user changed the name of a function
between the loadings or still having the same global variables.

Remi Gillig.

 

[David Marchaland]

Hi Remi,

I have the same approach that you describe in your post regarding
embedded Ruby interpreter. I did some trial based on dl library in C to
dynamically open and close Ruby interpreter but I had some issue due to
dlclose() behavior when a so library is loaded into Ruby.

Do you find any solution to restart your Ruby interpreter?

Thanks,
David