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);
18 $VERSION = '0.31012_01';
19 $VERSION = eval $VERSION;
21 # Okay, this is the brute-force method of finding out what kind of
22 # platform we're on. I don't know of a systematic way. These values
23 # came from the latest (bleadperl) perlport.pod.
74 # Inserts the given module into the @ISA hierarchy between
75 # Module::Build and its immediate parent
76 sub _interpose_module {
77 my ($self, $mod) = @_;
83 while (@{"${top_class}::ISA"}) {
84 last if ${"${top_class}::ISA"}[0] eq $ISA[0];
85 $top_class = ${"${top_class}::ISA"}[0];
88 @{"${top_class}::ISA"} = @ISA;
92 if (grep {-e File::Spec->catfile($_, qw(Module Build Platform), $^O) . '.pm'} @INC) {
93 __PACKAGE__->_interpose_module("Module::Build::Platform::$^O");
95 } elsif (exists $OSTYPES{$^O}) {
96 __PACKAGE__->_interpose_module("Module::Build::Platform::$OSTYPES{$^O}");
99 warn "Unknown OS type '$^O' - using default settings\n";
102 sub os_type { $OSTYPES{$^O} }
104 sub is_vmsish { return ((os_type() || '') eq 'VMS') }
105 sub is_windowsish { return ((os_type() || '') eq 'Windows') }
106 sub is_unixish { return ((os_type() || '') eq 'Unix') }
115 Module::Build - Build and install Perl modules
120 Standard process for building & installing modules:
127 Or, if you're on a platform (like DOS or Windows) that doesn't require
128 the "./" notation, you can do this:
138 C<Module::Build> is a system for building, testing, and installing
139 Perl modules. It is meant to be an alternative to
140 C<ExtUtils::MakeMaker>. Developers may alter the behavior of the
141 module through subclassing in a much more straightforward way than
142 with C<MakeMaker>. It also does not require a C<make> on your system
143 - most of the C<Module::Build> code is pure-perl and written in a very
144 cross-platform way. In fact, you don't even need a shell, so even
145 platforms like MacOS (traditional) can use it fairly easily. Its only
146 prerequisites are modules that are included with perl 5.6.0, and it
147 works fine on perl 5.005 if you can install a few additional modules.
149 See L<"MOTIVATIONS"> for more comparisons between C<ExtUtils::MakeMaker>
150 and C<Module::Build>.
152 To install C<Module::Build>, and any other module that uses
153 C<Module::Build> for its installation process, do the following:
155 perl Build.PL # 'Build.PL' script creates the 'Build' script
156 ./Build # Need ./ to ensure we're using this "Build" script
157 ./Build test # and not another one that happens to be in the PATH
160 This illustrates initial configuration and the running of three
161 'actions'. In this case the actions run are 'build' (the default
162 action), 'test', and 'install'. Other actions defined so far include:
170 distcheck pure_install
180 install versioninstall
183 You can run the 'help' action for a complete list of actions.
186 =head1 GUIDE TO DOCUMENTATION
188 The documentation for C<Module::Build> is broken up into three sections:
192 =item General Usage (L<Module::Build>)
194 This is the document you are currently reading. It describes basic
195 usage and background information. Its main purpose is to assist the
196 user who wants to learn how to invoke and control C<Module::Build>
197 scripts at the command line.
199 =item Authoring Reference (L<Module::Build::Authoring>)
201 This document describes the structure and organization of
202 C<Module::Build>, and the relevant concepts needed by authors who are
203 writing F<Build.PL> scripts for a distribution or controlling
204 C<Module::Build> processes programmatically.
206 =item API Reference (L<Module::Build::API>)
208 This is a reference to the C<Module::Build> API.
210 =item Cookbook (L<Module::Build::Cookbook>)
212 This document demonstrates how to accomplish many common tasks. It
213 covers general command line usage and authoring of F<Build.PL>
214 scripts. Includes working examples.
221 There are some general principles at work here. First, each task when
222 building a module is called an "action". These actions are listed
223 above; they correspond to the building, testing, installing,
224 packaging, etc., tasks.
