Re^3: How can i debug compound map/grep statements just using print?

in reply to Re^2: How can i debug compound map/grep statements just using print?
in thread How can i debug compound map/grep statements just using print?

You have the following:

=item B<-a, --amount>

Search for files older than <amount> days, mandatory.
[download]

In two days, there are 2 * 24 * 60 * 60 or 172800 seconds, thus it seemed that the following was needed:

$amount = $amount * 24 * 60 * 60;
[download]

since one day equals 24 * 60 * 60 or 86400 seconds. Additionally, the following worked when I ran it using the above formula for $amount:

$result =
  grep { /.+\.$suffix$/ and $time - ( $_->stat )[9] >= $amount }
  io($dir)->all;
[download]

An equivalent search can be done using File::Find::Rule:

$result = File::Find::Rule->file()
                          ->maxdepth(1)
                          ->name(qr/.+\.$suffix$/i)
                          ->mtime(">= $amount")
                          ->in($dir);
[download]

And the following, too, but grepping on days old instead of using mtime:

$result = grep { -M >= $amount / 86400 } # Convert back to days
          File::Find::Rule->file()
                          ->maxdepth(1)
                          ->name(qr/.+\.$suffix$/i)
                          ->in($dir);
[download]

All three methods produced the same result, even when an equivalent constant was used for the days in the last grep.

After adjusting the $amount formula, your original code produced the same result, too:

    $result =
      grep { $_ == 1 }
      map  { $time - $_ >= $amount }
      map  { ( $_->stat )[9] }  # e.g i'm interested in this...
      grep { $_->name =~ /.+\.$suffix$/ } # ...and this
      io($dir)->all;
[download]

Thus, all four code snippets produced identical results.

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Re^4: How can i debug compound map/grep statements just using print? by karlgoethebier (Abbot) on Dec 02, 2012 at 00:03 UTC
"An equivalent search can be done using File::Find::Rule" This is simply true, but what i wanted to do was this: Not using File::Find Not using File::Find::Rule" Not using `qx(find...[options])` Bothering myself with map/grep Thank you very much for your advice and the insights you gave to me. Regards, Karl ŤThe Crux of the Biscuit is the Apostropheť	[reply] [d/l]
Re^5: How can i debug compound map/grep statements just using print? by Kenosis (Priest) on Dec 02, 2012 at 01:55 UTC
I really should have said that I wasn't suggesting a different or better way by using File::Find::Rule. Only used it to verify your results (like inter-rater reliability). Yours was a good map/grep piece. Nice update, by the way...	[reply]
Re^4: How can i debug compound map/grep statements just using print? by karlgoethebier (Abbot) on Dec 01, 2012 at 23:22 UTC
Sorry about that awkward typo: should have been hours... ŤThe Crux of the Biscuit is the Apostropheť	[reply]
Re^5: How can i debug compound map/grep statements just using print? by Kenosis (Priest) on Dec 01, 2012 at 23:59 UTC
Ah, yes--that makes sense! Used the hours calculation for all four snippets: `$amount = $amount * 60 * 60;` [download] and got identical results, until 79 hours was used (a result difference of 2), but I suspect the division in the `grep { -M >= $amount / 86400 }` yields a different precision. Interestingly, `IO::All` didn't see the file "song自然之歌," but `File::Find::Rule` did (and should have).	[reply] [d/l] [select]
Re^6: How can i debug compound map/grep statements just using print? by karlgoethebier (Abbot) on Dec 02, 2012 at 00:20 UTC
I'm lucky not having a file named இளவரசன்.mp3 ;-) ŤThe Crux of the Biscuit is the Apostropheť	[reply]
Re^7: How can i debug compound map/grep statements just using print? by Kenosis (Priest) on Dec 02, 2012 at 01:56 UTC

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