📘 Working with files and directories in Perl 6

To get the content of a file, use the slurp built-in function, which reads the whole file and returns a string.

say slurp "file.txt";

The function that does the opposite is called spurt, it writes the string to a file.

Let us implement the Unix’s cp command in Perl 6.

my ($source, $dest) = @*ARGS; 

my $data = slurp $source;
spurt $dest, $data;

By default, either a new destination file will be created or rewritten if it already exists. You can open the file in the append mode by adding the :append value in the third argument:

spurt $dest, $data, :append;

Another mode, :createonly, generates an error if the file exists.

spurt $dest, $data, :createonly;

Both slurp and spurt accept an argument with the encoding name:

my ($source, $dest) = @*ARGS; 

my $data = slurp $source, enc => 'UTF-8';
spurt $dest, $data, enc => 'UTF-16';

The Str class inherits (from the Cool class) the IO method that returns an object of the IO::Path class. It contains some useful information about the file.

For example, this is how you can get the absolute path to a local file:

say 'file.txt'.IO.abspath;

The IO.dir method prints the content of a directory:

say '.'.IO.dir;

The IO.extension method returns an extension of a file:

say $filename.IO.extension;
say $filename.IO.extension;

Finally, there are one-letter named methods for making checks of the file’s or directory’s existence or checking its properties:

say 1 if 'file.txt'.IO.e; # same as -e 'file.txt' in Perl 5 (file exists)
say 1 if 'file.txt'.IO.f; # -f (is a file)
say 1 if '..'.IO.d;       # -d (is a directory)

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