Re: Pattern Matching in Arrays

One way, which would be slow for directories with lots of files would be something like this. Sort the array of filenames, then use the pars before the _ as hash keys, the elements just overwrite the previous values.

#!/usr/bin/perl
use strict;
use warnings;

my @data = qw/12345_-v1.pdf 12345_Av1.pdf 123456_-v1.pdf 123456_Av1.pd
+f 123456_Bv1.pdf/;
my %hash;

for my $f (sort @data) {
  my ($key,$version) = split /_/,$f;
  $hash{$key} = $version;
}

for my $key (keys %hash) {
  print $key . '_' . $hash{$key} . "\n";
}
[download]

--
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Comment on Re: Pattern Matching in Arrays Download Code

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Re^2: Pattern Matching in Arrays by aj.kohler (Initiate) on May 12, 2009 at 13:49 UTC
Thank you for you help I came across an issue after reviewing the data The core number is the 12345 portion, as assumed. However, there are some filenames that have multiple underscore characters in the name, before it gets to the version value. Examples: g05495_1_-v1.pdf 21586_rework_bore_tool_-v2.pdf 4148-t-14119_-v1.pdf zprt0019548_wiper_die-nc_-1.pdf zprt0016809_fg_tooling_A2.pdf The -v1, -v2, -v1, -1, A2 are the version keys, and everything before that is the core document number. Any thoughts on how to address these?	[reply]
Re^3: Pattern Matching in Arrays by przemo (Scribe) on May 12, 2009 at 17:59 UTC
In such case, you have to know where the end is to determine, where the last `_' is... I'll assume that the filename ends with .pdf: `if ($filename =~ /^(.)_(.)\.pdf$/) { # do something with $1 and $2 here }` [download] Because of the Perl "longest-first" matching, the underscore will match the last underscore in the filename.	[reply] [d/l]
Re^4: Pattern Matching in Arrays by aj.kohler (Initiate) on May 12, 2009 at 20:09 UTC
I liked the split method recommended above. Can you use the OR in the split command to pattern match at the time of the split? There is a new wrinkle in the mix as well. There are filenames without "_": 12345.pdf All comments are welcomed!	[reply]
Re^5: Pattern Matching in Arrays by przemo (Scribe) on May 12, 2009 at 22:44 UTC
Re^6: Pattern Matching in Arrays by aj.kohler (Initiate) on May 13, 2009 at 18:28 UTC
Re^5: Pattern Matching in Arrays by ciderpunx (Vicar) on May 13, 2009 at 17:01 UTC


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