Ubuntu Manpage: Module::Build - Build and install Perl modules

Provided by: perl-doc_5.18.2-2ubuntu1.7_all

NAME

       Module::Build - Build and install Perl modules

SYNOPSIS

       Standard process for building & installing modules:

         perl Build.PL
         ./Build
         ./Build test
         ./Build install

       Or, if you're on a platform (like DOS or Windows) that doesn't require the "./" notation,
       you can do this:

         perl Build.PL
         Build
         Build test
         Build install

DESCRIPTION

       "Module::Build" is a system for building, testing, and installing Perl modules.  It is
       meant to be an alternative to "ExtUtils::MakeMaker".  Developers may alter the behavior of
       the module through subclassing in a much more straightforward way than with "MakeMaker".
       It also does not require a "make" on your system - most of the "Module::Build" code is
       pure-perl and written in a very cross-platform way.  In fact, you don't even need a shell,
       so even platforms like MacOS (traditional) can use it fairly easily.  Its only
       prerequisites are modules that are included with perl 5.6.0, and it works fine on perl
       5.005 if you can install a few additional modules.

       See "MOTIVATIONS" for more comparisons between "ExtUtils::MakeMaker" and "Module::Build".

       To install "Module::Build", and any other module that uses "Module::Build" for its
       installation process, do the following:

         perl Build.PL       # 'Build.PL' script creates the 'Build' script
         ./Build             # Need ./ to ensure we're using this "Build" script
         ./Build test        # and not another one that happens to be in the PATH
         ./Build install

       This illustrates initial configuration and the running of three 'actions'.  In this case
       the actions run are 'build' (the default action), 'test', and 'install'.  Other actions
       defined so far include:

         build                          manifest
         clean                          manifest_skip
         code                           manpages
         config_data                    pardist
         diff                           ppd
         dist                           ppmdist
         distcheck                      prereq_data
         distclean                      prereq_report
         distdir                        pure_install
         distinstall                    realclean
         distmeta                       retest
         distsign                       skipcheck
         disttest                       test
         docs                           testall
         fakeinstall                    testcover
         help                           testdb
         html                           testpod
         install                        testpodcoverage
         installdeps                    versioninstall

       You can run the 'help' action for a complete list of actions.

GUIDE TO DOCUMENTATION

       The documentation for "Module::Build" is broken up into sections:

       General Usage (Module::Build)
           This is the document you are currently reading. It describes basic usage and
           background information.  Its main purpose is to assist the user who wants to learn how
           to invoke and control "Module::Build" scripts at the command line.

       Authoring Reference (Module::Build::Authoring)
           This document describes the structure and organization of "Module::Build", and the
           relevant concepts needed by authors who are writing Build.PL scripts for a
           distribution or controlling "Module::Build" processes programmatically.

       API Reference (Module::Build::API)
           This is a reference to the "Module::Build" API.

       Cookbook (Module::Build::Cookbook)
           This document demonstrates how to accomplish many common tasks.  It covers general
           command line usage and authoring of Build.PL scripts.  Includes working examples.

ACTIONS

There are some general principles at work here. First, each task when building a module
is called an "action". These actions are listed above; they correspond to the building,
testing, installing, packaging, etc., tasks.

Second, arguments are processed in a very systematic way. Arguments are always key=value
pairs. They may be specified at "perl Build.PL" time (i.e. "perl Build.PL
destdir=/my/secret/place"), in which case their values last for the lifetime of the
"Build" script. They may also be specified when executing a particular action (i.e.
"Build test verbose=1"), in which case their values last only for the lifetime of that
command. Per-action command line parameters take precedence over parameters specified at
"perl Build.PL" time.

The build process also relies heavily on the "Config.pm" module. If the user wishes to
override any of the values in "Config.pm", she may specify them like so:

perl Build.PL --config cc=gcc --config ld=gcc

The following build actions are provided by default.

build
[version 0.01]

If you run the "Build" script without any arguments, it runs the "build" action, which
in turn runs the "code" and "docs" actions.

