Read line from file

Note! This site is about Perl 6.
If you are looking for a solution for Perl 5, please check out the Perl 5 tutorial.

As in other high level languages one has to open a file in order to read from it or to write to it. In Perl 6 it is done by the open() function imported from the IO class. It can receive several parameter but these two are very important: The name of the file and the mode. In order to open a file for reading the mode need to be :r. The function either returns a file handle that should be placed in a scalar variable or throws an exception in case of failure.

$fh = open $filename, :r

Once we have an open file handler we can use the get method ($fh.get) to read one line from the given file.

One could read many lines using consecutive calls to the get method but there are better ways to do that.

The specifications of all the IO of Perl 6 can be found in S32-setting-library/IO.pod

tutorial/files/read_one_line.p6

#!/usr/bin/env perl6
use v6;

my $filename = $*PROGRAM-NAME;

my $fh = open $filename;
my $line = $fh.get;
say $line;

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