lib - manipulate @INC
at compile time
use lib LIST;
no lib LIST;
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.
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).
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.
To delete all instances of all the specified names from @INC
you can specify
':ALL' as the first parameter of 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).
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;
FindBin - optional module which deals with paths relative to the source file.
Tim Bunce, 2nd June 1995.
If rather than formatting bugs, you encounter substantive content errors in these documents, such as mistakes in the explanations or code, please use the perlbug utility included with the Perl distribution.