[win32] merge change#887 from maintbranch

[p5sagit/p5-mst-13.2.git] / lib / lib.pm

diff --git a/lib/lib.pm b/lib/lib.pm
index a0fe89b..4d32f96 100644 (file)
--- a/lib/lib.pm
+++ b/lib/lib.pm
@@ -1,12 +1,31 @@
 package lib;
 
-@ORIG_INC = ();                # (avoid typo warning)
+use vars qw(@ORIG_INC);
+use Config;
+
+my $archname = $Config{'archname'};
+
 @ORIG_INC = @INC;      # take a handy copy of 'original' value
 
 
 sub import {
     shift;
-    unshift(@INC, @_);
+    foreach (reverse @_) {
+       ## Ignore this if not defined.
+       next unless defined($_);
+       if ($_ eq '') {
+           require Carp;
+           Carp::carp("Empty compile time value given to use lib");
+                                                       # at foo.pl line ...
+       }
+       unshift(@INC, $_);
+       # Put a corresponding archlib directory infront of $_ if it
+       # looks like $_ has an archlib directory below it.
+       if (-d "$_/$archname") {
+           unshift(@INC, "$_/$archname")    if -d "$_/$archname/auto";
+           unshift(@INC, "$_/$archname/$]") if -d "$_/$archname/$]/auto";
+       }
+    }
 }
 
 
@@ -15,7 +34,10 @@ sub unimport {
     my $mode = shift if $_[0] =~ m/^:[A-Z]+/;
 
     my %names;
-    foreach(@_) { ++$names{$_} };
+    foreach(@_) {
+       ++$names{$_};
+       ++$names{"$_/$archname"} if -d "$_/$archname/auto";
+    }
 
     if ($mode and $mode eq ':ALL') {
        # Remove ALL instances of each named directory.
@@ -26,6 +48,7 @@ sub unimport {
     }
 }
 
+1;
 __END__
 
 =head1 NAME
@@ -47,7 +70,6 @@ It is typically used to add extra directories to perl's search path so
 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
 
 The parameters to C<use lib> are added to the start of the perl search
@@ -55,10 +77,17 @@ path. Saying
 
     use lib LIST;
 
-is the same as saying
+is I<almost> the same as saying
 
     BEGIN { unshift(@INC, LIST) }
 
+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 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).
 
 =head2 DELETING DIRECTORIES FROM @INC
 
@@ -77,23 +106,26 @@ specify ':ALL' as the first parameter of C<no lib>. For example:
 
     no lib qw(:ALL .);
 
+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
 
 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
-can say either
+can say
 
     @INC = @lib::ORIG_INC;
 
-or
-
-    no  lib @INC;
-    use lib @lib::ORIG_INC;
 
 =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