NAME
Devel::SearchINC - Loading Perl modules from their development directories
VERSION
version 2.103460
SYNOPSIS
# export PERL5OPT=-MDevel::SearchINC=/my/dev/dir
# now use your new modules
DESCRIPTION
When developing a new module, I always start with a standard skeleton distribution directory. The directory structure is such, however, that you have to install the module first (with make install
) before you can use it in another program or module. For example, bringing in a module like so:
use My::Module;
requires the module to be somewhere in a path listed in @INC
, and the relative path is expected to be My/Module.pm
. However, h2xs
creates a structure where the module ends up in My/Module/Module.pm
.
This module tries to compensate for that. The idea is that you use()
it right at the beginning of your program so it can modify @INC
to look for modules in relative paths of the special structure mentioned above, starting with directories specified along with the use()
statement (i.e. the arguments passed to this module's import()
).
This is useful because with this module you can test your programs using your newly developed modules without having to install them just so you can use them. This is especially advantageous when you consider working on many new modules at the same time.
To automatically make your development modules available to all your scripts, you can place the following in your .bashrc
(or your shell initialization file of choice):
export PERL5OPT=-MDevel::SearchINC=/my/dev/dir
Tilde expansion is also performed.
When this module is first run, that is, when perl first consults @INC
, all candidate files are remembered in a cache (see build_cache()
). A candidate file is one whose name ends in .pm
, is not within a directory called t
, CVS
, .svn
, .git
, skel
or _build
, and is within a directory called lib
, blib/lib
or blib/arch
. This is a long-winded way of saying that it tries to find your perl module files within standard development directories.
If a directory contains a file named INC.SKIP
, this directory will be skipped.
Note that there is a small limitation for the PERL5OPT
approach: development modules can't be loaded via -M
on the perl command line. So the following won't work:
$ export PERL5OPT=-MDevel::SearchINC=/my/dev/dir
$ perl -MMy::Brand::New::Module -e'print "hello world\n"'
This is because PERL5OPT
options are processed after the actual command line options.
Also, the PERL5OPT
variable is ignored when Taint checks are enabled.
FUNCTIONS
build_cache
Called during import()
, this subroutine builds a cache of the modules it finds. This way every time a module is use()
d, we can just look at the cache. This does mean that if you add, change or delete a module during the run-time of a script that uses Devel::SearchINC
, that script won't notice these changes. If necessary, you could re-run build_cache()
.
MULTIPLE DEVELOPMENT DIRECTORIES
You can have multiple development directories. Just list them when using this module:
use Devel::SearchINC qw(/my/first/dir my/second/dir);
or
perl -MDevel::SearchINC=/my/first/dir,/my/second/dir
You can also use semicolons or colons instead of commas as delimiters for directories.
perlrun
details the syntax for specifying multiple arguments for modules brought in with the -M
switch.
SPECIAL OPTIONS
In addition to development directories, there are special options that can be passed to this module:
-debug
-
This turns on debugging; see below.
-clear
-
This option clears all paths that were previously set. This is useful when you have a
PERL5OPT
environment variable but want to use this module from within your code as well and want to override the environment setting. For example:export PERL5OPT=-MDevel::SearchINC=/path/to/dev
then:
#!/usr/bin/env perl use warnings; use strict; use Devel::SearchINC qw(-clear /path/to/other/dir); ...
DEBUGGING THIS MODULE
By using -debug
as one of the development directories, you can turn on debugging. Note that despite the leading colon, this has nothing to do with Exporter
semantics. With debugging activated, this module will print detailed information while trying to find the requested file.
For example
use Devel::SearchINC qw(/my/first/dir my/second/dir -debug);
or
perl -MDevel::SearchINC=/my/first/dir,-debug,/my/second/dir
The -debug
option can be specified anywhere in the list of development directories.
INSTALLATION
See perlmodinstall for information and options on installing Perl modules.
BUGS AND LIMITATIONS
No bugs have been reported.
Please report any bugs or feature requests through the web interface at http://rt.cpan.org/Public/Dist/Display.html?Name=Devel-SearchINC.
AVAILABILITY
The latest version of this module is available from the Comprehensive Perl Archive Network (CPAN). Visit http://www.perl.com/CPAN/ to find a CPAN site near you, or see http://search.cpan.org/dist/Devel-SearchINC/.
The development version lives at http://github.com/hanekomu/Devel-SearchINC.git and may be cloned from git://github.com/hanekomu/Devel-SearchINC.git. Instead of sending patches, please fork this project using the standard git and github infrastructure.
AUTHOR
Marcel Gruenauer <marcel@cpan.org>
COPYRIGHT AND LICENSE
This software is copyright (c) 2004 by Marcel Gruenauer.
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.