I just learned
Parse::RecDescent yesterday and I wanted to try it. Consider this an example of how not to solve the problem.
use warnings;
use strict;
use Parse::RecDescent;
use Data::Dumper;
my $string = <<END;
JOB ID=EX1J DESC='JOB1'
JOB ID=EX2J DESC='JOB2'
JOB ID=EX3J DESC='JOB3'
JOB ID=EX4J DESC='JOB3'
EX4J PRED EX2J
EX3J PRED EX1J
EX4J PRED EX1J
END
our %data;
my $parser = Parse::RecDescent->new (q{
startrule : jobphrase(s) exphrase(s)
jobphrase : "JOB ID=" ex "DESC=" jobquote
{
$::data{$item[2]}{'desc'} = $item[4];
$::data{$item[2]}{'pred'} ||=[]
}
exphrase : ex "PRED" ex
{
push @{$::data{$item[1]}{'pred'}}, @item[3]
}
jobquote : "'" job "'" {$return = $item[2]}
ex : /EX\dJ/
job : /JOB\d/
});
$parser->startrule($string);
print Dumper \%data;