in reply to Re: file::find and ordered output
in thread file::find and ordered output

I had a look at the manpage (it wasn't the first ;-) but couldn't quite understand how this (preprocess) would help me in my problem.

quoting the man page of "file::find => preprocess"

The value should be a code reference. This code reference is used to preprocess the current directory. The name of currently processed directory is in $File::Find::dir. Your preprocessing function is called after readdir() but before the loop that calls the wanted() function. It is called with a list of strings (actually file/directory names) and is expected to return a list of strings. The code can be used to sort the file/directory names alphabetically, numerically, or to filter out directory entries based on their name alone. When follow or follow_fast are in effect, preprocess is a no-op.

"This code reference is used to preprocess the current directory."

How can it affect the order of the directory processing?

pondering

Bjoern

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Re: Re: Re: file::find and ordered output
by broquaint (Abbot) on May 13, 2002 at 10:13 UTC
    How can it affect the order of the directory processing?
    Its effect is that it changes what is passed to the wanted() coderef e.g 
    find({
    preprocess => sub { return sort { $b cmp $a } @_ },
    wanted     => \&process_array,
}, @ARGV);

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    This will sort the directory listing that process_array() gets in reverse alphabetic order. So basically the preprocess option allows you to change what the wanted() function receives from changing it's order to removing unwanted directory entries.
    HTH

    _________
    broquaint

    update: changed <=> to cmp in the sort() (thanks ariels)

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      Thank you for the prompt input.

      The modification from "<=>" to "cmp" does it. It works fine now.

      Thanks again.

      Bjoern
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      With your help I seem to get near the solution, but still it's weird...

      with $a <=> $b I get 
      Anastacia
Springsteen
Laith al Deen

      [download]

      with $b <=> $a I get 
      Laith al Deen
Springsteen
Anastacia

      [download]

      there seems to be a kind of sense in the output, but it's still not sorted correct....(or the alphabet in my brain is mixed up)

      I will work on it this evening an let you know about the solution (hope I find one), thanks for the input!

      still pondering

      Bjoern
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