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#!/usr/bin/perl -w

#
# btcheck
#
# Check the syntax and structure of a single BibTeX database file.
# Currently hardcoded to use the "Bib" structure, which implements
# exactly the structure of BibTeX 0.99.
#
# $Id$
#

use strict;
use Text::BibTeX (':metatypes');

my ($filename, $structure, $bibfile, $entry, %seen_key);
die "usage: btcheck file [structure]\n" unless @ARGV == 1 || @ARGV == 2;
($filename, $structure) = @ARGV;
$structure ||= 'Bib';

$bibfile =  Text::BibTeX::File->new( $filename) or die "$filename: $!\n";
$bibfile->set_structure ($structure);

while ($entry =  Text::BibTeX::Entry->new( $bibfile)) 
{
   next unless $entry->parse_ok and $entry->metatype == BTE_REGULAR;
   my $key = $entry->key;
   $entry->warn ("repeated entry key \"$key\"") if $seen_key{$key};
   $seen_key{$key} = 1;
   $entry->check;
}