Eight Useful Modules

A quick introduction into the following useful modules:

• File::Operations (save_file, load_file, remove_dir and many more)
• Text::WikiText (this whole abstract is written in WikiText)
• Data::NeatDump (neater than Data::Dumper)
• Data::NeatFormat (show scalars and lists nicely)
• Date::TimeFormat (there is more than one way to do it)
• Exception (C++/Java like syntax try/catch/throw with call stack)
• Parse::PerlConf (write configuration files using perl syntax)
• Parse::Copec64 (store any complex perl data using letters and digits only)

BTW, the source of this slide is in Text::WikiText format.

File::Operations

Saving file

	save_file($filename, $content);
	save_file($filename, $content_ref);
	save_file($filename, \@lines);
	save_file($filename, $content, create_dirs => 1, is_utf8 => 0);

	append_file($filename, $content);

Loading file

	my $content = load_file($filename);
	load_file($filename, \$content);
	load_file($filename, \@lines);
	my $content = load_file($filename, is_utf8 => 1);

File::Operations (cont.)

Other file-system operations

	make_path("/tmp/my-own/dir0");
	make_dir("/tmp/my-own/dir", 0711);
	copy_file("/etc/issue", "/tmp/my-own/dir/issue");
	remove_file("/tmp/my-own/dir/issue2");
	clean_dir("/tmp/my-own/dir");  # no effect, empty already
	remove_dir("/tmp/my-own");

Saving/loading tabular fields (TAB separated lines)

	save_field_file($filename, $lines_of_fields);
	my $lines_of_fields2 = load_field_file($filename);

	save_field_file($filename, $table, create_dirs => 1, delim => ',');
	my $table2 = load_field_file($filename, delim => ',');

Text::WikiText

Simple human-readable syntax

This is a new wiki text. Write bold words, italic words, underlined words and more. Paragraphs are delimited by an empty line.

See syntax specification for the exact rules.

Tables

Tables	are	simple
1	2	3
4	two columns
5	6	7

Another table:

HTTP	codes
301	Moved
302	Found
403	Forbidden
404	Not found
500	Internal Error

See the source of this slide.

Text::WikiText (cont.)

Lists

There are several kinds of lists

• regular

• numbered, like this:

  1. good
  2. bad
  3. ugly

• may be nested, if needed

More examples

	preformatted text
		as is

if ($condition) {
	print "This is a code.";
}

Quotations:

A language that doesn't affect the way you think about programming, is not worth knowing.

-- Alan Perlis

See the source of this slide.

Data::NeatDump

    use Data::NeatDump;

    print dump($long_struct);
    print Dump($data1, $data2, $data3);

    [
        "First element",
        {
            key1 => "Short string",
            key2 => "Another string",
        },
        [
            2.71828182845905,
            3.14159265358979,
        ],
    ]

Why not Data::Dumper?

Several reasons:

• shorter usage
• cleaner API
• nicer and more structured output by default
• hash keys are sorted
• cuts long structures using ellipsis
• but: for neat presentation, not general serialization

Thank you

References:

• Podius CMS is the origin of these modules
• Documentation of these modules
• Useful Perl Modules - presentation online