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copied!<p><strong>EDIT: The person who posted the original obfuscated example gave <a href="https://stackoverflow.com/questions/715951/if-this-code-is-not-a-joke-how-on-earth-does-it-work/716110#716110">the actual source code</a> in his answer. He also posted a <a href="https://stackoverflow.com/questions/715951/if-this-code-is-not-a-joke-how-on-earth-does-it-work/716139#716139">corrected version of the obfuscated code</a>, because as I noted, some of it didn't make sense even when you removed the funky syntax.</strong></p> <p>That is some nicely obfuscated code. As with most obfuscated code, it's mostly a lot of ternary operators and a stubborn refusal to put in whitespace where a normal person would. Here is basically the same thing written more normally: </p> <pre><code>class Tree def initialize(*d) @d, = d # the comma is for multiple return values, # but since there's nothing after it, # all but the first are discarded. end def to_s @l || @r ? ",>" : @d end def total total = @d.is_a?(Numeric) ? @d : 0 total += @l.total if @l total += @r.total if @r end def insert(arg) if @d if @l @l.insert(arg) else @l = Tree.new(arg) end else @d = arg end end end </code></pre> <p>The insert method is not syntactically valid (it's missing a method name at one part), but that's essentially what it does as far as I can tell. The obfuscation in that method is pretty thick:</p> <ol> <li><p>Instead of just doing <code>@l = whatever</code>, it uses <code>instance_variable_get()</code> and <code>instance_variable_set()</code>. Even worse, it aliases <code>instance_variable_get()</code> to just be <code>g()</code>.</p></li> <li><p>It wraps most of the functionality in a lambda function, to which it passes the name of the <code>@l</code>. Then it calls this function with the lesser-known syntax of <code>func[arg1, arg2]</code>, which is equivalent to <code>func.call(arg1, arg2)</code>.</p></li> </ol>

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