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copied!<p>I don't believe there's any way to do this in Ruby (if anyone comes up with one, please let me know, and I'll update or delete this answer to reflect it!) - if a local variable hasn't been defined yet, there's no way to dynamically define it with the binding. You could conceivably do something like <code>orange, lemon, grapefruit = nil</code> before calling eval, but you may run into other problems - for instance, if args[:orange] is the string "Orange", you'll end up evaluating <code>orange = Orange</code> with your current implementation.</p> <p>Here's something that could work, though, using the <a href="http://ruby-doc.org/stdlib/libdoc/ostruct/rdoc/classes/OpenStruct.html" rel="nofollow noreferrer">OpenStruct</a> class from the standard library (by "could work", I mean "it's up to your sense of style whether <code>a.orange</code> is any nicer than <code>args[:orange]</code>"):</p> <pre><code>require 'ostruct' def my_method_with_ostruct(args) a = OpenStruct.new(args) puts "my_method_with_ostruct variables: #{a.orange}, #{a.lemon}, #{a.grapefruit}" end </code></pre> <p>If you don't need easy access to any state or methods on the receiver of this method, you could use <a href="http://ruby-doc.org/core/classes/Object.html#M000334" rel="nofollow noreferrer">instance_eval</a>, as follows.</p> <pre><code>def my_method_with_instance_eval(args) OpenStruct.new(args).instance_eval do puts "my_method_with_instance_eval variables: #{orange}, #{lemon}, #{grapefruit}" end end </code></pre> <p>You could even do <a href="http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-core/19153" rel="nofollow noreferrer">something tricky with method_missing</a> (see <a href="http://www.dcmanges.com/blog/ruby-dsls-instance-eval-with-delegation" rel="nofollow noreferrer">here</a> for more) to allow access to the "primary" object, but the performance probably wouldn't be great.</p> <p>All in all, I think it's probably most straightforward/readable to go with the less DRY initial solution that bothered you.</p>

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