This works for me: csv (in => 'quux.csv', filter => {1 => sub { !/^#/ }});

Unfortunately that also filters lines whose first field is "#foo" (with the quotes). I remember Tux recently saying filtering before parsing wasn't supported, though I'm having trouble finding the reference at the moment (it could have been in the chatterbox too*). It may be a bit tricky because this is valid CSV too:

abc,"d
#e
f",ghi
[download]

(That's one row, ["abc", "d\n#e\nf", "ghi"].)

* Update: I looked again and I think it must have been in the chatterbox; I do distinctly remember someone having a similar question recently...

The meta info knows whether the field was quoted or not.

#!/usr/bin/perl
use warnings;
use strict;

use Text::CSV_XS;

my $csv = 'Text::CSV_XS'->new ({ binary         => 1,
                                 auto_diag      => 1,
                                 keep_meta_info => 1 });
open my $in, '<:encoding(utf8)', shift or die $!;
while (my $row = $csv->getline($in)) {
    next if $row->[0] =~ m/^#/ && ! $csv->is_quoted(0);

    $csv->say(*STDOUT, $row);
}
[download]

Tested with

#x,y,z skip
abc,"d
#e
f",ghi keep
#comment skip
a,b,c,#xyz keep
"#foo",x,y,z keep
[download]

map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]

The meta info knows whether the field was quoted or not.

True, though AFAICT the meta_info doesn't seem to keep track of escaped characters:

use warnings;
use strict;
use Data::Dump;
use Text::CSV;

my $csv = Text::CSV->new({ binary=>1, auto_diag=>2,
    keep_meta_info=>1, escape_char=>"\\" });
while ( my $row = $csv->getline(*DATA) ) {
    dd $row, $csv->meta_info;
}
$csv->eof or $csv->error_diag;

__DATA__
foo,bar
"#foo","bar"
#foo,bar
\#foo,bar
[download]

In this special case it looks like there won't be portuguese words starting with a "#", so it would work for OP, as long as he is aware of it

In this special case it looks like there won't be portuguese words starting with a "#", so it would work for OP, as long as he is aware of it

True as well :-) (I guess this is more about the generic case of filtering comments from CSV files.)

If you only want the first lines starting with # to be filtered, that is indeeed what filter is for:

use Data::Peek;
use Text::CSV_XS qw( csv );

my $r = 0;
my $aoa = csv (in => *DATA, filter => sub { $_[1][0] =~ m/^\s*#/ ? $r 
+: ++$r; });
DDumper $aoa;
__END__
# This is comment
# and so is this
# and this
a,b,c
#but,not,this
1,2,3
[download]

-->

[
    [   'a',
        'b',
        'c'
        ],
    [   '#but',
        'not',
        'this'
        ],
    [   '1',
        '2',
        '3'
        ]
    ]
[download]

Thanks! I see you're filtering lines beginning with # when they occur at the beginning of the file; the way I understood the OP's sample data is that the comments can occur anywhere. And my worry was that, even though in the OP's data this is probably not the case, filter-based solutions will remove lines that may actually not be comments, and I wasn't sure if there was a easy solution for this?

use warnings;
use strict;
use Data::Peek;
use Text::CSV_XS qw/csv/;

DDumper csv( in=>*DATA, escape_char=>"\\",
    filter => sub { $_[1][0] !~ m/^\s*#/ });

__DATA__
# This is a comment
a,b,c

# Also a comment
x,y,z
"#not",a,comment
\#also,not,"a comment"
[download]

Output:

[
    [   'a',
        'b',
        'c'
        ],
    [   ''
        ],
    [   'x',
        'y',
        'z'
        ],
    [   ''
        ]
    ]
[download]

So more or like like this:?

DDumper csv (
    in     => *DATA,
    sep    => "|",
    filter => sub {
        $_[1][0] =~ m/^\s*#/ && @{$_[1]} == 1 ? 0 : 1;
        },
    );
[download]

Which would not even need a ternary if slightly rewritten


Enjoy, Have FUN! H.Merijn