226 Second, arguments are processed in a very systematic way. Arguments
227 are always key=value pairs. They may be specified at C<perl Build.PL>
228 time (i.e. C<perl Build.PL destdir=/my/secret/place>), in which case
229 their values last for the lifetime of the C<Build> script. They may
230 also be specified when executing a particular action (i.e.
231 C<Build test verbose=1>), in which case their values last only for the
232 lifetime of that command. Per-action command line parameters take
233 precedence over parameters specified at C<perl Build.PL> time.
235 The build process also relies heavily on the C<Config.pm> module.
236 If the user wishes to override any of the
237 values in C<Config.pm>, she may specify them like so:
239 perl Build.PL --config cc=gcc --config ld=gcc
241 The following build actions are provided by default.
249 If you run the C<Build> script without any arguments, it runs the
250 C<build> action, which in turn runs the C<code> and C<docs> actions.
252 This is analogous to the MakeMaker 'make all' target.
258 This action will clean up any files that the build process may have
259 created, including the C<blib/> directory (but not including the
260 C<_build/> directory and the C<Build> script itself).
266 This action builds your codebase.
268 By default it just creates a C<blib/> directory and copies any C<.pm>
269 and C<.pod> files from your C<lib/> directory into the C<blib/>
270 directory. It also compiles any C<.xs> files from C<lib/> and places
271 them in C<blib/>. Of course, you need a working C compiler (probably
272 the same one that built perl itself) for the compilation to work
275 The C<code> action also runs any C<.PL> files in your F<lib/>
276 directory. Typically these create other files, named the same but
277 without the C<.PL> ending. For example, a file F<lib/Foo/Bar.pm.PL>
278 could create the file F<lib/Foo/Bar.pm>. The C<.PL> files are
279 processed first, so any C<.pm> files (or other kinds that we deal
280 with) will get copied correctly.
292 This action will compare the files about to be installed with their
293 installed counterparts. For .pm and .pod files, a diff will be shown
294 (this currently requires a 'diff' program to be in your PATH). For
295 other files like compiled binary files, we simply report whether they
298 A C<flags> parameter may be passed to the action, which will be passed
299 to the 'diff' program. Consult your 'diff' documentation for the
300 parameters it will accept - a good one is C<-u>:
302 ./Build diff flags=-u
308 This action is helpful for module authors who want to package up their
309 module for source distribution through a medium like CPAN. It will create a
310 tarball of the files listed in F<MANIFEST> and compress the tarball using
313 By default, this action will use the external C<tar> and C<gzip>
314 executables on Unix-like platforms, and the C<Archive::Tar> module
315 elsewhere. However, you can force it to use whatever executable you
316 want by supplying an explicit C<tar> (and optional C<gzip>) parameter:
318 ./Build dist --tar C:\path\to\tar.exe --gzip C:\path\to\zip.exe
324 Reports which files are in the build directory but not in the
325 F<MANIFEST> file, and vice versa. (See L<manifest> for details.)
331 Performs the 'realclean' action and then the 'distcheck' action.
337 Creates a "distribution directory" named C<$dist_name-$dist_version>
338 (if that directory already exists, it will be removed first), then
339 copies all the files listed in the F<MANIFEST> file to that directory.
340 This directory is what the distribution tarball is created from.
346 Creates the F<META.yml> file that describes the distribution.
348 F<META.yml> is a file containing various bits of "metadata" about the
349 distribution. The metadata includes the distribution name, version,
350 abstract, prerequisites, license, and various other data about the
351 distribution. This file is created as F<META.yml> in YAML format.
352 It is recommended that the C<YAML> module be installed to create it.
353 If the C<YAML> module is not installed, an internal module supplied
354 with Module::Build will be used to write the META.yml file, and this
355 will most likely be fine.
357 F<META.yml> file must also be listed in F<MANIFEST> - if it's not, a
358 warning will be issued.
