3 # This module doesn't do much of anything itself, it inherits from the
4 # modules that do the real work. The only real thing it has to do is
5 # figure out which OS-specific module to pull in. Many of the
6 # OS-specific modules don't do anything either - most of the work is
7 # done in Module::Build::Base.
12 use File::Basename ();
14 use Module::Build::Base;
16 use vars qw($VERSION @ISA);
17 @ISA = qw(Module::Build::Base);
19 $VERSION = eval $VERSION;
21 # Okay, this is the brute-force method of finding out what kind of
22 # platform we're on. I don't know of a systematic way. These values
23 # came from the latest (bleadperl) perlport.pod.
73 # Inserts the given module into the @ISA hierarchy between
74 # Module::Build and its immediate parent
75 sub _interpose_module {
76 my ($self, $mod) = @_;
82 while (@{"${top_class}::ISA"}) {
83 last if ${"${top_class}::ISA"}[0] eq $ISA[0];
84 $top_class = ${"${top_class}::ISA"}[0];
87 @{"${top_class}::ISA"} = @ISA;
91 if (grep {-e File::Spec->catfile($_, qw(Module Build Platform), $^O) . '.pm'} @INC) {
92 __PACKAGE__->_interpose_module("Module::Build::Platform::$^O");
94 } elsif (exists $OSTYPES{$^O}) {
95 __PACKAGE__->_interpose_module("Module::Build::Platform::$OSTYPES{$^O}");
98 warn "Unknown OS type '$^O' - using default settings\n";
101 sub os_type { $OSTYPES{$^O} }
103 sub is_vmsish { return ((os_type() || '') eq 'VMS') }
104 sub is_windowsish { return ((os_type() || '') eq 'Windows') }
105 sub is_unixish { return ((os_type() || '') eq 'Unix') }
114 Module::Build - Build and install Perl modules
119 Standard process for building & installing modules:
126 Or, if you're on a platform (like DOS or Windows) that doesn't require
127 the "./" notation, you can do this:
137 C<Module::Build> is a system for building, testing, and installing
138 Perl modules. It is meant to be an alternative to
139 C<ExtUtils::MakeMaker>. Developers may alter the behavior of the
140 module through subclassing in a much more straightforward way than
141 with C<MakeMaker>. It also does not require a C<make> on your system
142 - most of the C<Module::Build> code is pure-perl and written in a very
143 cross-platform way. In fact, you don't even need a shell, so even
144 platforms like MacOS (traditional) can use it fairly easily. Its only
145 prerequisites are modules that are included with perl 5.6.0, and it
146 works fine on perl 5.005 if you can install a few additional modules.
148 See L<"MOTIVATIONS"> for more comparisons between C<ExtUtils::MakeMaker>
149 and C<Module::Build>.
151 To install C<Module::Build>, and any other module that uses
152 C<Module::Build> for its installation process, do the following:
154 perl Build.PL # 'Build.PL' script creates the 'Build' script
155 ./Build # Need ./ to ensure we're using this "Build" script
156 ./Build test # and not another one that happens to be in the PATH
159 This illustrates initial configuration and the running of three
160 'actions'. In this case the actions run are 'build' (the default
161 action), 'test', and 'install'. Other actions defined so far include:
169 distcheck pure_install
179 install versioninstall
182 You can run the 'help' action for a complete list of actions.
185 =head1 GUIDE TO DOCUMENTATION
187 The documentation for C<Module::Build> is broken up into three sections:
191 =item General Usage (L<Module::Build>)
193 This is the document you are currently reading. It describes basic
194 usage and background information. Its main purpose is to assist the
195 user who wants to learn how to invoke and control C<Module::Build>
196 scripts at the command line.
198 =item Authoring Reference (L<Module::Build::Authoring>)
200 This document describes the structure and organization of
201 C<Module::Build>, and the relevant concepts needed by authors who are
202 writing F<Build.PL> scripts for a distribution or controlling
203 C<Module::Build> processes programmatically.
205 =item API Reference (L<Module::Build::API>)
207 This is a reference to the C<Module::Build> API.
209 =item Cookbook (L<Module::Build::Cookbook>)
211 This document demonstrates how to accomplish many common tasks. It
212 covers general command line usage and authoring of F<Build.PL>
213 scripts. Includes working examples.