This is analogous to the "MakeMaker" make all target.

clean
[version 0.01]

This action will clean up any files that the build process may have created, including
the "blib/" directory (but not including the "_build/" directory and the "Build"
script itself).

code
[version 0.20]

This action builds your code base.

By default it just creates a "blib/" directory and copies any ".pm" and ".pod" files
from your "lib/" directory into the "blib/" directory. It also compiles any ".xs"
files from "lib/" and places them in "blib/". Of course, you need a working C
compiler (probably the same one that built perl itself) for the compilation to work
properly.

The "code" action also runs any ".PL" files in your lib/ directory. Typically these
create other files, named the same but without the ".PL" ending. For example, a file
lib/Foo/Bar.pm.PL could create the file lib/Foo/Bar.pm. The ".PL" files are processed
first, so any ".pm" files (or other kinds that we deal with) will get copied
correctly.

config_data
[version 0.26]

...

diff
[version 0.14]

This action will compare the files about to be installed with their installed
counterparts. For .pm and .pod files, a diff will be shown (this currently requires a
'diff' program to be in your PATH). For other files like compiled binary files, we
simply report whether they differ.

A "flags" parameter may be passed to the action, which will be passed to the 'diff'
program. Consult your 'diff' documentation for the parameters it will accept - a good
one is "-u":

./Build diff flags=-u

dist
[version 0.02]

This action is helpful for module authors who want to package up their module for
source distribution through a medium like CPAN. It will create a tarball of the files
listed in MANIFEST and compress the tarball using GZIP compression.

By default, this action will use the "Archive::Tar" module. However, you can force it
to use binary "tar" and "gzip" executables by supplying an explicit "tar" (and
optional "gzip") parameter:

./Build dist --tar C:\path\to\tar.exe --gzip C:\path\to\zip.exe

distcheck
[version 0.05]

Reports which files are in the build directory but not in the MANIFEST file, and vice
versa. (See manifest for details.)

distclean
[version 0.05]

Performs the 'realclean' action and then the 'distcheck' action.

distdir
[version 0.05]

Creates a "distribution directory" named "$dist_name-$dist_version" (if that directory
already exists, it will be removed first), then copies all the files listed in the
MANIFEST file to that directory. This directory is what the distribution tarball is
created from.

distinstall
[version 0.37]

Performs the 'distdir' action, then switches into that directory and runs a "perl
Build.PL", followed by the 'build' and 'install' actions in that directory. Use
PERL_MB_OPT or .modulebuildrc to set options that should be applied during
subprocesses

distmeta
[version 0.21]

Creates the META.yml file that describes the distribution.

META.yml is a file containing various bits of metadata about the distribution. The
metadata includes the distribution name, version, abstract, prerequisites, license,
and various other data about the distribution. This file is created as META.yml in a
simplified YAML format.

META.yml file must also be listed in MANIFEST - if it's not, a warning will be issued.

The current version of the META.yml specification can be found on CPAN as
CPAN::Meta::Spec.

distsign
[version 0.16]

Uses "Module::Signature" to create a SIGNATURE file for your distribution, and adds
the SIGNATURE file to the distribution's MANIFEST.

disttest
[version 0.05]

Performs the 'distdir' action, then switches into that directory and runs a "perl
Build.PL", followed by the 'build' and 'test' actions in that directory. Use
PERL_MB_OPT or .modulebuildrc to set options that should be applied during
subprocesses

docs
[version 0.20]

This will generate documentation (e.g. Unix man pages and HTML documents) for any
installable items under blib/ that contain POD. If there are no "bindoc" or "libdoc"
installation targets defined (as will be the case on systems that don't support Unix
manpages) no action is taken for manpages. If there are no "binhtml" or "libhtml"
installation targets defined no action is taken for HTML documents.

fakeinstall
[version 0.02]

This is just like the "install" action, but it won't actually do anything, it will
just report what it would have done if you had actually run the "install" action.

help
[version 0.03]

This action will simply print out a message that is meant to help you use the build
process. It will show you a list of available build actions too.

