Re: Trouble with regular expression

Regexp::Common::time from the Regexp::Common family of modules, will assist you here.

If you are absolutely, positively certain of the format of your input, then you can also try (assuming your input is in $_):

($year, $month, $day, $hour, $min, $sec) = m|\d{4})/(\d{2})/(\d{2}) (\
+d{2}):(\d{2}):(\d{2})|;
[download]

CountZero

A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James

Comment on Re: Trouble with regular expression Select or Download Code

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Re^2: Trouble with regular expression by northwestdev (Acolyte) on Jun 08, 2009 at 07:19 UTC
Thanks. I think you're missing a ( after m\| I played around with it a little bit. d+ instead of d{4}, d{2} also works.	[reply]
Re^3: Trouble with regular expression by CountZero (Bishop) on Jun 08, 2009 at 09:44 UTC
Indeed a missing "(": I blame it on my less than perfect "copy-and-paste"-fu! `\d+` works, but as a general rule in a regex one should try to be as restrictive as possible, in order for the regex to pass only what is exactly right. For instance, `\d+` allows something like "123456789" for any of the elements and that is surely wrong. By the same token, `\d{2}` isn't perfect either as it allows "99" for the number of months, days, hours, minutes or seconds. Regexp::Common::time has the following regex for the number of months: `/(?:(?=[01])(?:0[1-9]\|1[012]))/` [download] That regex does not allow "wrong" numbers for the month and there are similar regexen for days, hours, ... In the end it all comes down to how much you trust your input to do no funny things. CountZero A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James	[reply] [d/l] [select]
Re^3: Trouble with regular expression by ww (Archbishop) on Jun 08, 2009 at 10:58 UTC
Your `(\d+)` works ... if you're willing to accept bad data -- for example, data with a one-, three- or (> four)-digit year. You'd do well to read perlretut and friends re quantifiers. Insisting on a regex is not always the best idea. That's implicit in CountZero's "absolutely, positively certain...." <Update> and in his excellent followup, written as I piddled about with this note.</update> And, even more to the point, insisting on a regex suggests that you failed to grok the replies to your earlier String (date) to time (integer).	[reply] [d/l]