lib - manipulate @INC at compile time
SYNOPSIS
use lib LIST;
no lib LIST;
DESCRIPTION
This is a small simple module which simplifies the
manipulation of @INC at compile time.
It is typically used to add extra directories to perl's
search path so that later use or require statements will
find modules which are not located on perl's default
search path.
ADDING DIRECTORIES TO @INC
The parameters to use lib are added to the start of the
perl search path. Saying
use lib LIST;
is 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).
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 added yourself or which you are
certain are not needed by other modules in your script.
Other modules may have added directories which they need
for correct operation.
By default the no lib statement deletes the 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.
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).
RESTORING ORIGINAL @INC
When the lib module is first loaded it records the current
value of @INC in an array @lib::ORIG_INC. To restore @INC
to that value you can say
@INC = @lib::ORIG_INC;
SEE ALSO
FindBin - optional module which deals with paths relative
to the source file.
AUTHOR
Tim Bunce, 2nd June 1995.