How to read gz file line by line in Perl6

Question

I'm trying to read a huge gz file line by line in Perl6.

I'm trying to do something like this

my $file = 'huge_file.gz';
for $file.IO.lines -> $line {
    say $line;
}

But this give error that I have a malformed UTF-8. I can't see how to get this to read gzipped material from the help page https://docs.perl6.org/language/unicode#UTF8-C8 or https://docs.perl6.org/language/io

I want to accomplish the same thing as was done in Perl5: http://blog-en.openalfa.com/how-to-read-and-write-compressed-files-in-perl

How can I read a gz file line by line in Perl6?

thanks

Answer 1

I would recommend using the module Compress::Zlib for this purpose. You can find the readme and code on github and install it with zef install Compress::Zlib.

This example is taken from the test file number 3 titled "wrap":

use Test;
use Compress::Zlib;

gzspurt("t/compressed.gz", "this\nis\na\ntest");

my $wrap = zwrap(open("t/compressed.gz"), :gzip);
is $wrap.get, "this\n", 'first line roundtrips';
is $wrap.get, "is\n", 'second line roundtrips';
is $wrap.get, "a\n", 'third line roundtrips';
is $wrap.get, "test", 'fourth line roundtrips';

This is probably the easiest way to get what you want.