NAME - Utility to generate UML class diagrams from Perl source or runtime


    # generate a PNG file for the Foo module:
    $ -M Foo -o foo.png -p "^Foo::"

    # generate an SVG image file which is vectorized and super clear:
    $ --without-inherited-methods -o foo.svg -r lib/

    # generate the dot source file:
    $ -M Foo -o

    $ -o bar.gif -p "Bar::|Baz::" lib/ lib/*/*.pm

    $ -o blah.png -p Blah -r ./blib

    $ --without-inherited-methods -o blah.png -r lib


This is a simple command-line frontend for the UML::Class::Simple module.

I'll illustrate the usage of this tool via some real-world examples.

Draw Stevan's Moose

  $ -M Moose -o samples/moose_small.png -p "^(Class::MOP|Moose::)" -s 4x8

This command will generate a simple class diagram in PNG format for the Moose module with classes having names matching the regex "^(Class::MOP|Moose::)". The image's width is 4 inches while its height is 8 inches.

We need the -M option here since needs to preload Moose into the memory so as to inspect it at runtime.

The graphical output is given below:

(See also

Yes, the image above looks very fuzzy since the whole stuff is huge. If you strip the -s option, then the resulting image will enlarge automatically:

  $ -M Moose -o samples/moose_big.png -p "^(Class::MOP|Moose::)"

The image obtained is really really large, I won't show it here, but you can browse it in your favorite picture browser from

Before trying out these commands yourself, please make sure that you have Moose already installed. (It's also on CPAN, btw.)

Perl libraries that use Moose

Perl classes that inherit from Moose will have tons of "meta methods" like before, after, has, and meta, which are not very interesting while plotting the class diagram. So it's common practice to specify the --without-inherited-methods option like this:

  $ --without-inherited-methods -o uml.png -r lib

If you also add --moose-roles, extra edges will appear in the graph, in an alternate color, representing the relationships between roles and their consumers.

Draw Alias's PPI

  $ -M PPI -o samples/ppi_small.png -p "^PPI::" -s 10x10

(See also

Or the full-size version:

  $ -M PPI -o samples/ppi_big.png -p "^PPI::"


BTW, PPI is a prerequisite of this module.

Draw from UML::Class::Simple's Test Suite

  $ -M FAST -o samples/fast.png -s 5x10 -r t/FAST/lib

This is an example of drawing classes contained in Perl source files.

Draw Modules of Your Own

Suppose that you're a CPAN author too and want to produce a class diagram for all the classes contained in your lib/ directory. The following command can do all the hard work for you:

    $ -o mylib.png -r lib

or just plot the packages in the specified .pm files:

    $ -o a.png lib/ lib/bar/

or even specify a pattern (in perl regex) to filter out the packages you want to draw:

    $ -o a.png -p "^Foo::" lib/

Quite handy, isn't it? ;-)


Never feed plain module names to, for intance,

  $ Scalar::Defer  # DO NOT DO THIS!

will lead you to the following error message:

  error: input file Scalar::Defer not found.

Use -M and -p options to achieve your goals:

  $ -M Scalar::Defer -p "Scalar::Defer"

In this example, I must warn you that you may miss the packages which belong to Scalar::Defer but don't have "Scalar::Defer" in their names. I'm sorry for that. is not that smart.

The safest ways to do this are

  1. Don't specify the -p regex option and generate a large image which shows every classes including CORE modules, figure out the appropriate class name pattern yourself, and rerun with the right regex pattern.

  2. Grab the Scalar::Defer's tarball, and do something like this:

       $ -r Scalar-Defer-0.07/lib

It's worth mentioning that when .pl or .pm files are passing as the command line arguments, only the classes defined in these files will be drawn. This is a feature. :)

For .pm files on your disk, simply pass them as the command line arguments. For instance:

   $ -o bar.gif lib/ lib/*/*.pm

or tell to iterate through the directories for you:

   $ -o blah.png -r ./lib


--color color
-c color

Sets the node color. Defaults to #f1e1f4.

You can either specify RGB values like #rrggbb in hex form, or color names like "grey" and "red".

--dot path

Tell it where the graphviz "dot" program is

--exclude path
-E path

excludes modules that were installed to path from the drawing. multiple -E options are supported.


Shows the help message.

--include path
-I path

Draws only the classes that were installed to path in the drawing. multiple -I options are supported.

-M module

Preloads the module which contains the classes you want to depict. For example,

    $ -M PPI -o ppi.png -p "^PPI::"

Multiple -M options are accepted. For instance:

    $ -M Foo -M Bar::Baz -p "Class::"

Don't display method names in the output.


Don't show the inheritance relationships in the output. Not terribly useful unless you are using Moose and asking for --moose-roles.

--out outfile
-o outfile

Specifies the output file name. Note that the file extension will be honored. If you specify "-o foo.png", a PNG image named foo.png will be generated, and if you specify "-o", the dot source file named will be obtained. If you specify "-o foo.xmi", the XMI model file will be generated. Likewise, "-o foo.yml" will lead to a YAML file holding the whole internal DOM data.

A typical usage is as follows:

    $ -o foo.yml lib/

    # ...edit the foo.yml so as to adjust the class info
    # feed the updated back
    $ -o foo.yml

    # ...edit the so as to adjust the graphviz dot source
    # now feed the updated back
    $ -o foo.png

You see, allows you to control the behaviors at several different levels. I really like this freedom, since tools can't always do exactly what I want.

If no -o option was specified, a.png will be assumed.

--pattern regex
-p regex

Specifies the pattern (perl regex) used to filter out the class names to be drawn.


Shows public methods only.


Processes subdirectories of input directories recursively.


If a package appears to be a Moose::Role, determine which other packages consume that role, and add that information to the graph in a different color from the inheritance hierarchy. Depending on the particular input classes and your personal artistic tastes, this may substantially alter the usefulness and/or cleanliness of the resulting diagram. For large package hierarchies, it is recommended to combine this with --no-inheritance.

-s <w>x<h>

Specifies the width and height of the resulting image. For example:

    -s 3.6x7

    --size 5x6

where the unit is inches instead of pixels.


Do not show methods from parent classes.

All inherited and imported methods will be excluded. Note that if a method is overridden in the current subclass, it will still be included even if it appears in one of its ancestors.


  • If the user passes plain module names like "Foo::Bar", then its (and only its) ancestors and subclasses will be drawn. (This is suggested by Christopher Malon.)


Yichun Zhang <>, Maxim Zenin <>


Copyright 2006-2017 by Yichun Zhang. All rights reserved.

This library is free software; you can redistribute it and/or modify it under the same terms as perl itself.