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    <p>On searching more, I found an answer to at least part of my question:</p> <p>Based on: <a href="http://wikis.onestepback.org/index.cgi/Tech/Ruby/RubyBindings.rdoc/style/print" rel="noreferrer">http://wikis.onestepback.org/index.cgi/Tech/Ruby/RubyBindings.rdoc/style/print</a></p> <p>The rest is from experimentation after Jim Shubert's helpful pointers.</p> <ol> <li>This can be accomplished by <code>eval</code>-ing <code>local_variables</code>, <code>instance_variables</code> and <code>global_variables</code> inside the binding.</li> <li>You can do something as described below, given <code>var_name</code>, <code>new_val</code>, <code>my_binding</code> (syntax may be imperfect or improvable, feel free to suggest in comments. Also, I couldn't get the code formatting to work inside the list, suggestions for how to do that will also be implemented.)</li> <li>You can straightforwardly take (2) and loop the hash to do this.</li> <li>See the second code block below. The idea is to start with TOPLEVEL_BINDING, which I believe normally just includes the global variables.</li> </ol> <p>This does involve using string <code>eval</code>. However, no variable values are ever expanded into the strings involved, so it should be fairly safe if used as described, and should work to 'pass in' complex variable values.</p> <p>Also note that it's always possible to do <code>eval var_name, my_binding</code> to get a variable's value. Note that in all of these uses it's vital that the variable's <em>name</em> be safe to eval, so it should ideally not come from any kind of user input at all.</p> <p>Setting a variable inside a binding given <code>var_name</code>, <code>new_val</code>, <code>my_binding</code>:</p> <pre><code># the assignment to nil in the eval coerces the variable into existence at the outer scope setter = eval "#{var_name} = nil; lambda { |v| #{var_name} = v }", my_binding setter.call(new_val) </code></pre> <p>Building a "bespoke" binding:</p> <pre><code>my_binding = eval "lambda { binding }", TOPLEVEL_BINDING # build a nearly-empty binding # set_in_binding is based on the above snippet vars_to_include.each { |var_name, new_val| set_in_binding(var_name, new_val, my_binding) } </code></pre>
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    1. POIs 'eval' the only way to interact with binding objects in Ruby?
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    1. USWalter Mundt
    1. USWalter Mundt
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    1. POIs 'eval' the only way to interact with binding objects in Ruby?
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    1. COExcellent research!
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      1. USJim Schubert
    2. COAccepting this, but if anyone comes along who knows how to avoid the use of string eval for this stuff, please contribute your knowledge.
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      1. USWalter Mundt
 

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