in reply to checking dates in strings

An alternate approach -- one that makes pesky things like leap years easier to cope with -- is first filter for things that look like dates, then validate them with a separate routine. Something like the following: 
  s#((\d+)-(\d+)-(\d+))#isDate($2,$3,$4) ? "<date>$1</date>" : $1#e;

  sub isDate {
      my($d,$m,$y) = @_;
      # ... return 1 if these are a valid date, else 0
  }

[download]
Where isDate() is left as an exercise.

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Re: Re: checking dates in strings
by Anonymous Monk on Nov 11, 2002 at 00:49 UTC
    cool, that's a good idea, can you just give me a small hint as how to check if say $1 is in the set 10-19 ?
[reply]
      can you just give me a small hint as how to check if say $1 is in the set 10-19 ?

      Thanks to the outer set of parenthesis, $1 is the complete string matched. It gets substituted for itself if isDate($2,$3,$4) return 0. You can check numbers individually inside of isDate(), where they're available in $d, $m, and $y respectively.

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[d/l]
[select]
        i am just trying to do this small problem right now 
        
$brian = 17;
if($brian =~ /^1[0-9]$/){
            print "$brian is between 10 and 19";
}

        [download]
        i cannot figure out why this doesn't work. can someone please help?
[reply]
[d/l]

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