With an optional argument specifying an action name (e.g. "Build help test"), the
'help' action will show you any POD documentation it can find for that action.

html
[version 0.26]

This will generate HTML documentation for any binary or library files under blib/ that
contain POD. The HTML documentation will only be installed if the install paths can
be determined from values in "Config.pm". You can also supply or override install
paths on the command line by specifying "install_path" values for the "binhtml" and/or
"libhtml" installation targets.

install
[version 0.01]

This action will use "ExtUtils::Install" to install the files from "blib/" into the
system. See "INSTALL PATHS" for details about how Module::Build determines where to
install things, and how to influence this process.

If you want the installation process to look around in @INC for other versions of the
stuff you're installing and try to delete it, you can use the "uninst" parameter,
which tells "ExtUtils::Install" to do so:

./Build install uninst=1

This can be a good idea, as it helps prevent multiple versions of a module from being
present on your system, which can be a confusing situation indeed.

installdeps
[version 0.36]

This action will use the "cpan_client" parameter as a command to install missing
prerequisites. You will be prompted whether to install optional dependencies.

The "cpan_client" option defaults to 'cpan' but can be set as an option or in
.modulebuildrc. It must be a shell command that takes a list of modules to install as
arguments (e.g. 'cpanp -i' for CPANPLUS). If the program part is a relative path
(e.g. 'cpan' or 'cpanp'), it will be located relative to the perl program that
executed Build.PL.

/opt/perl/5.8.9/bin/perl Build.PL
./Build installdeps --cpan_client 'cpanp -i'
# installs to 5.8.9

manifest
[version 0.05]

This is an action intended for use by module authors, not people installing modules.
It will bring the MANIFEST up to date with the files currently present in the
distribution. You may use a MANIFEST.SKIP file to exclude certain files or
directories from inclusion in the MANIFEST. MANIFEST.SKIP should contain a bunch of
regular expressions, one per line. If a file in the distribution directory matches
any of the regular expressions, it won't be included in the MANIFEST.

The following is a reasonable MANIFEST.SKIP starting point, you can add your own stuff
to it:

^_build
^Build$
^blib
~$
\.bak$
^MANIFEST\.SKIP$
CVS

See the distcheck and skipcheck actions if you want to find out what the "manifest"
action would do, without actually doing anything.

manifest_skip
[version 0.3608]

This is an action intended for use by module authors, not people installing modules.
It will generate a boilerplate MANIFEST.SKIP file if one does not already exist.

manpages
[version 0.28]

This will generate man pages for any binary or library files under blib/ that contain
POD. The man pages will only be installed if the install paths can be determined from
values in "Config.pm". You can also supply or override install paths by specifying
there values on the command line with the "bindoc" and "libdoc" installation targets.

pardist
[version 0.2806]

Generates a PAR binary distribution for use with PAR or PAR::Dist.

It requires that the PAR::Dist module (version 0.17 and up) is installed on your
system.

ppd [version 0.20]

Build a PPD file for your distribution.

This action takes an optional argument "codebase" which is used in the generated PPD
file to specify the (usually relative) URL of the distribution. By default, this
value is the distribution name without any path information.

Example:

./Build ppd --codebase "MSWin32-x86-multi-thread/Module-Build-0.21.tar.gz"

ppmdist
[version 0.23]

Generates a PPM binary distribution and a PPD description file. This action also
invokes the "ppd" action, so it can accept the same "codebase" argument described
under that action.

