$line = qq~I'm looking for the end of a sentence, where possible.  However, in some cases, I'll need to go with a non-conventional "end" to it, such as:

"Here's a quote by a famous person which is supposed to exceed forty words and is therefore required to be set apart as a separate, indented paragraph per APA style." (Famous, 1999)

Note that the regex needs to look for the full end of the sentence, if it exists: it cannot simply stop at the colon unless there is no further part to the sentence provided in that paragraph.~;


$line =~ s/^
   (.*?)
   (
      (?:[.?!"])      #FIRST PRIORITY
       |
      (?:[:;-])      #SECOND PRIORITY
      |
      (?:\n|\r|\z|$)   #LAST PRIORITY
   )
   /<span class="s">$1$2</span>/gmx;
##</code><code>##

$line =~ s~^
(
   Point\s(\d+)\.(\d+)\.(d+)
   (.*?)
)   
   (?=
      (?:Point\s
         (?:\d+)\.(?:\d+)\.(?!\4)
      )   #1 Priority
      |
      (?:\z|$)  #2 Priority
   )
  ~$processthis->()~egmx;