I don't care too much about specific skills in this sort of a situation. What matters to me is that the interviewee actually knows perl, and that they have good problem solving skills.

So I find a few basic questions can tell me that.

• Show them a simple class I mock up and ask them to write a derived class
• Ask them to write a simple few lines to load a file and sort the contents with a basic numeric sort.
• Give them a semi-complex data structure and ask them to sort it in a certain way

I'm looking for error checking, the thought process on the last one that might lead them in the direction of a Schwatzian Transform, and some essential problem-solving skills. In fact, to me, "I'd need to read the perldoc on sorting to figure it out", or, "I'd have to check some documentation to remember if I need to 'use Exporter'", are perfectly good responses.