You've mistaken the x modifier: Memorize "eXpressive", meaning that you can use whitespace and even comments within a regex without impact on the pattern. 
/ f      # this matches "foo"
  o      # and nothing else
  o /x

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In reply to Re: Improving my regex skills and a few questions. by Django
in thread Improving my regex skills and a few questions. by BrowserUk

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