This uses the same mechanism as the "dist" action to tar & zip its output, so you can
supply "tar" and/or "gzip" parameters to affect the result.

prereq_data
[version 0.32]

This action prints out a Perl data structure of all prerequisites and the versions
required. The output can be loaded again using "eval()". This can be useful for
external tools that wish to query a Build script for prerequisites.

prereq_report
[version 0.28]

This action prints out a list of all prerequisites, the versions required, and the
versions actually installed. This can be useful for reviewing the configuration of
your system prior to a build, or when compiling data to send for a bug report.

pure_install
[version 0.28]

This action is identical to the "install" action. In the future, though, when
"install" starts writing to the file $(INSTALLARCHLIB)/perllocal.pod, "pure_install"
won't, and that will be the only difference between them.

realclean
[version 0.01]

This action is just like the "clean" action, but also removes the "_build" directory
and the "Build" script. If you run the "realclean" action, you are essentially
starting over, so you will have to re-create the "Build" script again.

retest
[version 0.2806]

This is just like the "test" action, but doesn't actually build the distribution
first, and doesn't add blib/ to the load path, and therefore will test against a
previously installed version of the distribution. This can be used to verify that a
certain installed distribution still works, or to see whether newer versions of a
distribution still pass the old regression tests, and so on.

skipcheck
[version 0.05]

Reports which files are skipped due to the entries in the MANIFEST.SKIP file (See
manifest for details)

test
[version 0.01]

This will use "Test::Harness" or "TAP::Harness" to run any regression tests and report
their results. Tests can be defined in the standard places: a file called "test.pl" in
the top-level directory, or several files ending with ".t" in a "t/" directory.

If you want tests to be 'verbose', i.e. show details of test execution rather than
just summary information, pass the argument "verbose=1".

If you want to run tests under the perl debugger, pass the argument "debugger=1".

If you want to have Module::Build find test files with different file name extensions,
pass the "test_file_exts" argument with an array of extensions, such as "[qw( .t .s .z
)]".

If you want test to be run by "TAP::Harness", rather than "Test::Harness", pass the
argument "tap_harness_args" as an array reference of arguments to pass to the
TAP::Harness constructor.

In addition, if a file called "visual.pl" exists in the top-level directory, this file
will be executed as a Perl script and its output will be shown to the user. This is a
good place to put speed tests or other tests that don't use the "Test::Harness" format
for output.

To override the choice of tests to run, you may pass a "test_files" argument whose
value is a whitespace-separated list of test scripts to run. This is especially
useful in development, when you only want to run a single test to see whether you've
squashed a certain bug yet:

./Build test --test_files t/something_failing.t

You may also pass several "test_files" arguments separately:

./Build test --test_files t/one.t --test_files t/two.t

or use a "glob()"-style pattern:

./Build test --test_files 't/01-*.t'

testall
[version 0.2807]

[Note: the 'testall' action and the code snippets below are currently in alpha stage,
see "/www.nntp.perl.org/group/perl.module.build/2007/03/msg584.html"" in "http: ]

Runs the "test" action plus each of the "test$type" actions defined by the keys of the
"test_types" parameter.

Currently, you need to define the ACTION_test$type method yourself and enumerate them
in the test_types parameter.

my $mb = Module::Build->subclass(
code => q(
sub ACTION_testspecial { shift->generic_test(type => 'special'); }
sub ACTION_testauthor { shift->generic_test(type => 'author'); }
)
)->new(
...
test_types => {
special => '.st',
author => ['.at', '.pt' ],
},
...

testcover
[version 0.26]

Runs the "test" action using "Devel::Cover", generating a code-coverage report showing
which parts of the code were actually exercised during the tests.

To pass options to "Devel::Cover", set the $DEVEL_COVER_OPTIONS environment variable:

DEVEL_COVER_OPTIONS=-ignore,Build ./Build testcover

testdb
[version 0.05]

This is a synonym for the 'test' action with the "debugger=1" argument.

testpod
[version 0.25]

This checks all the files described in the "docs" action and produces
"Test::Harness"-style output. If you are a module author, this is useful to run
before creating a new release.

testpodcoverage
[version 0.28]

This checks the pod coverage of the distribution and produces "Test::Harness"-style
output. If you are a module author, this is useful to run before creating a new
release.

versioninstall
[version 0.16]

** Note: since "only.pm" is so new, and since we just recently added support for it
here too, this feature is to be considered experimental. **

If you have the "only.pm" module installed on your system, you can use this action to
install a module into the version-specific library trees. This means that you can
have several versions of the same module installed and "use" a specific one like this:

use only MyModule => 0.55;

To override the default installation libraries in "only::config", specify the
"versionlib" parameter when you run the "Build.PL" script:

perl Build.PL --versionlib /my/version/place/

To override which version the module is installed as, specify the "version" parameter
when you run the "Build.PL" script:

perl Build.PL --version 0.50

See the "only.pm" documentation for more information on version-specific installs.

