2 use File::Basename qw(&basename &dirname);
8 my $file = basename($0, '.PL');
9 $file =~ s/_(pm)$/.$1/i;
14 my $Config_inc_version_list;
16 # Expand the variables only if explicitly requested
17 # or if a previously installed lib.pm does this, too
18 # because otherwise relocating Perl becomes much harder.
20 my $expand_config_vars = 0;
21 if ($ENV{PERL_BUILD_EXPAND_CONFIG_VARS}) {
22 $expand_config_vars = 1;
24 elsif (exists $ENV{PERL_BUILD_EXPAND_CONFIG_VARS}) {
25 $expand_config_vars = 0;
30 my $lib_file = $INC{"lib.pm"};
31 open my $fh, '<', $lib_file
32 or die "Could not open file '$lib_file' for reading: $!";
33 my $ConfigRegex = qr/(?:use|require)\s+Config(?:\s+|;)/;
35 while (defined($_ = <$fh>)) {
36 # crude heuristics to check that we were using Config
37 if (/^\s*$ConfigRegex/ || /^\s*eval.*$ConfigRegex/) {
42 $expand_config_vars = $found_config ? 0 : 1;
44 $expand_config_vars = 0 if $@;
47 if ($expand_config_vars) {
49 $Config_archname = qq('$Config{archname}');
50 $Config_version = qq('$Config{version}');
51 my @Config_inc_version_list =
52 reverse split / /, $Config{inc_version_list};
53 $Config_inc_version_list =
54 @Config_inc_version_list ?
55 qq(qw(@Config_inc_version_list)) : q(());
57 $useConfig = 'use Config;';
58 $Config_archname = q($Config{archname});
59 $Config_version = q($Config{version});
60 $Config_inc_version_list =
61 q(reverse split / /, $Config{inc_version_list});
64 open OUT,'>', $file or die "Can't create $file: $!";
66 print "Extracting $file (with variable substitutions)\n";
68 # In this section, perl variables will be expanded during extraction.
69 # You can use $Config{...} to use Configure variables.
71 print OUT <<"!GROK!THIS!";
74 # THIS FILE IS AUTOMATICALLY GENERATED FROM lib_pm.PL.
75 # ANY CHANGES TO THIS FILE WILL BE OVERWRITTEN BY THE NEXT PERL BUILD.
81 my \$archname = $Config_archname;
82 my \$version = $Config_version;
83 my \@inc_version_list = $Config_inc_version_list;
86 print OUT <<'!NO!SUBS!';
88 our @ORIG_INC = @INC; # take a handy copy of 'original' value
89 our $VERSION = '0.64';
95 foreach (reverse @_) {
96 my $path = $_; # we'll be modifying it, so break the alias
99 Carp::carp("Empty compile time value given to use lib");
102 if ($path !~ /\.par$/i && -e $path && ! -d _) {
104 Carp::carp("Parameter to use lib must be directory, not file");
106 unshift(@INC, $path);
107 # Add any previous version directories we found at configure time
108 foreach my $incver (@inc_version_list)
110 my $dir = "$path/$incver";
111 unshift(@INC, $dir) if -d $dir;
113 # Put a corresponding archlib directory in front of $path if it
114 # looks like $path has an archlib directory below it.
115 my($arch_auto_dir, $arch_dir, $version_dir, $version_arch_dir)
117 unshift(@INC, $arch_dir) if -d $arch_auto_dir;
118 unshift(@INC, $version_dir) if -d $version_dir;
119 unshift(@INC, $version_arch_dir) if -d $version_arch_dir;
122 # remove trailing duplicates
123 @INC = grep { ++$names{$_} == 1 } @INC;
132 foreach my $path (@_) {
133 my($arch_auto_dir, $arch_dir, $version_dir, $version_arch_dir)
136 ++$names{$arch_dir} if -d $arch_auto_dir;
137 ++$names{$version_dir} if -d $version_dir;
138 ++$names{$version_arch_dir} if -d $version_arch_dir;
141 # Remove ALL instances of each named directory.
