It's the comma operator. In this case, the comma expression is evaluated in a scalar context (dictated by the or), but still each argument is evaluated; that's the intent here (i.e. the ultimate return value of the expression is not used). A more straightforward alternative for that line would be 

if ( !DO_SOMETHING ) {
  warn("some warning");
  next;
}

[download]
or 
unless ( DO_SOMETHING ) {
  warn("some warning");
  next;
}

[download]

the lowliest monk

In reply to Re: using 'or' followed by ',' by tlm
in thread using 'or' followed by ',' by mathew_

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