220 There are some general principles at work here. First, each task when
221 building a module is called an "action". These actions are listed
222 above; they correspond to the building, testing, installing,
223 packaging, etc., tasks.
225 Second, arguments are processed in a very systematic way. Arguments
226 are always key=value pairs. They may be specified at C<perl Build.PL>
227 time (i.e. C<perl Build.PL destdir=/my/secret/place>), in which case
228 their values last for the lifetime of the C<Build> script. They may
229 also be specified when executing a particular action (i.e.
230 C<Build test verbose=1>), in which case their values last only for the
231 lifetime of that command. Per-action command line parameters take
232 precedence over parameters specified at C<perl Build.PL> time.
234 The build process also relies heavily on the C<Config.pm> module.
235 If the user wishes to override any of the
236 values in C<Config.pm>, she may specify them like so:
238 perl Build.PL --config cc=gcc --config ld=gcc
240 The following build actions are provided by default.
248 If you run the C<Build> script without any arguments, it runs the
249 C<build> action, which in turn runs the C<code> and C<docs> actions.
251 This is analogous to the MakeMaker 'make all' target.
257 This action will clean up any files that the build process may have
258 created, including the C<blib/> directory (but not including the
259 C<_build/> directory and the C<Build> script itself).
265 This action builds your codebase.
267 By default it just creates a C<blib/> directory and copies any C<.pm>
268 and C<.pod> files from your C<lib/> directory into the C<blib/>
269 directory. It also compiles any C<.xs> files from C<lib/> and places
270 them in C<blib/>. Of course, you need a working C compiler (probably
271 the same one that built perl itself) for the compilation to work
274 The C<code> action also runs any C<.PL> files in your F<lib/>
275 directory. Typically these create other files, named the same but
276 without the C<.PL> ending. For example, a file F<lib/Foo/Bar.pm.PL>
277 could create the file F<lib/Foo/Bar.pm>. The C<.PL> files are
278 processed first, so any C<.pm> files (or other kinds that we deal
279 with) will get copied correctly.
291 This action will compare the files about to be installed with their
292 installed counterparts. For .pm and .pod files, a diff will be shown
293 (this currently requires a 'diff' program to be in your PATH). For
294 other files like compiled binary files, we simply report whether they
297 A C<flags> parameter may be passed to the action, which will be passed
298 to the 'diff' program. Consult your 'diff' documentation for the
299 parameters it will accept - a good one is C<-u>:
301 ./Build diff flags=-u
307 This action is helpful for module authors who want to package up their
308 module for source distribution through a medium like CPAN. It will create a
309 tarball of the files listed in F<MANIFEST> and compress the tarball using
312 By default, this action will use the external C<tar> and C<gzip>
313 executables on Unix-like platforms, and the C<Archive::Tar> module
314 elsewhere. However, you can force it to use whatever executable you
315 want by supplying an explicit C<tar> (and optional C<gzip>) parameter:
317 ./Build dist --tar C:\path\to\tar.exe --gzip C:\path\to\zip.exe
323 Reports which files are in the build directory but not in the
324 F<MANIFEST> file, and vice versa. (See L<manifest> for details.)
330 Performs the 'realclean' action and then the 'distcheck' action.
336 Creates a "distribution directory" named C<$dist_name-$dist_version>
337 (if that directory already exists, it will be removed first), then
338 copies all the files listed in the F<MANIFEST> file to that directory.
339 This directory is what the distribution tarball is created from.
345 Creates the F<META.yml> file that describes the distribution.
347 F<META.yml> is a file containing various bits of "metadata" about the
348 distribution. The metadata includes the distribution name, version,
349 abstract, prerequisites, license, and various other data about the
350 distribution. This file is created as F<META.yml> in YAML format.
351 It is recommended that the C<YAML> module be installed to create it.
352 If the C<YAML> module is not installed, an internal module supplied
353 with Module::Build will be used to write the META.yml file, and this
354 will most likely be fine.