360 The current version of the F<META.yml> specification can be found at
361 L<http://module-build.sourceforge.net/META-spec-current.html>
367 Uses C<Module::Signature> to create a SIGNATURE file for your
368 distribution, and adds the SIGNATURE file to the distribution's
375 Performs the 'distdir' action, then switches into that directory and
376 runs a C<perl Build.PL>, followed by the 'build' and 'test' actions in
383 This will generate documentation (e.g. Unix man pages and html
384 documents) for any installable items under B<blib/> that
385 contain POD. If there are no C<bindoc> or C<libdoc> installation
386 targets defined (as will be the case on systems that don't support
387 Unix manpages) no action is taken for manpages. If there are no
388 C<binhtml> or C<libhtml> installation targets defined no action is
389 taken for html documents.
395 This is just like the C<install> action, but it won't actually do
396 anything, it will just report what it I<would> have done if you had
397 actually run the C<install> action.
403 This action will simply print out a message that is meant to help you
404 use the build process. It will show you a list of available build
407 With an optional argument specifying an action name (e.g. C<Build help
408 test>), the 'help' action will show you any POD documentation it can
409 find for that action.
415 This will generate HTML documentation for any binary or library files
416 under B<blib/> that contain POD. The HTML documentation will only be
417 installed if the install paths can be determined from values in
418 C<Config.pm>. You can also supply or override install paths on the
419 command line by specifying C<install_path> values for the C<binhtml>
420 and/or C<libhtml> installation targets.
426 This action will use C<ExtUtils::Install> to install the files from
427 C<blib/> into the system. See L<"INSTALL PATHS">
428 for details about how Module::Build determines where to install
429 things, and how to influence this process.
431 If you want the installation process to look around in C<@INC> for
432 other versions of the stuff you're installing and try to delete it,
433 you can use the C<uninst> parameter, which tells C<ExtUtils::Install> to
436 ./Build install uninst=1
438 This can be a good idea, as it helps prevent multiple versions of a
439 module from being present on your system, which can be a confusing
446 This is an action intended for use by module authors, not people
447 installing modules. It will bring the F<MANIFEST> up to date with the
448 files currently present in the distribution. You may use a
449 F<MANIFEST.SKIP> file to exclude certain files or directories from
450 inclusion in the F<MANIFEST>. F<MANIFEST.SKIP> should contain a bunch
451 of regular expressions, one per line. If a file in the distribution
452 directory matches any of the regular expressions, it won't be included
455 The following is a reasonable F<MANIFEST.SKIP> starting point, you can
456 add your own stuff to it:
466 See the L<distcheck> and L<skipcheck> actions if you want to find out
467 what the C<manifest> action would do, without actually doing anything.
473 This will generate man pages for any binary or library files under
474 B<blib/> that contain POD. The man pages will only be installed if the
475 install paths can be determined from values in C<Config.pm>. You can
476 also supply or override install paths by specifying there values on
477 the command line with the C<bindoc> and C<libdoc> installation
484 Generates a PAR binary distribution for use with L<PAR> or L<PAR::Dist>.
486 It requires that the PAR::Dist module (version 0.17 and up) is
487 installed on your system.
493 Build a PPD file for your distribution.
495 This action takes an optional argument C<codebase> which is used in
496 the generated ppd file to specify the (usually relative) URL of the
497 distribution. By default, this value is the distribution name without
498 any path information.
502 ./Build ppd --codebase "MSWin32-x86-multi-thread/Module-Build-0.21.tar.gz"
508 Generates a PPM binary distribution and a PPD description file. This
509 action also invokes the 'ppd' action, so it can accept the same
510 C<codebase> argument described under that action.
512 This uses the same mechanism as the C<dist> action to tar & zip its
513 output, so you can supply C<tar> and/or C<gzip> parameters to affect
520 This action prints out a list of all prerequisites, the versions required, and
521 the versions actually installed. This can be useful for reviewing the
522 configuration of your system prior to a build, or when compiling data to send
529 This action is identical to the C<install> action. In the future,
530 though, when C<install> starts writing to the file
531 F<$(INSTALLARCHLIB)/perllocal.pod>, C<pure_install> won't, and that
532 will be the only difference between them.
