<?php
        // The path into the array
        $GET_VARIABLE = "a.b.c";
        // Some example data
        $GLOBALS["a"]= array("b"=>array("c"=>"foo"));
 
        // Construct an accessor into the array
        $variablePath = explode( ".", $GET_VARIABLE );
        $accessor = implode( "' ][ '", $variablePath );
        $variable = "\$GLOBALS[ '". $accessor . "' ]";
 
        // Print the value for debugging purposes (this works fine)
        echo $GLOBALS["a"]["b"]["c"] . "\n";
        // Try to evaluate the accessor (this will fail)
        echo $$variable;
    ?>

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