Perl 6 script to convert dates to ISO8601

date-format-conversion.p6

#!/usr/bin/env perl6

use v6.d;

=begin DESCRIPTION

Given a newline-delimited file of mm/dd/yyyy, write a newline-delimited
file of yyyy-mm-dd.

=end DESCRIPTION

my $in = 'dates.txt'.IO;
my $out = 'dates_iso_8601.txt'.IO;

$out.spurt('');

for $in.lines {
    m/
        $<month> = (\d ** 1..2)
        \/
        $<day> = (\d ** 1..2)
        \/
        $<year> = (\d ** 4)
    /;

    my $date = Date.new($<year>, $<month>, $<day>);

    $out.spurt("{ $date.yyyy-mm-dd }\n", :append);
}

Thank you so much for the code review, @lizmat! I've seen the $*OUT trick but have yet to try it (and didn't think to in this context), so I will check it out. 😎

Thank you especially for all of your hard work on the Perl 6 project; I am a huge fan and I am extremely grateful for how the language is coming along.