How do I change this to “idiomatic” Perl?

Question

I am beginning to delve deeper into Perl, but am having trouble writing \"Perl-ly\" code instead of writing C in Perl. How can I change the following code to use more Perl idiom

Answer 1

You're getting several suggestions regarding syntax, but I would also suggest a more modular approach, if for no other reason that code readability. It's much easier to come up to speed on code if you can perceive the big picture before worrying about low-level details.

Your primary method might look like this.

sub create_matrix {
    my $self = shift;
    $self->create_2d_array_of_scores;
    $self->fill_out_first_row;
    $self->fill_out_other_rows;
}

And you would also have several smaller methods like this:

n_of_rows
n_of_cols
create_2d_array_of_scores
fill_out_first_row
fill_out_other_rows

And you might take it even further by defining even smaller methods -- getters, setters, and so forth. At that point, your middle-level methods like create_2d_array_of_scores would not directly touch the underlying data structure at all.

sub matrix      { shift->{score_matrix} }
sub gap_cost    { shift->{gap_cost}     }

sub set_matrix_value {
    my ($self, $r, $c, $val) = @_;
    $self->matrix->[$r][$c] = $val;
}

# Etc.