I have a list of strings (30,000+) which are a collection of statements. Logically, Parse::RecDescent is the tool to use to parse the string to gather the data, but I just can't get my head round the construction of the grammar specification.
The following code is building a big list of blessed nodes, however I just can't figure out how to actually create a more useful data-structure
(All I want are the Year, Vol & Iss values)
#!/usr/bin/perl
use strict;
use warnings;
use Parse::RecDescent;
use Data::Dumper;
my $string1 = '2006 - v. 1 (1-2), 2007 - v. 2 (1-4), 2008 - v. 3 (1-4), 2009 - v. 4 (1-4), 2010 - v. 5 (1-4), 2011 - v. 6 (1-2), 2012 - v. 7 (1, 4), 2013/2014 - v. 8 (1-4), 2014 - v. 9 (1, 3)';
my $string2 = 'v.35(1,2),v.36(1,2),v.33(1,2),v.34(1,2),v.39(1,2),v.37(1,2),v.38(1,2),v.43(1,2),v.42(1,2),v.41(1,2),v.40(1,2),v.22(),v.23(),v.24(),v.25(1),v.26(),v.27(),v.28(1,2),v.29(1,2),v.3(),v.2(1,2),v.1(1,2),v.30(),v.7(),v.6(),v.32(1,2),v.5(),v.4(),v.31()';
my $string3 = '1820/1825 - v. 1 (1-2), 1821/1825 - v. 2 (3-4), 1821/1826 - v. 3 (5-6), 1821 - v. 4 (7-8), 1822 - v. 5 (9-10), 1823 - v. 6 (11-12), 1823 - v. 7 (13-14), 1823 - v. 8 (15-16), 1824 - v. 9 (17-18)';
my $data = {}; # Edit: Added hash-ref to show alternate testing
my $grammar = q {
<autotree>
Holdings : Node(s /,/)
Node : When(?) Volume Issue { $data->{ $item{when} } = [ $item{Vol}, $item{Iss} ] } # Edit: Action Added - This was one option I tried
When : Years | Year { $arg[0] = $item{When} }
Years : Year '/' Year
Year : /\\d{4}/ { $item[1] } # Edit: Action Added - This was another option I tried
Volume : /v\\.\\s*/ Vol { $arg[1] = $item{Vol} } # Edit: Add commet "This was blindly flailing to work out how to get variable data
Vol : /\\d+/
Issue : /\\s*\(/ Iss ')' { $arg[2] = $item{Iss} }
Iss : /[\\d+\\-\\,]*/
};
my $parser = Parse::RecDescent->new($grammar);
foreach my $string ( ($string1, $string2, $string3) ) {
$string =~ s/\s+\-\s+//g;
print "$string\n";
my $output = $parser->Holdings($string);
print Dumper $output;
}
On a side-note, how do I write the grammar statement so I don't need the substitution in the loop?
make_parser.pl:
#!/usr/bin/perl
use strict;
use warnings;
use Parse::RecDescent qw( );
my $grammar = <<'__END_OF_GRAMMAR__';
{
use strict;
use warnings;
}
parse : Holdings /\Z/ { $item[1] }
Holdings : Node(s /,/) #{ $item[-1] }
Node : When /-?/ Node_ { [ $item[1], @{$item[3]} ] }
| Node_ { [ undef, @{$item[1]} ] }
Node_ : Volume Issue { [ $item[1], $item[2] ] }
When : Year When_[ $item[1] ] #{ $item[-1] }
When_ : '/' Year { $arg[0] . '/' . $item[2] }
| { $arg[0] }
Year : /\d{4}/ #{ $item[-1] }
