#
# This software is Copyright 2005 by Elsevier Inc.  You may use it
# under the terms of the license at http://perl.plover.com/hop/LICENSE.txt .
#



###
### query-composable
###

## Chapter 7 section 4

# usage: $dbh->query(fieldname, value)
# returns all records for which (fieldname) matches (value)
sub query {
  my $self = shift;
  my ($field, $value) = @_;
  my $fieldnum = $self->{FIELDNUM}{uc $field};
  return unless defined $fieldnum;
  my $fh = $self->{FH};
  seek $fh, 0, 0;
  <$fh>;                # discard header line
  my $position = tell $fh;
  my $recno = 0;

  return sub {
    local $_;
    seek $fh, $position, 0;
    while (<$fh>) {
      $recno++;
      $position = tell $fh;         
      my @fields = split $self->{FIELDSEP};
      my $fieldval = $fields[$fieldnum];
      return [$recno, @fields] if $fieldval eq $value;
    }
    return;
  };
}


## Chapter 7 section 4

# I LIKE PIE