538 This action is just like the C<clean> action, but also removes the
539 C<_build> directory and the C<Build> script. If you run the
540 C<realclean> action, you are essentially starting over, so you will
541 have to re-create the C<Build> script again.
547 This is just like the C<test> action, but doesn't actually build the
548 distribution first, and doesn't add F<blib/> to the load path, and
549 therefore will test against a I<previously> installed version of the
550 distribution. This can be used to verify that a certain installed
551 distribution still works, or to see whether newer versions of a
552 distribution still pass the old regression tests, and so on.
558 Reports which files are skipped due to the entries in the
559 F<MANIFEST.SKIP> file (See L<manifest> for details)
565 This will use C<Test::Harness> or C<TAP::Harness> to run any regression
566 tests and report their results. Tests can be defined in the standard
567 places: a file called C<test.pl> in the top-level directory, or several
568 files ending with C<.t> in a C<t/> directory.
570 If you want tests to be 'verbose', i.e. show details of test execution
571 rather than just summary information, pass the argument C<verbose=1>.
573 If you want to run tests under the perl debugger, pass the argument
576 If you want to have Module::Build find test files with different file
577 name extensions, pass the C<test_file_exts> argument with an array
578 of extensions, such as C<[qw( .t .s .z )]>.
580 If you want test to be run by C<TAP::Harness>, rather than C<Test::Harness>,
581 pass the argument C<tap_harness_args> as an array reference of arguments to
582 pass to the TAP::Harness constructor.
584 In addition, if a file called C<visual.pl> exists in the top-level
585 directory, this file will be executed as a Perl script and its output
586 will be shown to the user. This is a good place to put speed tests or
587 other tests that don't use the C<Test::Harness> format for output.
589 To override the choice of tests to run, you may pass a C<test_files>
590 argument whose value is a whitespace-separated list of test scripts to
591 run. This is especially useful in development, when you only want to
592 run a single test to see whether you've squashed a certain bug yet:
594 ./Build test --test_files t/something_failing.t
596 You may also pass several C<test_files> arguments separately:
598 ./Build test --test_files t/one.t --test_files t/two.t
600 or use a C<glob()>-style pattern:
602 ./Build test --test_files 't/01-*.t'
608 [Note: the 'testall' action and the code snippets below are currently
610 L<"http://www.nntp.perl.org/group/perl.module.build/2007/03/msg584.html"> ]
612 Runs the C<test> action plus each of the C<test$type> actions defined by
613 the keys of the C<test_types> parameter.
615 Currently, you need to define the ACTION_test$type method yourself and
616 enumerate them in the test_types parameter.
618 my $mb = Module::Build->subclass(
620 sub ACTION_testspecial { shift->generic_test(type => 'special'); }
621 sub ACTION_testauthor { shift->generic_test(type => 'author'); }
627 author => ['.at', '.pt' ],
635 Runs the C<test> action using C<Devel::Cover>, generating a
636 code-coverage report showing which parts of the code were actually
637 exercised during the tests.
639 To pass options to C<Devel::Cover>, set the C<$DEVEL_COVER_OPTIONS>
640 environment variable:
642 DEVEL_COVER_OPTIONS=-ignore,Build ./Build testcover
648 This is a synonym for the 'test' action with the C<debugger=1>
655 This checks all the files described in the C<docs> action and
656 produces C<Test::Harness>-style output. If you are a module author,
657 this is useful to run before creating a new release.
659 =item testpodcoverage
663 This checks the pod coverage of the distribution and
664 produces C<Test::Harness>-style output. If you are a module author,
665 this is useful to run before creating a new release.
671 ** Note: since C<only.pm> is so new, and since we just recently added
672 support for it here too, this feature is to be considered
675 If you have the C<only.pm> module installed on your system, you can
676 use this action to install a module into the version-specific library
677 trees. This means that you can have several versions of the same
678 module installed and C<use> a specific one like this:
680 use only MyModule => 0.55;
682 To override the default installation libraries in C<only::config>,
683 specify the C<versionlib> parameter when you run the C<Build.PL> script:
685 perl Build.PL --versionlib /my/version/place/
687 To override which version the module is installed as, specify the
688 C<versionlib> parameter when you run the C<Build.PL> script:
690 perl Build.PL --version 0.50
692 See the C<only.pm> documentation for more information on
693 version-specific installs.