OPTIONS

Command Line Options
The following options can be used during any invocation of "Build.PL" or the Build script,
during any action. For information on other options specific to an action, see the
documentation for the respective action.

NOTE: There is some preliminary support for options to use the more familiar long option
style. Most options can be preceded with the "--" long option prefix, and the underscores
changed to dashes (e.g. "--use-rcfile"). Additionally, the argument to boolean options is
optional, and boolean options can be negated by prefixing them with "no" or "no-" (e.g.
"--noverbose" or "--no-verbose").

quiet
Suppress informative messages on output.

verbose
Display extra information about the Build on output. "verbose" will turn off "quiet"

cpan_client
Sets the "cpan_client" command for use with the "installdeps" action. See
"installdeps" for more details.

use_rcfile
Load the ~/.modulebuildrc option file. This option can be set to false to prevent the
custom resource file from being loaded.

allow_mb_mismatch
Suppresses the check upon startup that the version of Module::Build we're now running
under is the same version that was initially invoked when building the distribution
(i.e. when the "Build.PL" script was first run). As of 0.3601, a mismatch results in
a warning instead of a fatal error, so this option effectively just suppresses the
warning.

debug
Prints Module::Build debugging information to STDOUT, such as a trace of executed
build actions.

Default Options File (.modulebuildrc)
[version 0.28]

When Module::Build starts up, it will look first for a file, $ENV{HOME}/.modulebuildrc.
If it's not found there, it will look in the the .modulebuildrc file in the directories
referred to by the environment variables "HOMEDRIVE" + "HOMEDIR", "USERPROFILE",
"APPDATA", "WINDIR", "SYS$LOGIN". If the file exists, the options specified there will be
used as defaults, as if they were typed on the command line. The defaults can be
overridden by specifying new values on the command line.

The action name must come at the beginning of the line, followed by any amount of
whitespace and then the options. Options are given the same as they would be on the
command line. They can be separated by any amount of whitespace, including newlines, as
long there is whitespace at the beginning of each continued line. Anything following a
hash mark ("#") is considered a comment, and is stripped before parsing. If more than one
line begins with the same action name, those lines are merged into one set of options.

Besides the regular actions, there are two special pseudo-actions: the key "*" (asterisk)
denotes any global options that should be applied to all actions, and the key 'Build_PL'
specifies options to be applied when you invoke "perl Build.PL".

* verbose=1 # global options
diff flags=-u
install --install_base /home/ken
--install_path html=/home/ken/docs/html
installdeps --cpan_client 'cpanp -i'

If you wish to locate your resource file in a different location, you can set the
environment variable "MODULEBUILDRC" to the complete absolute path of the file containing
your options.

Environment variables
MODULEBUILDRC
[version 0.28]

Specifies an alternate location for a default options file as described above.

PERL_MB_OPT
[version 0.36]

Command line options that are applied to Build.PL or any Build action. The string is
split as the shell would (e.g. whitespace) and the result is prepended to any actual
command-line arguments.

INSTALL PATHS

[version 0.19]

When you invoke Module::Build's "build" action, it needs to figure out where to install
things. The nutshell version of how this works is that default installation locations are
determined from Config.pm, and they may be overridden by using the "install_path"
parameter. An "install_base" parameter lets you specify an alternative installation root
like /home/foo, and a "destdir" lets you specify a temporary installation directory like
/tmp/install in case you want to create bundled-up installable packages.

