CODEWITHSUNDEEP
perl
Kenster
Kenster

Reputation: 25439

Any sequence of \r or \n as a line separator?

I'm maintaining a Perl script (Perl 5.10 on Linux) which needs to process a file line-by-line while being as flexible as possible regarding line separator characters. Any sequence of newlines and/or carriage return characters should mark the end of a line. Blank lines in the file aren't significant. For example, all of these should yield two lines:

FOO\nBAR        FOO\rBAR
FOO\r\nBAR      FOO\n\rBAR
FOO\r\n\r\r\r\n\n\nBAR

It doesn't look like it's possible to get this behavior through PerlIO or by setting $/. The files aren't large, so I suppose I could just read the whole file into memory and then split it with a regular expression. Is there are more clever way to do this in Perl?

Upvotes: 0

Views: 178

Answers (1)

Miller
Miller

Reputation: 35208

Just slurp the file and use split:

use strict;
use warnings;
use autodie;

use Data::Dump;

my @data = (
    "FOO\nBAR",
    "FOO\rBAR",
    "FOO\r\nBAR",
    "FOO\n\rBAR",
    "FOO\r\n\r\r\r\n\n\nBAR",
);

for my $filedata (@data) {
    dd $filedata;

    open my $fh, "<", \"$filedata";
    local $/;
    for my $line (split /[\n\r]+/, <$fh>) {
        print "   $line\n";
    }
}

Outputs:

"FOO\nBAR"
   FOO
   BAR
"FOO\rBAR"
   FOO
   BAR
"FOO\r\nBAR"
   FOO
   BAR
"FOO\n\rBAR"
   FOO
   BAR
"FOO\r\n\r\r\r\n\n\nBAR"
   FOO
   BAR

Upvotes: 3

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