356 F<META.yml> file must also be listed in F<MANIFEST> - if it's not, a
357 warning will be issued.
359 The current version of the F<META.yml> specification can be found at
360 L<http://module-build.sourceforge.net/META-spec-current.html>
366 Uses C<Module::Signature> to create a SIGNATURE file for your
367 distribution, and adds the SIGNATURE file to the distribution's
374 Performs the 'distdir' action, then switches into that directory and
375 runs a C<perl Build.PL>, followed by the 'build' and 'test' actions in
382 This will generate documentation (e.g. Unix man pages and html
383 documents) for any installable items under B<blib/> that
384 contain POD. If there are no C<bindoc> or C<libdoc> installation
385 targets defined (as will be the case on systems that don't support
386 Unix manpages) no action is taken for manpages. If there are no
387 C<binhtml> or C<libhtml> installation targets defined no action is
388 taken for html documents.
394 This is just like the C<install> action, but it won't actually do
395 anything, it will just report what it I<would> have done if you had
396 actually run the C<install> action.
402 This action will simply print out a message that is meant to help you
403 use the build process. It will show you a list of available build
406 With an optional argument specifying an action name (e.g. C<Build help
407 test>), the 'help' action will show you any POD documentation it can
408 find for that action.
414 This will generate HTML documentation for any binary or library files
415 under B<blib/> that contain POD. The HTML documentation will only be
416 installed if the install paths can be determined from values in
417 C<Config.pm>. You can also supply or override install paths on the
418 command line by specifying C<install_path> values for the C<binhtml>
419 and/or C<libhtml> installation targets.
425 This action will use C<ExtUtils::Install> to install the files from
426 C<blib/> into the system. See L<"INSTALL PATHS">
427 for details about how Module::Build determines where to install
428 things, and how to influence this process.
430 If you want the installation process to look around in C<@INC> for
431 other versions of the stuff you're installing and try to delete it,
432 you can use the C<uninst> parameter, which tells C<ExtUtils::Install> to
435 ./Build install uninst=1
437 This can be a good idea, as it helps prevent multiple versions of a
438 module from being present on your system, which can be a confusing
445 This is an action intended for use by module authors, not people
446 installing modules. It will bring the F<MANIFEST> up to date with the
447 files currently present in the distribution. You may use a
448 F<MANIFEST.SKIP> file to exclude certain files or directories from
449 inclusion in the F<MANIFEST>. F<MANIFEST.SKIP> should contain a bunch
450 of regular expressions, one per line. If a file in the distribution
451 directory matches any of the regular expressions, it won't be included
454 The following is a reasonable F<MANIFEST.SKIP> starting point, you can
455 add your own stuff to it:
465 See the L<distcheck> and L<skipcheck> actions if you want to find out
466 what the C<manifest> action would do, without actually doing anything.
472 This will generate man pages for any binary or library files under
473 B<blib/> that contain POD. The man pages will only be installed if the
474 install paths can be determined from values in C<Config.pm>. You can
475 also supply or override install paths by specifying there values on
476 the command line with the C<bindoc> and C<libdoc> installation
483 Generates a PAR binary distribution for use with L<PAR> or L<PAR::Dist>.
485 It requires that the PAR::Dist module (version 0.17 and up) is
486 installed on your system.
492 Build a PPD file for your distribution.
494 This action takes an optional argument C<codebase> which is used in
495 the generated ppd file to specify the (usually relative) URL of the
496 distribution. By default, this value is the distribution name without
497 any path information.
501 ./Build ppd --codebase "MSWin32-x86-multi-thread/Module-Build-0.21.tar.gz"
507 Generates a PPM binary distribution and a PPD description file. This
508 action also invokes the 'ppd' action, so it can accept the same
509 C<codebase> argument described under that action.
511 This uses the same mechanism as the C<dist> action to tar & zip its
512 output, so you can supply C<tar> and/or C<gzip> parameters to affect
519 This action prints out a list of all prerequisites, the versions required, and
520 the versions actually installed. This can be useful for reviewing the
521 configuration of your system prior to a build, or when compiling data to send
528 This action is identical to the C<install> action. In the future,
529 though, when C<install> starts writing to the file
530 F<$(INSTALLARCHLIB)/perllocal.pod>, C<pure_install> won't, and that
531 will be the only difference between them.
