Since the discussion is becoming one of style preferenece, I'll add mine. Dispatch tables are often a suprise to someone reading through code. It's common for there to be only one in a module, if that, so it's good to call the reader's attention to what's going on. While I might use

   $op_map{$op_choice}->(@args);
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for a one-off, or where I was using it a lot, for most code I'd do something along the lines of naikonta's later suggestion, only with some correspondence between the names, as in

   my $op = $op_map{$op_choice};
   $op->(@args);
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This separates the lookup from the invocation, so the invocation is easier to see. It also makes adding a default function easier, as naikonta already showed.