for loop with .lines

gistfile1.txt

use Slang::Tuxic;
use Text::CSV;
use File::Find;

my $csv_line = Text::CSV.new (eol => "\n");
my $cols = 49;

my @IO-object-list = find(:dir</home/user1/documents/animals>, :type<file>, :name(/armadillos_201<[4..8]>.*\.csv/));

for @IO-object-list -> $IO-object {
    my $out = $IO-object.path.subst(/\.csv/, '_edit.csv');
    my $fh = $out.IO.open: :w;
    my $contents = $IO-object.slurp;
    # for $contents.lines() -> Str $line {    # this works
    for $contents.lines -> Str $line {        # this doesn't
        if $csv_line.parse($line) {
            if $csv_line.strings.elems lt $cols {
                my $pad = ',' x ( $cols - $csv_line.strings.elems );
                $fh.put: $line ~ $pad;
            } else { $fh.put: $line }
        }
    }
    $fh.close;
}

user1@laptop:~/CommaProjects/animals> perl6 animals.p6
===SORRY!=== Error while compiling /home/user1/CommaProjects/animals.p6
Unsupported use of -> as postfix; in Perl 6 please use either . to call a method, or whitespace to delimit a pointy block
at /home/user1/CommaProjects/animals.p6:22 [<<< this not actual line no]
------> for $contents.lines ->⏏ Str $line {
expecting any of:
dotty method or postfix
postfix