title: Can a PHP object variable start with a number?
body: <p>I've was working on some old parts of a website and found myself in a situation where I have to run the following code </p>
  
  <pre><code>&lt;?=($stone-&gt;2_way)? 'checked' : ''?&gt;
  </code></pre>
  
  <p>Attempting to do this causes the page to crash while this </p>
  
  <pre><code>&lt;?=($stone-&gt;rectangular)? 'checked' : ''?&gt;
  </code></pre>
  
  <p>doesn't.  I'm wondering if it is because the variable starts with a number? I can var_dump the stone object and get </p>
  
  <pre><code>object(Cut_Stone)#54 (6) {
    ["errors"]=&gt;
    NULL
    ["attributes":"ActiveRecord\Model":private]=&gt;
    array(13) {
      ["stone_id"]=&gt;
      int(24)
      ["stone_name"]=&gt;
      string(11) "Test Stone "
      ["active"]=&gt;
      int(1)
      ["rectangular"]=&gt;
      int(1)
      ["2_way"]=&gt;
      int(1)
      ["3_piece_radius"]=&gt;
      int(1)
      ["3_piece_straight"]=&gt;
      int(1)
      ["wedge"]=&gt;
      int(1)
      ["partial_wash"]=&gt;
      int(1)
      ["pier_cap"]=&gt;
      int(1)
      ["pier_cap_w_flat"]=&gt;
      int(1)
      ["radiused_hearth"]=&gt;
      int(1)
      ["total_washed"]=&gt;
      int(1)
    }
    ["__dirty":"ActiveRecord\Model":private]=&gt;
    array(0) {
    }
    ["__readonly":"ActiveRecord\Model":private]=&gt;
    bool(false)
    ["__relationships":"ActiveRecord\Model":private]=&gt;
    array(0) {
    }
    ["__new_record":"ActiveRecord\Model":private]=&gt;
    bool(false)
  }
  </code></pre>
  
  <p>Also it is important to note that this object has been used in other places without fail, so I don't really get what is going on here.</p>