142 @INC = grep { !exists $names{$_} } @INC;
148 my($arch_auto_dir, $arch_dir, $version_dir, $version_arch_dir);
150 $arch_auto_dir = "$dir/$archname/auto";
151 $arch_dir = "$dir/$archname";
152 $version_dir = "$dir/$version";
153 $version_arch_dir = "$dir/$version/$archname";
155 return($arch_auto_dir, $arch_dir, $version_dir, $version_arch_dir);
163 lib - manipulate @INC at compile time
173 This is a small simple module which simplifies the manipulation of @INC
176 It is typically used to add extra directories to perl's search path so
177 that later C<use> or C<require> statements will find modules which are
178 not located on perl's default search path.
180 =head2 Adding directories to @INC
182 The parameters to C<use lib> are added to the start of the perl search
187 is I<almost> the same as saying
189 BEGIN { unshift(@INC, LIST) }
191 For each directory in LIST (called $dir here) the lib module also
192 checks to see if a directory called $dir/$archname/auto exists.
193 If so the $dir/$archname directory is assumed to be a corresponding
194 architecture specific directory and is added to @INC in front of $dir.
195 lib.pm also checks if directories called $dir/$version and $dir/$version/$archname
196 exist and adds these directories to @INC.
198 The current value of C<$archname> can be found with this command:
202 The corresponding command to get the current value of C<$version> is:
206 To avoid memory leaks, all trailing duplicate entries in @INC are
209 =head2 Deleting directories from @INC
211 You should normally only add directories to @INC. If you need to
212 delete directories from @INC take care to only delete those which you
213 added yourself or which you are certain are not needed by other modules
214 in your script. Other modules may have added directories which they
215 need for correct operation.
217 The C<no lib> statement deletes all instances of each named directory
220 For each directory in LIST (called $dir here) the lib module also
221 checks to see if a directory called $dir/$archname/auto exists.
222 If so the $dir/$archname directory is assumed to be a corresponding
223 architecture specific directory and is also deleted from @INC.
225 =head2 Restoring original @INC
227 When the lib module is first loaded it records the current value of @INC
228 in an array C<@lib::ORIG_INC>. To restore @INC to that value you
231 @INC = @lib::ORIG_INC;
235 In order to keep lib.pm small and simple, it only works with Unix
236 filepaths. This doesn't mean it only works on Unix, but non-Unix
237 users must first translate their file paths to Unix conventions.
239 # VMS users wanting to put [.stuff.moo] into
240 # their @INC would write
245 In the future, this module will likely use File::Spec for determining
246 paths, as it does now for Mac OS (where Unix-style or Mac-style paths
247 work, and Unix-style paths are converted properly to Mac-style paths
248 before being added to @INC).
250 If you try to add a file to @INC as follows:
252 use lib 'this_is_a_file.txt';
254 C<lib> will warn about this. The sole exceptions are files with the
255 C<.par> extension which are intended to be used as libraries.
259 FindBin - optional module which deals with paths relative to the source file.
261 PAR - optional module which can treat C<.par> files as Perl libraries.
265 Tim Bunce, 2nd June 1995.
267 C<lib> is maintained by the perl5-porters. Please direct
268 any questions to the canonical mailing list. Anything that
269 is applicable to the CPAN release can be sent to its maintainer,
272 Maintainer: The Perl5-Porters <perl5-porters@perl.org>
274 Maintainer of the CPAN release: Steffen Mueller <smueller@cpan.org>
276 =head1 COPYRIGHT AND LICENSE
278 This package has been part of the perl core since perl 5.001.
279 It has been released separately to CPAN so older installations
280 can benefit from bug fixes.
282 This package has the same copyright and license as the perl core.
287 close OUT or die "Can't close $file: $!";