537 This action is just like the C<clean> action, but also removes the
538 C<_build> directory and the C<Build> script. If you run the
539 C<realclean> action, you are essentially starting over, so you will
540 have to re-create the C<Build> script again.
546 This is just like the C<test> action, but doesn't actually build the
547 distribution first, and doesn't add F<blib/> to the load path, and
548 therefore will test against a I<previously> installed version of the
549 distribution. This can be used to verify that a certain installed
550 distribution still works, or to see whether newer versions of a
551 distribution still pass the old regression tests, and so on.
557 Reports which files are skipped due to the entries in the
558 F<MANIFEST.SKIP> file (See L<manifest> for details)
564 This will use C<Test::Harness> or C<TAP::Harness> to run any regression
565 tests and report their results. Tests can be defined in the standard
566 places: a file called C<test.pl> in the top-level directory, or several
567 files ending with C<.t> in a C<t/> directory.
569 If you want tests to be 'verbose', i.e. show details of test execution
570 rather than just summary information, pass the argument C<verbose=1>.
572 If you want to run tests under the perl debugger, pass the argument
575 If you want to have Module::Build find test files with different file
576 name extensions, pass the C<test_file_exts> argument with an array
577 of extensions, such as C<[qw( .t .s .z )]>.
579 If you want test to be run by C<TAP::Harness>, rather than C<Test::Harness>,
580 pass the argument C<tap_harness_args> as an array reference of arguments to
581 pass to the TAP::Harness constructor.
583 In addition, if a file called C<visual.pl> exists in the top-level
584 directory, this file will be executed as a Perl script and its output
585 will be shown to the user. This is a good place to put speed tests or
586 other tests that don't use the C<Test::Harness> format for output.
588 To override the choice of tests to run, you may pass a C<test_files>
589 argument whose value is a whitespace-separated list of test scripts to
590 run. This is especially useful in development, when you only want to
591 run a single test to see whether you've squashed a certain bug yet:
593 ./Build test --test_files t/something_failing.t
595 You may also pass several C<test_files> arguments separately:
597 ./Build test --test_files t/one.t --test_files t/two.t
599 or use a C<glob()>-style pattern:
601 ./Build test --test_files 't/01-*.t'
607 [Note: the 'testall' action and the code snippets below are currently
609 L<"http://www.nntp.perl.org/group/perl.module.build/2007/03/msg584.html"> ]
611 Runs the C<test> action plus each of the C<test$type> actions defined by
612 the keys of the C<test_types> parameter.
614 Currently, you need to define the ACTION_test$type method yourself and
615 enumerate them in the test_types parameter.
617 my $mb = Module::Build->subclass(
619 sub ACTION_testspecial { shift->generic_test(type => 'special'); }
620 sub ACTION_testauthor { shift->generic_test(type => 'author'); }
626 author => ['.at', '.pt' ],
634 Runs the C<test> action using C<Devel::Cover>, generating a
635 code-coverage report showing which parts of the code were actually
636 exercised during the tests.
638 To pass options to C<Devel::Cover>, set the C<$DEVEL_COVER_OPTIONS>
639 environment variable:
641 DEVEL_COVER_OPTIONS=-ignore,Build ./Build testcover
647 This is a synonym for the 'test' action with the C<debugger=1>
654 This checks all the files described in the C<docs> action and
655 produces C<Test::Harness>-style output. If you are a module author,
656 this is useful to run before creating a new release.
658 =item testpodcoverage
662 This checks the pod coverage of the distribution and
663 produces C<Test::Harness>-style output. If you are a module author,
664 this is useful to run before creating a new release.
