in reply to Match Optional Groups with 1 Required Group

print "$_: ", m[^\w+(?:\.\w+){0,2}$] ? 'matched' : 'failed'  
    for qw[ one one.two one.two.three one. one-two ];;
one:  matched
one.two:  matched
one.two.three:  matched
one.:  failed
one-two:  failed

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With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

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Re^2: Match Optional Groups with 1 Required Group
by rem45acp (Novice) on Feb 04, 2014 at 00:48 UTC
    This is great. I should have put in the post that there can be an unlimited number of titles, as long as there is one. I'm trying to modify it to allow that: 
    print "$_: ", m[^\w+(?:\.\w+)?$] ? "matched\n" : "failed\n"
    for qw[ one one.two one.two.three four.five.six.seven one. one-two
+ ];

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[reply]
[d/l]

      ? is zero or one. You need *, which is 0 or more.:

      print "$_: ", m[^\w+(?:\.\w+)*$] ? "matched\n" : "failed\n"
     for qw[ one one.two one.two.three four.five.six.seven one. one-tw
+o ];;
one:  matched
one.two:  matched
one.two.three:  matched
four.five.six.seven:  matched
one.:  failed
one-two:  failed

      [download]
      Each title needs at least one character as well.

      + means 1 or more, so that's covered by \w+

      With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
      Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
      "Science is about questioning the status quo. Questioning authority".
      In the absence of evidence, opinion is indistinguishable from prejudice.
[reply]
[d/l]
Re^2: Match Optional Groups with 1 Required Group
by rem45acp (Novice) on Feb 04, 2014 at 00:49 UTC
    Each title needs at least one character as well.
[reply]
      Ah sweet.
[reply]

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