Natively, Module::Build provides default installation locations for the following types of
installable items:

lib Usually pure-Perl module files ending in .pm.

arch
"Architecture-dependent" module files, usually produced by compiling XS, Inline, or
similar code.

script
Programs written in pure Perl. In order to improve reuse, try to make these as small
as possible - put the code into modules whenever possible.

bin "Architecture-dependent" executable programs, i.e. compiled C code or something.
Pretty rare to see this in a perl distribution, but it happens.

bindoc
Documentation for the stuff in "script" and "bin". Usually generated from the POD in
those files. Under Unix, these are manual pages belonging to the 'man1' category.

libdoc
Documentation for the stuff in "lib" and "arch". This is usually generated from the
POD in .pm files. Under Unix, these are manual pages belonging to the 'man3'
category.

binhtml
This is the same as "bindoc" above, but applies to HTML documents.

libhtml
This is the same as "libdoc" above, but applies to HTML documents.

Four other parameters let you control various aspects of how installation paths are
determined:

installdirs
The default destinations for these installable things come from entries in your
system's "Config.pm". You can select from three different sets of default locations
by setting the "installdirs" parameter as follows:

'installdirs' set to:
core site vendor

uses the following defaults from Config.pm:

lib => installprivlib installsitelib installvendorlib
arch => installarchlib installsitearch installvendorarch
script => installscript installsitescript installvendorscript
bin => installbin installsitebin installvendorbin
bindoc => installman1dir installsiteman1dir installvendorman1dir
libdoc => installman3dir installsiteman3dir installvendorman3dir
binhtml => installhtml1dir installsitehtml1dir installvendorhtml1dir [*]
libhtml => installhtml3dir installsitehtml3dir installvendorhtml3dir [*]

* Under some OS (eg. MSWin32) the destination for HTML documents is
determined by the C<Config.pm> entry C<installhtmldir>.

The default value of "installdirs" is "site". If you're creating vendor distributions
of module packages, you may want to do something like this:

perl Build.PL --installdirs vendor

./Build install --installdirs vendor

If you're installing an updated version of a module that was included with perl itself
(i.e. a "core module"), then you may set "installdirs" to "core" to overwrite the
module in its present location.

(Note that the 'script' line is different from "MakeMaker" - unfortunately there's no
such thing as "installsitescript" or "installvendorscript" entry in "Config.pm", so we
use the "installsitebin" and "installvendorbin" entries to at least get the general
location right. In the future, if "Config.pm" adds some more appropriate entries,
we'll start using those.)

install_path
Once the defaults have been set, you can override them.

On the command line, that would look like this:

perl Build.PL --install_path lib=/foo/lib --install_path arch=/foo/lib/arch

or this:

./Build install --install_path lib=/foo/lib --install_path arch=/foo/lib/arch

install_base
You can also set the whole bunch of installation paths by supplying the "install_base"
parameter to point to a directory on your system. For instance, if you set
"install_base" to "/home/ken" on a Linux system, you'll install as follows:

lib => /home/ken/lib/perl5
arch => /home/ken/lib/perl5/i386-linux
script => /home/ken/bin
bin => /home/ken/bin
bindoc => /home/ken/man/man1
libdoc => /home/ken/man/man3
binhtml => /home/ken/html
libhtml => /home/ken/html

Note that this is different from how "MakeMaker"'s "PREFIX" parameter works.
"install_base" just gives you a default layout under the directory you specify, which
may have little to do with the "installdirs=site" layout.

The exact layout under the directory you specify may vary by system - we try to do the
"sensible" thing on each platform.

destdir
If you want to install everything into a temporary directory first (for instance, if
you want to create a directory tree that a package manager like "rpm" or "dpkg" could
create a package from), you can use the "destdir" parameter:

perl Build.PL --destdir /tmp/foo

./Build install --destdir /tmp/foo

This will effectively install to "/tmp/foo/$sitelib", "/tmp/foo/$sitearch", and the
like, except that it will use "File::Spec" to make the pathnames work correctly on
whatever platform you're installing on.

prefix
Provided for compatibility with "ExtUtils::MakeMaker"'s PREFIX argument. "prefix"
should be used when you want Module::Build to install your modules, documentation, and
scripts in the same place as "ExtUtils::MakeMaker"'s PREFIX mechanism.

