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POclass_variable_set gives `NameError: unintialized class variable in Object` when variable accessed
 

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  1. POclass_variable_set gives `NameError: unintialized class variable in Object` when variable accessed
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    <p>I'm doing the following, and expecting <code>TestClass.my_var</code> to return<code>"my_var_here"</code>:</p> <pre><code>irb(main):001:0&gt; def create_a_class class_name, my_var irb(main):002:1&gt; klass = Object.const_set class_name, Class.new irb(main):003:1&gt; klass.class_variable_set :@@my_var, my_var irb(main):004:1&gt; klass.instance_eval do irb(main):005:2* def my_var irb(main):006:3&gt; @@my_var irb(main):007:3&gt; end irb(main):008:2&gt; end irb(main):009:1&gt; klass irb(main):010:1&gt; end =&gt; nil irb(main):011:0&gt; create_a_class "TestClass", "my_var_here" =&gt; TestClass </code></pre> <p>Instead, I get this:</p> <pre><code>irb(main):012:0&gt; TestClass.my_var (irb):6: warning: class variable access from toplevel NameError: uninitialized class variable @@my_var in Object from (irb):6:in `my_var' from (irb):12 from C:/Ruby193/bin/irb:12:in `&lt;main&gt;' </code></pre> <p>What am I doing wrong? Any input would be appreciated.</p> <p>EDIT: I've tried doing it like this and it seems to work, but it doesn't really feel like The Ruby Way™ of doing it (also I'd rather not have those pesky warnings)</p> <pre><code>irb(main):001:0&gt; def create_a_class class_name, _my_var irb(main):002:1&gt; klass = Object.const_set class_name, Class.new irb(main):003:1&gt; klass.instance_eval do irb(main):004:2* @@my_var = _my_var irb(main):005:2&gt; def my_var irb(main):006:3&gt; @@my_var irb(main):007:3&gt; end irb(main):008:2&gt; end irb(main):009:1&gt; klass irb(main):010:1&gt; end =&gt; nil irb(main):011:0&gt; create_a_class "TestClass", "my_var_here" (irb):4: warning: class variable access from toplevel =&gt; TestClass irb(main):012:0&gt; TestClass.my_var (irb):6: warning: class variable access from toplevel =&gt; "my_var_here" </code></pre>
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