From: Jean-Hugues ROBERT <jean_hugues_robert@...>
Date: 2004-04-21T22:24:39+09:00
Subject: Re: binding - how to get current script?

At 21:09 21/04/2004 +0900, you wrote:
>On Wed, 21 Apr 2004 12:18:18 +0200, Szymon Drejewicz wrote:
>
> >
> >> A local variable created in eval is only visible in eval.
> >
> > :'-(
> >
> > so there is no way to do something like:
> >
> >         eval("name = 'Alice'", MAIN_BINDING)
> >         puts name
> >
>
>There is :-)
>You can use Kernel#binding to get the current binding,
>and pass it to eval:
>
>irb(main):001:0> eval("name = 'Alice'", binding())
>=> "Alice"
>irb(main):002:0> name
>=> "Alice"

However this bombs: eval("name = 'Alice'", binding); puts name
This is probably because the reference to name is compiled *before*
eval() is called. Basically: the local variable is created but
the compiled code does not bind to it.

Try this:
def test()
   eval( "a = 'titi'", binding)
   puts "Compiled: #{a}"
rescue
   eval( 'puts "Dynamic: #{a}"')
end
test()

Jean-Hugues



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