The following are equivalent.

perl Build.PL --prefix /tmp/foo
perl Makefile.PL PREFIX=/tmp/foo

Because of the complex nature of the prefixification logic, the behavior of PREFIX in
"MakeMaker" has changed subtly over time. Module::Build's --prefix logic is
equivalent to the PREFIX logic found in "ExtUtils::MakeMaker" 6.30.

The maintainers of "MakeMaker" do understand the troubles with the PREFIX mechanism,
and added INSTALL_BASE support in version 6.31 of "MakeMaker", which was released in
2006.

If you don't need to retain compatibility with old versions (pre-6.31) of
"ExtUtils::MakeMaker" or are starting a fresh Perl installation we recommend you use
"install_base" instead (and "INSTALL_BASE" in "ExtUtils::MakeMaker"). See "Installing
in the same location as ExtUtils::MakeMaker" in Module::Build::Cookbook for further
information.

MOTIVATIONS

       There are several reasons I wanted to start over, and not just fix what I didn't like
       about "MakeMaker":

       •   I don't like the core idea of "MakeMaker", namely that "make" should be involved in
           the build process.  Here are my reasons:

           +   When a person is installing a Perl module, what can you assume about their
               environment?  Can you assume they have "make"?  No, but you can assume they have
               some version of Perl.

           +   When a person is writing a Perl module for intended distribution, can you assume
               that they know how to build a Makefile, so they can customize their build process?
               No, but you can assume they know Perl, and could customize that way.

           For years, these things have been a barrier to people getting the build/install
           process to do what they want.

       •   There are several architectural decisions in "MakeMaker" that make it very difficult
           to customize its behavior.  For instance, when using "MakeMaker" you do "use
           ExtUtils::MakeMaker", but the object created in "WriteMakefile()" is actually blessed
           into a package name that's created on the fly, so you can't simply subclass
           "ExtUtils::MakeMaker".  There is a workaround "MY" package that lets you override
           certain "MakeMaker" methods, but only certain explicitly preselected (by "MakeMaker")
           methods can be overridden.  Also, the method of customization is very crude: you have
           to modify a string containing the Makefile text for the particular target.  Since
           these strings aren't documented, and can't be documented (they take on different
           values depending on the platform, version of perl, version of "MakeMaker", etc.), you
           have no guarantee that your modifications will work on someone else's machine or after
           an upgrade of "MakeMaker" or perl.

       •   It is risky to make major changes to "MakeMaker", since it does so many things, is so
           important, and generally works.  "Module::Build" is an entirely separate package so
           that I can work on it all I want, without worrying about backward compatibility with
           "MakeMaker".

       •   Finally, Perl is said to be a language for system administration.  Could it really be
           the case that Perl isn't up to the task of building and installing software?  Even if
           that software is a bunch of ".pm" files that just need to be copied from one place to
           another?  My sense was that we could design a system to accomplish this in a flexible,
           extensible, and friendly manner.  Or die trying.

TO DO

       The current method of relying on time stamps to determine whether a derived file is out of
       date isn't likely to scale well, since it requires tracing all dependencies backward, it
       runs into problems on NFS, and it's just generally flimsy.  It would be better to use an
       MD5 signature or the like, if available.  See "cons" for an example.

        - append to perllocal.pod
        - add a 'plugin' functionality

AUTHOR

       Ken Williams <kwilliams@cpan.org>

       Development questions, bug reports, and patches should be sent to the Module-Build mailing
       list at <module-build@perl.org>.

       Bug reports are also welcome at <http://rt.cpan.org/NoAuth/Bugs.html?Dist=Module-Build>.

       The latest development version is available from the Git repository at
       <https://github.com/Perl-Toolchain-Gang/Module-Build>

COPYRIGHT

       Copyright (c) 2001-2006 Ken Williams.  All rights reserved.

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