Easiest way to open a text file and read it into an array with Perl

Question

Adding a standard Perl file open function to each script I have is a bit annoying:

sub openfile{
    (my $filename) = @_;
    open FILE,\"$filename\" or die          


        

Answer 1

I think this is what you are looking for

File::Slurp

Answer 2

Also have a look at Perl6::Slurp which implements the Perl6 version of slurp and is recommended in the "Perl Best Practices" book.

Some examples....

my @lines         = slurp 'filename';
my @lines_chomped = slurp 'filename', { chomp => 1 };
my @lines_utf8    = slurp 'filename', { utf8  => 1 };

Answer 3

You've gotten the general techniques, but I want to put in that Perl sort of discourages you from doing that because it's very often the case that you can do the same thing you're doing one-line-at-a-time, which is inherently far more efficient.

Answer 4

You have several options, the classic do method:

my @array = do {
    open my $fh, "<", $filename
        or die "could not open $filename: $!";
    <$fh>;
};

The IO::All method:

use IO::All;

my @array = io($filename)->slurp;

The File::Slurp method:

use File::Slurp;

my @array = read_file($filename);

And probably many more, after all TIMTOWTDI.

Answer 5

I would recommend an object oriented approach that does not requires modules outside the CORE distribution and will work anywhere:

use strict;
use warnings;
use IO::File;
my $fh = IO::File->new("< $file");

foreach ($fh->getlines) {
    do_something($_);
}
$fh->close

Answer 6

that is the famous "slurp mode":

  my @lines = <FILEHANDLE> ;

you may also see Perl Slurp Ease