From: Peter Szinek <peter@...>
Date: 2006-11-12T02:42:26+09:00
Subject: eval question

Hi,

I am setting up a few variables based on user input with the following
code snippet:

==================================
vars = %w{a b c}

vars.each do |var|
  print "#{var} = "
  val = gets
  eval("$#{var}=#{val.chomp}")
end

#use a, b, c here for something
==================================

What I don't like about this code is the use of global variables.
However, I have to use them - or otherwise a,b,c will be already out of
scope at the place I need them.

Another possibility would be to use constants, i.e.

vars = %w{A B C}

which would work well - however, since I am repeating the process more
times, from the second iteration on I am getting warnings that A, B, C
etc were already initialized, which is not nice.

I guess yet another possibility would be to wrap a class around this
stuff and use instance_eval or something like that - but a class that
serves solely this purpose looks to heavy to me...

Any other ideas?

TIA,
Peter

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