700 =head2 Command Line Options
702 The following options can be used during any invocation of C<Build.PL>
703 or the Build script, during any action. For information on other
704 options specific to an action, see the documentation for the
707 NOTE: There is some preliminary support for options to use the more
708 familiar long option style. Most options can be preceded with the
709 C<--> long option prefix, and the underscores changed to dashes
710 (e.g. --use-rcfile). Additionally, the argument to boolean options is
711 optional, and boolean options can be negated by prefixing them with
712 'no' or 'no-' (e.g. --noverbose or --no-verbose).
718 Suppress informative messages on output.
722 Load the F<~/.modulebuildrc> option file. This option can be set to
723 false to prevent the custom resource file from being loaded.
727 Display extra information about the Build on output.
729 =item allow_mb_mismatch
731 Suppresses the check upon startup that the version of Module::Build
732 we're now running under is the same version that was initially invoked
733 when building the distribution (i.e. when the C<Build.PL> script was
734 first run). Use with caution.
739 =head2 Default Options File (F<.modulebuildrc>)
743 When Module::Build starts up, it will look first for a file,
744 F<$ENV{HOME}/.modulebuildrc>. If it's not found there, it will look
745 in the the F<.modulebuildrc> file in the directories referred to by
746 the environment variables C<HOMEDRIVE> + C<HOMEDIR>, C<USERPROFILE>,
747 C<APPDATA>, C<WINDIR>, C<SYS$LOGIN>. If the file exists, the options
748 specified there will be used as defaults, as if they were typed on the
749 command line. The defaults can be overridden by specifying new values
752 The action name must come at the beginning of the line, followed by any
753 amount of whitespace and then the options. Options are given the same
754 as they would be on the command line. They can be separated by any
755 amount of whitespace, including newlines, as long there is whitespace at
756 the beginning of each continued line. Anything following a hash mark (C<#>)
757 is considered a comment, and is stripped before parsing. If more than
758 one line begins with the same action name, those lines are merged into
761 Besides the regular actions, there are two special pseudo-actions: the
762 key C<*> (asterisk) denotes any global options that should be applied
763 to all actions, and the key 'Build_PL' specifies options to be applied
764 when you invoke C<perl Build.PL>.
766 * verbose=1 # global options
768 install --install_base /home/ken
769 --install_path html=/home/ken/docs/html
771 If you wish to locate your resource file in a different location, you
772 can set the environment variable 'MODULEBUILDRC' to the complete
773 absolute path of the file containing your options.
780 When you invoke Module::Build's C<build> action, it needs to figure
781 out where to install things. The nutshell version of how this works
782 is that default installation locations are determined from
783 F<Config.pm>, and they may be overridden by using the C<install_path>
784 parameter. An C<install_base> parameter lets you specify an
785 alternative installation root like F</home/foo>, and a C<destdir> lets
786 you specify a temporary installation directory like F</tmp/install> in
787 case you want to create bundled-up installable packages.
789 Natively, Module::Build provides default installation locations for
790 the following types of installable items:
796 Usually pure-Perl module files ending in F<.pm>.
800 "Architecture-dependent" module files, usually produced by compiling
801 XS, Inline, or similar code.
805 Programs written in pure Perl. In order to improve reuse, try to make
806 these as small as possible - put the code into modules whenever
811 "Architecture-dependent" executable programs, i.e. compiled C code or
812 something. Pretty rare to see this in a perl distribution, but it
817 Documentation for the stuff in C<script> and C<bin>. Usually
818 generated from the POD in those files. Under Unix, these are manual
819 pages belonging to the 'man1' category.
823 Documentation for the stuff in C<lib> and C<arch>. This is usually
824 generated from the POD in F<.pm> files. Under Unix, these are manual
825 pages belonging to the 'man3' category.