670 ** Note: since C<only.pm> is so new, and since we just recently added
671 support for it here too, this feature is to be considered
674 If you have the C<only.pm> module installed on your system, you can
675 use this action to install a module into the version-specific library
676 trees. This means that you can have several versions of the same
677 module installed and C<use> a specific one like this:
679 use only MyModule => 0.55;
681 To override the default installation libraries in C<only::config>,
682 specify the C<versionlib> parameter when you run the C<Build.PL> script:
684 perl Build.PL --versionlib /my/version/place/
686 To override which version the module is installed as, specify the
687 C<versionlib> parameter when you run the C<Build.PL> script:
689 perl Build.PL --version 0.50
691 See the C<only.pm> documentation for more information on
692 version-specific installs.
699 =head2 Command Line Options
701 The following options can be used during any invocation of C<Build.PL>
702 or the Build script, during any action. For information on other
703 options specific to an action, see the documentation for the
706 NOTE: There is some preliminary support for options to use the more
707 familiar long option style. Most options can be preceded with the
708 C<--> long option prefix, and the underscores changed to dashes
709 (e.g. --use-rcfile). Additionally, the argument to boolean options is
710 optional, and boolean options can be negated by prefixing them with
711 'no' or 'no-' (e.g. --noverbose or --no-verbose).
717 Suppress informative messages on output.
721 Load the F<~/.modulebuildrc> option file. This option can be set to
722 false to prevent the custom resource file from being loaded.
726 Display extra information about the Build on output.
728 =item allow_mb_mismatch
730 Suppresses the check upon startup that the version of Module::Build
731 we're now running under is the same version that was initially invoked
732 when building the distribution (i.e. when the C<Build.PL> script was
733 first run). Use with caution.
738 =head2 Default Options File (F<.modulebuildrc>)
742 When Module::Build starts up, it will look first for a file,
743 F<$ENV{HOME}/.modulebuildrc>. If it's not found there, it will look
744 in the the F<.modulebuildrc> file in the directories referred to by
745 the environment variables C<HOMEDRIVE> + C<HOMEDIR>, C<USERPROFILE>,
746 C<APPDATA>, C<WINDIR>, C<SYS$LOGIN>. If the file exists, the options
747 specified there will be used as defaults, as if they were typed on the
748 command line. The defaults can be overridden by specifying new values
751 The action name must come at the beginning of the line, followed by any
752 amount of whitespace and then the options. Options are given the same
753 as they would be on the command line. They can be separated by any
754 amount of whitespace, including newlines, as long there is whitespace at
755 the beginning of each continued line. Anything following a hash mark (C<#>)
756 is considered a comment, and is stripped before parsing. If more than
757 one line begins with the same action name, those lines are merged into
760 Besides the regular actions, there are two special pseudo-actions: the
761 key C<*> (asterisk) denotes any global options that should be applied
762 to all actions, and the key 'Build_PL' specifies options to be applied
763 when you invoke C<perl Build.PL>.
765 * verbose=1 # global options
767 install --install_base /home/ken
768 --install_path html=/home/ken/docs/html
770 If you wish to locate your resource file in a different location, you
771 can set the environment variable 'MODULEBUILDRC' to the complete
772 absolute path of the file containing your options.
779 When you invoke Module::Build's C<build> action, it needs to figure
780 out where to install things. The nutshell version of how this works
781 is that default installation locations are determined from
782 F<Config.pm>, and they may be overridden by using the C<install_path>
783 parameter. An C<install_base> parameter lets you specify an
784 alternative installation root like F</home/foo>, and a C<destdir> lets
785 you specify a temporary installation directory like F</tmp/install> in
786 case you want to create bundled-up installable packages.
788 Natively, Module::Build provides default installation locations for
789 the following types of installable items:
795 Usually pure-Perl module files ending in F<.pm>.
799 "Architecture-dependent" module files, usually produced by compiling
800 XS, Inline, or similar code.
804 Programs written in pure Perl. In order to improve reuse, try to make
805 these as small as possible - put the code into modules whenever
810 "Architecture-dependent" executable programs, i.e. compiled C code or
811 something. Pretty rare to see this in a perl distribution, but it
816 Documentation for the stuff in C<script> and C<bin>. Usually
817 generated from the POD in those files. Under Unix, these are manual
818 pages belonging to the 'man1' category.
