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How does one go about saying goodbye to all constants, objects, and the like defined in an irb session to return to a clean slate? By "in", I mean without manipulating subsessions.

fny
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2 Answers2

39

Type 

exec($0)

in your irb console session.

Andrew Marshall
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sunnyrjuneja
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    +1 LOL, awesome answer. And save a character and your shift key with `exec $0` – DigitalRoss Apr 22 '12 at 21:27
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    `exec __FILE__` would be better since it reload any scripts pulled in with IRB too: give `exec $0` in `rails console`, and you'll see what I mean. However, these commands don't maintain any options that were passed when executing `irb` (e.g. `irb --prompt simple`), and they'll both fail in a subsession. – fny Apr 22 '12 at 21:30
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    Pretty clever. Of course I'm not sure if this is faster than CTRL+D, ↑, enter. – Andrew Marshall Apr 22 '12 at 22:12
  • Perhaps this might be of some help to you? http://stackoverflow.com/questions/4749476/how-can-i-pass-arguments-to-irb-if-i-dont-specify-programfile Making a custom irb might be the only way to do it. – sunnyrjuneja Apr 22 '12 at 22:49
  • Customization did work; a custom IRB altogether would have been overkill. I ended up adding a function to `irbrc` that creates/destroys isolated namespaces wherein I can play. – fny Apr 23 '12 at 22:54
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i am using fedora 16, exec $0 do not work for me. but i found the the way below:

CTRL+L or system("clear") or system("reset")

lzj509649444
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  • `system("command")` actually executes the `command` in a subshell. The man pages tell us that `clear` will simply "clear the terminal screen". While `reset` comes with a few more bells and whistles, it still yields only a superficial change. Anything instantiated in the IRB session still lives on in memory. Sunny J's suggestion cleverly executes the command used to jump into IRB in the first place. I'm a bit puzzled, however, why you had trouble. What output do you see on `puts $0`? – fny Jun 03 '12 at 02:56