829 This is the same as C<bindoc> above, but applies to html documents.
833 This is the same as C<bindoc> above, but applies to html documents.
837 Four other parameters let you control various aspects of how
838 installation paths are determined:
844 The default destinations for these installable things come from
845 entries in your system's C<Config.pm>. You can select from three
846 different sets of default locations by setting the C<installdirs>
847 parameter as follows:
849 'installdirs' set to:
852 uses the following defaults from Config.pm:
854 lib => installprivlib installsitelib installvendorlib
855 arch => installarchlib installsitearch installvendorarch
856 script => installscript installsitebin installvendorbin
857 bin => installbin installsitebin installvendorbin
858 bindoc => installman1dir installsiteman1dir installvendorman1dir
859 libdoc => installman3dir installsiteman3dir installvendorman3dir
860 binhtml => installhtml1dir installsitehtml1dir installvendorhtml1dir [*]
861 libhtml => installhtml3dir installsitehtml3dir installvendorhtml3dir [*]
863 * Under some OS (eg. MSWin32) the destination for html documents is
864 determined by the C<Config.pm> entry C<installhtmldir>.
866 The default value of C<installdirs> is "site". If you're creating
867 vendor distributions of module packages, you may want to do something
870 perl Build.PL --installdirs vendor
874 ./Build install --installdirs vendor
876 If you're installing an updated version of a module that was included
877 with perl itself (i.e. a "core module"), then you may set
878 C<installdirs> to "core" to overwrite the module in its present
881 (Note that the 'script' line is different from MakeMaker -
882 unfortunately there's no such thing as "installsitescript" or
883 "installvendorscript" entry in C<Config.pm>, so we use the
884 "installsitebin" and "installvendorbin" entries to at least get the
885 general location right. In the future, if C<Config.pm> adds some more
886 appropriate entries, we'll start using those.)
890 Once the defaults have been set, you can override them.
892 On the command line, that would look like this:
894 perl Build.PL --install_path lib=/foo/lib --install_path arch=/foo/lib/arch
898 ./Build install --install_path lib=/foo/lib --install_path arch=/foo/lib/arch
902 You can also set the whole bunch of installation paths by supplying the
903 C<install_base> parameter to point to a directory on your system. For
904 instance, if you set C<install_base> to "/home/ken" on a Linux
905 system, you'll install as follows:
907 lib => /home/ken/lib/perl5
908 arch => /home/ken/lib/perl5/i386-linux
909 script => /home/ken/bin
911 bindoc => /home/ken/man/man1
912 libdoc => /home/ken/man/man3
913 binhtml => /home/ken/html
914 libhtml => /home/ken/html
916 Note that this is I<different> from how MakeMaker's C<PREFIX>
917 parameter works. C<install_base> just gives you a default layout under the
918 directory you specify, which may have little to do with the
919 C<installdirs=site> layout.
921 The exact layout under the directory you specify may vary by system -
922 we try to do the "sensible" thing on each platform.
926 If you want to install everything into a temporary directory first
927 (for instance, if you want to create a directory tree that a package
928 manager like C<rpm> or C<dpkg> could create a package from), you can
929 use the C<destdir> parameter:
931 perl Build.PL --destdir /tmp/foo
935 ./Build install --destdir /tmp/foo
937 This will effectively install to "/tmp/foo/$sitelib",
938 "/tmp/foo/$sitearch", and the like, except that it will use
939 C<File::Spec> to make the pathnames work correctly on whatever
940 platform you're installing on.
944 Provided for compatibility with ExtUtils::MakeMaker's PREFIX argument.
945 C<prefix> should be used when you wish Module::Build to install your
946 modules, documentation and scripts in the same place
947 ExtUtils::MakeMaker does.
949 The following are equivalent.
951 perl Build.PL --prefix /tmp/foo
952 perl Makefile.PL PREFIX=/tmp/foo
954 Because of the very complex nature of the prefixification logic, the
955 behavior of PREFIX in MakeMaker has changed subtly over time.
