lib(3pm)
NAME
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. - To avoid memory leaks, all trailing duplicate entries in @INC are
removed. - 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. - The "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. - 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;
CAVEATS
- In order to keep lib.pm small and simple, it only works with Unix
filepaths. This doesn't mean it only works on Unix, but non-Unix users must first translate their file paths to Unix conventions. - # VMS users wanting to put [.stuff.moo] into
# their @INC would write
use lib 'stuff/moo';
NOTES
In the future, this module will likely use File::Spec for determining
paths, as it does now for Mac OS (where Unix-style or Mac-style paths
work, and Unix-style paths are converted properly to Mac-style paths
before being added to @INC).
SEE ALSO
FindBin - optional module which deals with paths relative to the source
file.
AUTHOR
- Tim Bunce, 2nd June 1995.