Volume : /v\.\s*/ /\d+/ #{ $item[-1] }
Issue : '(' /[^)]*/ ')' { $item[2] =~ s/\s//gr }
__END_OF_GRAMMAR__
Parse::RecDescent->Precompile($grammar, 'Grammar')
or die("Bad grammar\n");
a.pl:
#!/usr/bin/perl
use strict;
use warnings;
use Grammar qw( );
#$::RD_TRACE = 1;
my $parser = Grammar->new();
while (<DATA>) {
chomp;
my $recs = $parser->parse($_)
or do { warn("Bad data at line $.\n");
next;
};
print("For: $_\n");
for my $rec (@$recs) {
printf(" %s | %s | %s\n",
defined($rec->[0]) ? $rec->[0] : '[undef]',
$rec->[1],
$rec->[2],
);
}
}
__DATA__
2006 - v. 1 (1-2), 2007 - v. 2 (1-4), 2008 - v. 3 (1-4), 2009 - v. 4 (1-4), 2010 - v. 5 (1-4), 2011 - v. 6 (1-2), 2012 - v. 7 (1, 4), 2013/2014 - v. 8 (1-4), 2014 - v. 9 (1, 3)
v.35(1,2),v.36(1,2),v.33(1,2),v.34(1,2),v.39(1,2),v.37(1,2),v.38(1,2),v.43(1,2),v.42(1,2),v.41(1,2),v.40(1,2),v.22(),v.23(),v.24(),v.25(1),v.26(),v.27(),v.28(1,2),v.29(1,2),v.3(),v.2(1,2),v.1(1,2),v.30(),v.7(),v.6(),v.32(1,2),v.5(),v.4(),v.31()
1820/1825 - v. 1 (1-2), 1821/1825 - v. 2 (3-4), 1821/1826 - v. 3 (5-6), 1821 - v. 4 (7-8), 1822 - v. 5 (9-10), 1823 - v. 6 (11-12), 1823 - v. 7 (13-14), 1823 - v. 8 (15-16), 1824 - v. 9 (17-18)
Output:
$ perl make_parser.pl
$ perl a.pl
For: 2006 - v. 1 (1-2), 2007 - v. 2 (1-4), 2008 - v. 3 (1-4), 2009 - v. 4 (1-4), 2010 - v. 5 (1-4), 2011 - v. 6 (1-2), 2012 - v. 7 (1, 4), 2013/2014 - v. 8 (1-4), 2014 - v. 9 (1, 3)
2006 | 1 | 1-2
2007 | 2 | 1-4
2008 | 3 | 1-4
2009 | 4 | 1-4
2010 | 5 | 1-4
2011 | 6 | 1-2
2012 | 7 | 1,4
2013/2014 | 8 | 1-4
2014 | 9 | 1,3
For: v.35(1,2),v.36(1,2),v.33(1,2),v.34(1,2),v.39(1,2),v.37(1,2),v.38(1,2),v.43(1,2),v.42(1,2),v.41(1,2),v.40(1,2),v.22(),v.23(),v.24(),v.25(1),v.26(),v.27(),v.28(1,2),v.29(1,2),v.3(),v.2(1,2),v.1(1,2),v.30(),v.7(),v.6(),v.32(1,2),v.5(),v.4(),v.31()
[undef] | 35 | 1,2
[undef] | 36 | 1,2
[undef] | 33 | 1,2
[undef] | 34 | 1,2
[undef] | 39 | 1,2
[undef] | 37 | 1,2
[undef] | 38 | 1,2
[undef] | 43 | 1,2
[undef] | 42 | 1,2
[undef] | 41 | 1,2
[undef] | 40 | 1,2
[undef] | 22 |
[undef] | 23 |
[undef] | 24 |
[undef] | 25 | 1
[undef] | 26 |
[undef] | 27 |
[undef] | 28 | 1,2
[undef] | 29 | 1,2
[undef] | 3 |
[undef] | 2 | 1,2
[undef] | 1 | 1,2
[undef] | 30 |
[undef] | 7 |
[undef] | 6 |
[undef] | 32 | 1,2
[undef] | 5 |
[undef] | 4 |
[undef] | 31 |
For: 1820/1825 - v. 1 (1-2), 1821/1825 - v. 2 (3-4), 1821/1826 - v. 3 (5-6), 1821 - v. 4 (7-8), 1822 - v. 5 (9-10), 1823 - v. 6 (11-12), 1823 - v. 7 (13-14), 1823 - v. 8 (15-16), 1824 - v. 9 (17-18)
1820/1825 | 1 | 1-2
1821/1825 | 2 | 3-4
1821/1826 | 3 | 5-6
1821 | 4 | 7-8
1822 | 5 | 9-10
1823 | 6 | 11-12
1823 | 7 | 13-14
1823 | 8 | 15-16
1824 | 9 | 17-18