956 Module::Build's --prefix logic is equivalent to the PREFIX logic found
957 in ExtUtils::MakeMaker 6.30.
959 If you do not need to retain compatibility with ExtUtils::MakeMaker or
960 are starting a fresh Perl installation we recommand you use
961 C<install_base> instead (and C<INSTALL_BASE> in ExtUtils::MakeMaker).
962 See L<Module::Build::Cookbook/Instaling in the same location as
963 ExtUtils::MakeMaker> for further information.
971 There are several reasons I wanted to start over, and not just fix
972 what I didn't like about MakeMaker:
978 I don't like the core idea of MakeMaker, namely that C<make> should be
979 involved in the build process. Here are my reasons:
985 When a person is installing a Perl module, what can you assume about
986 their environment? Can you assume they have C<make>? No, but you can
987 assume they have some version of Perl.
991 When a person is writing a Perl module for intended distribution, can
992 you assume that they know how to build a Makefile, so they can
993 customize their build process? No, but you can assume they know Perl,
994 and could customize that way.
998 For years, these things have been a barrier to people getting the
999 build/install process to do what they want.
1003 There are several architectural decisions in MakeMaker that make it
1004 very difficult to customize its behavior. For instance, when using
1005 MakeMaker you do C<use ExtUtils::MakeMaker>, but the object created in
1006 C<WriteMakefile()> is actually blessed into a package name that's
1007 created on the fly, so you can't simply subclass
1008 C<ExtUtils::MakeMaker>. There is a workaround C<MY> package that lets
1009 you override certain MakeMaker methods, but only certain explicitly
1010 preselected (by MakeMaker) methods can be overridden. Also, the method
1011 of customization is very crude: you have to modify a string containing
1012 the Makefile text for the particular target. Since these strings
1013 aren't documented, and I<can't> be documented (they take on different
1014 values depending on the platform, version of perl, version of
1015 MakeMaker, etc.), you have no guarantee that your modifications will
1016 work on someone else's machine or after an upgrade of MakeMaker or
1021 It is risky to make major changes to MakeMaker, since it does so many
1022 things, is so important, and generally works. C<Module::Build> is an
1023 entirely separate package so that I can work on it all I want, without
1024 worrying about backward compatibility.
1028 Finally, Perl is said to be a language for system administration.
1029 Could it really be the case that Perl isn't up to the task of building
1030 and installing software? Even if that software is a bunch of stupid
1031 little C<.pm> files that just need to be copied from one place to
1032 another? My sense was that we could design a system to accomplish
1033 this in a flexible, extensible, and friendly manner. Or die trying.
1040 The current method of relying on time stamps to determine whether a
1041 derived file is out of date isn't likely to scale well, since it
1042 requires tracing all dependencies backward, it runs into problems on
1043 NFS, and it's just generally flimsy. It would be better to use an MD5
1044 signature or the like, if available. See C<cons> for an example.
1046 - append to perllocal.pod
1047 - add a 'plugin' functionality
1052 Ken Williams <kwilliams@cpan.org>
1054 Development questions, bug reports, and patches should be sent to the
1055 Module-Build mailing list at <module-build@perl.org>.
1057 Bug reports are also welcome at
1058 <http://rt.cpan.org/NoAuth/Bugs.html?Dist=Module-Build>.
1060 The latest development version is available from the Subversion
1061 repository at <https://svn.perl.org/modules/Module-Build/trunk/>
1066 Copyright (c) 2001-2006 Ken Williams. All rights reserved.
1068 This library is free software; you can redistribute it and/or
1069 modify it under the same terms as Perl itself.
1074 perl(1), L<Module::Build::Cookbook>, L<Module::Build::Authoring>,
1075 L<Module::Build::API>, L<ExtUtils::MakeMaker>, L<YAML>
1077 F<META.yml> Specification:
1078 L<http://module-build.sourceforge.net/META-spec-current.html>
1080 L<http://www.dsmit.com/cons/>
1082 L<http://search.cpan.org/dist/PerlBuildSystem/>