822 Documentation for the stuff in C<lib> and C<arch>. This is usually
823 generated from the POD in F<.pm> files. Under Unix, these are manual
824 pages belonging to the 'man3' category.
828 This is the same as C<bindoc> above, but applies to html documents.
832 This is the same as C<bindoc> above, but applies to html documents.
836 Four other parameters let you control various aspects of how
837 installation paths are determined:
843 The default destinations for these installable things come from
844 entries in your system's C<Config.pm>. You can select from three
845 different sets of default locations by setting the C<installdirs>
846 parameter as follows:
848 'installdirs' set to:
851 uses the following defaults from Config.pm:
853 lib => installprivlib installsitelib installvendorlib
854 arch => installarchlib installsitearch installvendorarch
855 script => installscript installsitebin installvendorbin
856 bin => installbin installsitebin installvendorbin
857 bindoc => installman1dir installsiteman1dir installvendorman1dir
858 libdoc => installman3dir installsiteman3dir installvendorman3dir
859 binhtml => installhtml1dir installsitehtml1dir installvendorhtml1dir [*]
860 libhtml => installhtml3dir installsitehtml3dir installvendorhtml3dir [*]
862 * Under some OS (eg. MSWin32) the destination for html documents is
863 determined by the C<Config.pm> entry C<installhtmldir>.
865 The default value of C<installdirs> is "site". If you're creating
866 vendor distributions of module packages, you may want to do something
869 perl Build.PL --installdirs vendor
873 ./Build install --installdirs vendor
875 If you're installing an updated version of a module that was included
876 with perl itself (i.e. a "core module"), then you may set
877 C<installdirs> to "core" to overwrite the module in its present
880 (Note that the 'script' line is different from MakeMaker -
881 unfortunately there's no such thing as "installsitescript" or
882 "installvendorscript" entry in C<Config.pm>, so we use the
883 "installsitebin" and "installvendorbin" entries to at least get the
884 general location right. In the future, if C<Config.pm> adds some more
885 appropriate entries, we'll start using those.)
889 Once the defaults have been set, you can override them.
891 On the command line, that would look like this:
893 perl Build.PL --install_path lib=/foo/lib --install_path arch=/foo/lib/arch
897 ./Build install --install_path lib=/foo/lib --install_path arch=/foo/lib/arch
901 You can also set the whole bunch of installation paths by supplying the
902 C<install_base> parameter to point to a directory on your system. For
903 instance, if you set C<install_base> to "/home/ken" on a Linux
904 system, you'll install as follows:
906 lib => /home/ken/lib/perl5
907 arch => /home/ken/lib/perl5/i386-linux
908 script => /home/ken/bin
910 bindoc => /home/ken/man/man1
911 libdoc => /home/ken/man/man3
912 binhtml => /home/ken/html
913 libhtml => /home/ken/html
915 Note that this is I<different> from how MakeMaker's C<PREFIX>
916 parameter works. C<install_base> just gives you a default layout under the
917 directory you specify, which may have little to do with the
918 C<installdirs=site> layout.
920 The exact layout under the directory you specify may vary by system -
921 we try to do the "sensible" thing on each platform.
925 If you want to install everything into a temporary directory first
926 (for instance, if you want to create a directory tree that a package
927 manager like C<rpm> or C<dpkg> could create a package from), you can
928 use the C<destdir> parameter:
930 perl Build.PL --destdir /tmp/foo
934 ./Build install --destdir /tmp/foo
936 This will effectively install to "/tmp/foo/$sitelib",
937 "/tmp/foo/$sitearch", and the like, except that it will use
938 C<File::Spec> to make the pathnames work correctly on whatever
939 platform you're installing on.
943 Provided for compatibility with ExtUtils::MakeMaker's PREFIX argument.
944 C<prefix> should be used when you wish Module::Build to install your
945 modules, documentation and scripts in the same place
946 ExtUtils::MakeMaker does.
948 The following are equivalent.
950 perl Build.PL --prefix /tmp/foo
951 perl Makefile.PL PREFIX=/tmp/foo
953 Because of the very complex nature of the prefixification logic, the
954 behavior of PREFIX in MakeMaker has changed subtly over time.
