Re: Changing variable names in a loop

If you want a parser that you don't have to change when you change your set of input criteria, you can do something like the following:

use strict;
use warnings;
use Data::Dumper;


my %config = map { /^((?:inc|exc)_\w+)=(.*)$/ } <DATA>;
print Dumper(\%config);



__DATA__
inc_albums= a list of albums to include
inc_genres= a list of genres to include
inc_artists= a list of artists to include
inc_songs= a list of songs to include
inc_year= a list of years to include
exc_albums= a list of albums to exclude
exc_genres= a list of genres to exclude
exc_artists= a list of artists to exclude
exc_songs= a list of songs to exclude
exc_year= a list of years to exclude
[download]

Which gives:

$VAR1 = {
          'inc_genres' => ' a list of genres to include',
          'inc_year' => ' a list of years to include',
          'exc_albums' => ' a list of albums to exclude',
          'inc_albums' => ' a list of albums to include',
          'exc_year' => ' a list of years to exclude',
          'exc_songs' => ' a list of songs to exclude',
          'inc_artists' => ' a list of artists to include',
          'inc_songs' => ' a list of songs to include',
          'exc_artists' => ' a list of artists to exclude',
          'exc_genres' => ' a list of genres to exclude'
        };
[download]

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Re^2: Changing variable names in a loop by Mad_Mac (Beadle) on Oct 16, 2010 at 09:45 UTC
NICE! That's even simpler than what I was expecting. :-D Thanks for the help. So, the values of the hash are a list separated by semicolons (just because I picked semicolons for the delimiter in my input text file). I need to put the list of values into an array, so I can use them to build my SQL statements. Sort of like this: # Maybe I can do this as part of the original parsing? # Or maybe I can loop over the %config hash and convert # the scalar values to an array, and put a reference # to that array back into the hash? @inc_albums=split(/; /, $inc_albums) unless $inc_albums=~/^\s$/; @inc_genres=split(/; /, $inc_genres) unless $inc_genres=~/^\s$/; @inc_artists=split(/; /, $inc_artists) unless $inc_artists=~/^\s$/; @inc_songs=split(/; /, $inc_songs) unless $inc_songs=~/^\s$/; @exc_albums=split(/; /, $exc_albums) unless $exc_albums=~/^\s$/; @exc_genres=split(/; /, $exc_genres) unless $exc_genres=~/^\s$/; @exc_artists=split(/; /, $exc_artists) unless $exc_artists=~/^\s$/; @exc_songs=split(/; /, $exc_songs) unless $exc_songs=~/^\s$/; my $i_albumcriteria=q{(Songs.Album LIKE '%'\|\|}.join(q{\|\|'%' OR Songs.A +lbum LIKE '%'\|\|},map {"?"} @inc_albums).q{\|\|'%')} unless (scalar(@inc +_albums)==0) ; my $i_artistcriteria=q{(Songs.Artist LIKE '%'\|\|}.join(q{\|\|'%' OR Songs +.Artist LIKE '%'\|\|},map {"?"} @inc_artists).q{\|\|'%')} unless (scalar( +@inc_artists)==0); my $i_songcriteria=q{(Songs.SongTitle LIKE '%'\|\|}.join(q{\|\|'%' OR Song +s.SongTitle LIKE '%'\|\|},map {"?"} @inc_songs).q{\|\|'%')} unless (scala +r(@inc_songs)==0); my $i_genrecriteria=q{(Songs.Genre LIKE '%'\|\|}.join(q{\|\|'%' OR Songs.G +enre LIKE '%'\|\|},map {"?"} @inc_genres).q{\|\|'%')} unless (scalar(@inc +_genres)==0); my $i_ratingcriteria=qq{Songs.Rating $inc_ratings} unless length($inc_ +ratings)<2; my $i_datecriteria=qq{Songs.Year $inc_year} unless length($inc_year)<2 +; [download] I'm now trying to work out how to either do this while I'm parsing the input text the first time around, or by looping over the `%config`hash recommended by ig. I could use a little bit more help on this. EDIT I think I got it ... `foreach my $k (keys %config) { $config{$k}=[split(/; /, $config{$k})] unless $config{$k}=~/^\s$/; }` [download] Thanks again for the help.	[reply] [d/l] [select]
Re^3: Changing variable names in a loop by ig (Vicar) on Oct 16, 2010 at 20:42 UTC
You could do something like: use strict; use warnings; use Data::Dumper; my %config = map { /^((?:inc\|exc)_\w+)=(.)$/; ( $1, [ split(/\s;\s*/,$2) ] ) } <DATA>; print Dumper(\%config); __DATA__ inc_albums=a; list; of; albums; to; include inc_genres=a; list; of; genres; to; include inc_artists=a; list; of; artists; to; include inc_songs=a; list; of; songs; to; include inc_year=a; list; of; years; to; include exc_albums=a; list; of; albums; to; exclude exc_genres=a; list; of; genres; to; exclude exc_artists=a; list; of; artists; to; exclude exc_songs=a; list; of; songs; to; exclude exc_year=a; list; of; years; to; exclude [download] But I find such code too cryptic and would probably do it more like the following myself: Read more... (5 kB)	[reply] [d/l] [select]