For the most part the biggest hurdles about getting them into Perl are going to be the same as they are for anyone. Here are the PHP centeric points that spring to mind:

• Use strict or die.
  PHP coders can get into a lot of bad habits. As always, this will save everyone a lot of pain.
• CPAN is your friend.
  The power and flexibility of the CPAN will come as an epiphany to PHP programmers. PEAR is lightyears behind it.
• The difference between == and eq.
  This is always a big hurdle.
• sub vs. function
  

  function foo($bar = "Paco") { }
  [download]

  vs.

  sub foo { my $bar = shift || "Paco"; }
  [download]

• Object-Oriented Programming
  Perl's quirky yet powerful OO syntax will be hard for people used to PHP's much cleaner and weaker support.
• Know your data structures
  PHP variables are a very forgiving one size fits all that make moving over to Perl's stricter data structures a headache.

()-()
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