package lib;
+use 5.005_64;
use Config;
-my $archname = $Config{'archname'};
-
-@ORIG_INC = (); # (avoid typo warning)
-@ORIG_INC = @INC; # take a handy copy of 'original' value
+my $archname = defined($Config{'archname'}) ? $Config{'archname'} : '';
+my $ver = defined($Config{'version'}) ? $Config{'version'} : '';
+my @inc_version_list = defined($Config{'inc_version_list'}) ?
+ reverse split / /, $Config{'inc_version_list'} : ();
+our @ORIG_INC = @INC; # take a handy copy of 'original' value
+our $VERSION = '0.5564';
sub import {
shift;
+
+ my %names;
foreach (reverse @_) {
+ if ($_ eq '') {
+ require Carp;
+ Carp::carp("Empty compile time value given to use lib");
+ }
+ if (-e && ! -d _) {
+ require Carp;
+ Carp::carp("Parameter to use lib must be directory, not file");
+ }
unshift(@INC, $_);
+ # Add any previous version directories we found at configure time
+ foreach my $incver (@inc_version_list)
+ {
+ unshift(@INC, "$_/$incver") if -d "$_/$incver";
+ }
# Put a corresponding archlib directory infront of $_ if it
# looks like $_ has an archlib directory below it.
- unshift(@INC, "$_/$archname") if -d "$_/$archname/auto";
+ unshift(@INC, "$_/$ver") if -d "$_/$ver";
+ unshift(@INC, "$_/$ver/$archname") if -d "$_/$ver/$archname";
}
+
+ # remove trailing duplicates
+ @INC = grep { ++$names{$_} == 1 } @INC;
+ return;
}
sub unimport {
shift;
- my $mode = shift if $_[0] =~ m/^:[A-Z]+/;
my %names;
- foreach(@_) {
+ foreach (@_) {
++$names{$_};
++$names{"$_/$archname"} if -d "$_/$archname/auto";
}
- if ($mode and $mode eq ':ALL') {
- # Remove ALL instances of each named directory.
- @INC = grep { !exists $names{$_} } @INC;
- } else {
- # Remove INITIAL instance(s) of each named directory.
- @INC = grep { --$names{$_} < 0 } @INC;
- }
+ # Remove ALL instances of each named directory.
+ @INC = grep { !exists $names{$_} } @INC;
+ return;
}
1;
that later C<use> or C<require> statements will find modules which are
not located on perl's default search path.
-
-=head2 ADDING DIRECTORIES TO @INC
+=head2 Adding directories to @INC
The parameters to C<use lib> are added to the start of the perl search
path. Saying
If so the $dir/$archname directory is assumed to be a corresponding
architecture specific directory and is added to @INC in front of $dir.
-If LIST includes both $dir and $dir/$archname then $dir/$archname will
-be added to @INC twice (if $dir/$archname/auto exists).
+To avoid memory leaks, all trailing duplicate entries in @INC are
+removed.
-
-=head2 DELETING DIRECTORIES FROM @INC
+=head2 Deleting directories from @INC
You should normally only add directories to @INC. If you need to
delete directories from @INC take care to only delete those which you
in your script. Other modules may have added directories which they
need for correct operation.
-By default the C<no lib> statement deletes the I<first> instance of
-each named directory from @INC. To delete multiple instances of the
-same name from @INC you can specify the name multiple times.
-
-To delete I<all> instances of I<all> the specified names from @INC you can
-specify ':ALL' as the first parameter of C<no lib>. For example:
-
- no lib qw(:ALL .);
+The C<no lib> statement deletes all instances of each named directory
+from @INC.
For each directory in LIST (called $dir here) the lib module also
checks to see if a directory called $dir/$archname/auto exists.
If so the $dir/$archname directory is assumed to be a corresponding
architecture specific directory and is also deleted from @INC.
-If LIST includes both $dir and $dir/$archname then $dir/$archname will
-be deleted from @INC twice (if $dir/$archname/auto exists).
-
-
-=head2 RESTORING ORIGINAL @INC
+=head2 Restoring original @INC
When the lib module is first loaded it records the current value of @INC
in an array C<@lib::ORIG_INC>. To restore @INC to that value you
=head1 SEE ALSO
-AddINC - optional module which deals with paths relative to the source file.
+FindBin - optional module which deals with paths relative to the source file.
=head1 AUTHOR
Tim Bunce, 2nd June 1995.
=cut
-