955 Module::Build's --prefix logic is equivalent to the PREFIX logic found
956 in ExtUtils::MakeMaker 6.30.
958 If you do not need to retain compatibility with ExtUtils::MakeMaker or
959 are starting a fresh Perl installation we recommand you use
960 C<install_base> instead (and C<INSTALL_BASE> in ExtUtils::MakeMaker).
961 See L<Module::Build::Cookbook/Instaling in the same location as
962 ExtUtils::MakeMaker> for further information.
970 There are several reasons I wanted to start over, and not just fix
971 what I didn't like about MakeMaker:
977 I don't like the core idea of MakeMaker, namely that C<make> should be
978 involved in the build process. Here are my reasons:
984 When a person is installing a Perl module, what can you assume about
985 their environment? Can you assume they have C<make>? No, but you can
986 assume they have some version of Perl.
990 When a person is writing a Perl module for intended distribution, can
991 you assume that they know how to build a Makefile, so they can
992 customize their build process? No, but you can assume they know Perl,
993 and could customize that way.
997 For years, these things have been a barrier to people getting the
998 build/install process to do what they want.
1002 There are several architectural decisions in MakeMaker that make it
1003 very difficult to customize its behavior. For instance, when using
1004 MakeMaker you do C<use ExtUtils::MakeMaker>, but the object created in
1005 C<WriteMakefile()> is actually blessed into a package name that's
1006 created on the fly, so you can't simply subclass
1007 C<ExtUtils::MakeMaker>. There is a workaround C<MY> package that lets
1008 you override certain MakeMaker methods, but only certain explicitly
1009 preselected (by MakeMaker) methods can be overridden. Also, the method
1010 of customization is very crude: you have to modify a string containing
1011 the Makefile text for the particular target. Since these strings
1012 aren't documented, and I<can't> be documented (they take on different
1013 values depending on the platform, version of perl, version of
1014 MakeMaker, etc.), you have no guarantee that your modifications will
1015 work on someone else's machine or after an upgrade of MakeMaker or
1020 It is risky to make major changes to MakeMaker, since it does so many
1021 things, is so important, and generally works. C<Module::Build> is an
1022 entirely separate package so that I can work on it all I want, without
1023 worrying about backward compatibility.
1027 Finally, Perl is said to be a language for system administration.
1028 Could it really be the case that Perl isn't up to the task of building
1029 and installing software? Even if that software is a bunch of stupid
1030 little C<.pm> files that just need to be copied from one place to
1031 another? My sense was that we could design a system to accomplish
1032 this in a flexible, extensible, and friendly manner. Or die trying.
1039 The current method of relying on time stamps to determine whether a
1040 derived file is out of date isn't likely to scale well, since it
1041 requires tracing all dependencies backward, it runs into problems on
1042 NFS, and it's just generally flimsy. It would be better to use an MD5
1043 signature or the like, if available. See C<cons> for an example.
1045 - append to perllocal.pod
1046 - add a 'plugin' functionality
1051 Ken Williams <kwilliams@cpan.org>
1053 Development questions, bug reports, and patches should be sent to the
1054 Module-Build mailing list at <module-build@perl.org>.
1056 Bug reports are also welcome at
1057 <http://rt.cpan.org/NoAuth/Bugs.html?Dist=Module-Build>.
1059 The latest development version is available from the Subversion
1060 repository at <https://svn.perl.org/modules/Module-Build/trunk/>
1065 Copyright (c) 2001-2006 Ken Williams. All rights reserved.
1067 This library is free software; you can redistribute it and/or
1068 modify it under the same terms as Perl itself.
1073 perl(1), L<Module::Build::Cookbook>, L<Module::Build::Authoring>,
1074 L<Module::Build::API>, L<ExtUtils::MakeMaker>, L<YAML>
1076 F<META.yml> Specification:
1077 L<http://module-build.sourceforge.net/META-spec-current.html>
1079 L<http://www.dsmit.com/cons/>
1081 L<http://search.cpan.org/dist/PerlBuildSystem/>