# The scope of local variables -- where are they? **URL:** \ **Category:** Ruby\ **Created:** [September 8, 2007, 3:17pm UTC](https://www.ruby-forum.com/t/the-scope-of-local-variables-where-are-they/114146 "2007-09-08T15:17:04Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![unnali](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/97f17d/32.png) [@unnali](https://www.ruby-forum.com/u/unnali)\ **Post date:** [September 8, 2007, 3:17pm UTC](https://www.ruby-forum.com/t/the-scope-of-local-variables-where-are-they/114146/1 "2007-09-08T15:17:04Z")
I’m wondering – where /is/ the scope of local variables? Is there any programmatic way to manipulate a local variable [by this, I rather awkwardly mean – for example, is there a hash on some object of local variables? Or something similar?] They seem special to me. Cheers, Arlen ---
**Author:** ![unnali](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/97f17d/32.png) [@unnali](https://www.ruby-forum.com/u/unnali)\ **Post date:** [September 8, 2007, 3:34pm UTC](https://www.ruby-forum.com/t/the-scope-of-local-variables-where-are-they/114146/2 "2007-09-08T15:34:05Z")
I wanna know how to do it so. Some method that receive a simple, just like const\_(get|set). ---
**Author:** ![unnali](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/97f17d/32.png) [@unnali](https://www.ruby-forum.com/u/unnali)\ **Post date:** [September 8, 2007, 3:58pm UTC](https://www.ruby-forum.com/t/the-scope-of-local-variables-where-are-they/114146/3 "2007-09-08T15:58:07Z")
I know I can user defined? to test if they are defined, but is there any way to get them throught metaprogramming? ---
**Author:** ![unnali](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/97f17d/32.png) [@unnali](https://www.ruby-forum.com/u/unnali)\ **Post date:** [September 9, 2007, 4:44am UTC](https://www.ruby-forum.com/t/the-scope-of-local-variables-where-are-they/114146/4 "2007-09-09T04:44:21Z")
On 9/8/07, Bernardo Monteiro R. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > I know I can user defined? to test if they are defined, but is there any way > to get them throught metaprogramming? No (except for eval). What do you want to acheive? Whatever it is, there is probably another way, barring wanting to mess with local variables for the sake of messing with local variables. ---
**Author:** ![unnali](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/97f17d/32.png) [@unnali](https://www.ruby-forum.com/u/unnali)\ **Post date:** [September 8, 2007, 3:51pm UTC](https://www.ruby-forum.com/t/the-scope-of-local-variables-where-are-they/114146/5 "2007-09-08T15:51:06Z")
On 08.09.2007 15:15, Arlen Christian Mart C. wrote: > I’m wondering – where /is/ the scope of local variables? Is there any > programmatic way to manipulate a local variable [by this, I rather > awkwardly mean – for example, is there a hash on some object of local > variables? Or something similar?] They seem special to me. There is a fairly easy way to manipulate them: foo = 10 🙂 If your set of variables you need to manipulate is not fixed you better use a Hash directly. There are some ways to manipulate “unknown” local variables, but they typically involve using “eval”. You’ll find plenty of discussions of this topic in the archives. Kind regards robert ---
**Author:** ![unnali](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/97f17d/32.png) [@unnali](https://www.ruby-forum.com/u/unnali)\ **Post date:** [September 9, 2007, 5:52am UTC](https://www.ruby-forum.com/t/the-scope-of-local-variables-where-are-they/114146/6 "2007-09-09T05:52:24Z")
On 09/09/2007, Logan C. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > > One use I could see for reflection on local variables is debugger support. You’ve run to a breakpoint; what is the full program state? ---
**Author:** ![unnali](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/97f17d/32.png) [@unnali](https://www.ruby-forum.com/u/unnali)\ **Post date:** [September 9, 2007, 1:17pm UTC](https://www.ruby-forum.com/t/the-scope-of-local-variables-where-are-they/114146/7 "2007-09-09T13:17:54Z")
On 9/8/07, Michael R. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > One use I could see for reflection on local variables is debugger > support. You’ve run to a breakpoint; what is the full program state? That’s a pretty good example 🙂 (we do have local\_variables, but’s that is jsut an array of strings)