> There'd be an interaction between is topic_preserving, default parameter > values, and explicit parameter values which should be clarified. Now I > understand why someone suggested using //= $_ instead of is > topic_preserving, somewhere along the line. Clearly if the user > supplies the parameter, is topic_preserving would limit itself to making > that parameter available as $_ within the sub. If the user supplied > both //= 3 and is topic_preserving, that would either be a bug or a > feature. I guess as a feature, it would use $_, but if $_ were undef, > then it would use 3 ???
Personally, I like //= $_. It's clear, such that a reader would immediately know what it's doing. topic_preserving, despite being more verbose, is not so clear. Plus, if someone didn't know about that feature, that's probably the first thing they would do (provided they knew about defaults) to accomplish that task. Luke
