From: "Jesús Gabriel y Galán" <jgabrielygalan@...>
Date: 2008-04-23T16:50:35+09:00
Subject: Re: Extract date from filenames using regex

On Wed, Apr 23, 2008 at 9:14 AM, Clement Ow
<clement.ow@asia.bnpparibas.com> wrote:
>  Thanks Daniel for your input. I tried using /\d+/ but it'll extract
>  files that have even 2 numbers to i decided to use
>  /(\d\d)(\d\d)(\d\d\d\d)/ instead. It enabled me to run the command on
>  certain files but not all files and the following error occured:
>
>  report_16042008.dat size: 77 KB
>  c:/ruby/lib/ruby/1.8/date.rb:1536:in `new_by_frags': invalid date
>  (ArgumentError
>  )
>         from c:/ruby/lib/ruby/1.8/date.rb:1583:in `parse'
>         from testing.conf.rb:166:in `delFiles'
>         from testing.conf.rb:163:in `glob'
>         from testing.conf.rb:163:in `delFiles'
>         from testing.conf.rb:162:in `each'
>         from testing.conf.rb:162:in `delFiles'
>         from testing.conf.rb:204
>
>  Is there anything wrong with mycode that prevents deleting all the files
>  that I want?

OK, now I see the problem. The file that is failing has a number like this:
16042008. The DateTime.parse method is trying to parse the date as:

1604-20-08 which is obviously an invalid date (month > 12).
There are two solutions to this problem:

1.- Change DateTime.parse to DateTime.strptime passing a format
that describes where in the string you have the two digits of the day, the month
and the four digits of the date. I haven't been able to gather a quick example,
cause I don't find a reference for the format string (any help here
appreciated).
The doc refers me to the date/format.rb for details and I don't see
anything clear
there.

2.- Change the regexp a little bit so you capture the day, the month
and the year
in separate groups and create the DateTime using the three values:

irb(main):011:0> regexp = Regexp.compile(/(\d{4})(\d{2})(\d{2})/)
=> /(\d{4})(\d{2})(\d{2})/
irb(main):012:0> m = regexp.match("20080103asdfasdf")
=> #<MatchData:0xb7c11a6c>
irb(main):014:0> d = DateTime.civil m[1].to_i, m[2].to_i, m[3].to_i
=> #<DateTime: 4908937/2,0,2299161>
irb(main):015:0> d.to_s
=> "2008-01-03T00:00:00+00:00"

I think you can apply the above changes to the script and it will work.
Let me know,

Jesus.