Provided by: libmodule-info-perl_0.37-1_all 
NAME
Module::Info - Information about Perl modules
SYNOPSIS
use Module::Info;
my $mod = Module::Info->new_from_file('Some/Module.pm');
my $mod = Module::Info->new_from_module('Some::Module');
my $mod = Module::Info->new_from_loaded('Some::Module');
my @mods = Module::Info->all_installed('Some::Module');
my $name = $mod->name;
my $version = $mod->version;
my $dir = $mod->inc_dir;
my $file = $mod->file;
my $is_core = $mod->is_core;
# Only available in perl 5.6.1 and up.
# These do compile the module.
my @packages = $mod->packages_inside;
my @used = $mod->modules_used;
my @subs = $mod->subroutines;
my @isa = $mod->superclasses;
my @calls = $mod->subroutines_called;
# Check for constructs which make perl hard to predict.
my @methods = $mod->dynamic_method_calls;
my @lines = $mod->eval_string; *UNIMPLEMENTED*
my @lines = $mod->gotos; *UNIMPLEMENTED*
my @controls = $mod->exit_via_loop_control; *UNIMPLEMENTED*
my @unpredictables = $mod->has_unpredictables; *UNIMPLEMENTED*
# set/get Module::Info options
$self->die_on_compilation_error(1);
my $die_on_error = $mod->die_on_compilation_error;
$self->safe(1);
my $safe = $mod->safe;
DESCRIPTION
Module::Info gives you information about Perl modules without actually loading the module.
It actually isn't specific to modules and should work on any perl code.
METHODS
Constructors
There are a few ways to specify which module you want information for. They all return
Module::Info objects.
new_from_file
my $module = Module::Info->new_from_file('path/to/Some/Module.pm');
Given a file, it will interpret this as the module you want information about. You
can also hand it a perl script.
If the file doesn't exist or isn't readable it will return false.
new_from_module
my $module = Module::Info->new_from_module('Some::Module');
my $module = Module::Info->new_from_module('Some::Module', @INC);
Given a module name, @INC will be searched and the first module found used. This is
the same module that would be loaded if you just say "use Some::Module".
If you give your own @INC, that will be used to search instead.
new_from_loaded
my $module = Module::Info->new_from_loaded('Some::Module');
Gets information about the currently loaded version of Some::Module. If it isn't
loaded, returns false.
all_installed
my @modules = Module::Info->all_installed('Some::Module');
my @modules = Module::Info->all_installed('Some::Module', @INC);
Like new_from_module(), except all modules in @INC will be returned, in the order they
are found. Thus $modules[0] is the one that would be loaded by "use Some::Module".
Information without loading
The following methods get their information without actually compiling the module.
name
my $name = $module->name;
$module->name($name);
Name of the module (ie. Some::Module).
Module loaded using new_from_file() won't have this information in which case you can
set it yourself.
version
my $version = $module->version;
Divines the value of $VERSION. This uses the same method as ExtUtils::MakeMaker and
all caveats therein apply.
inc_dir
my $dir = $module->inc_dir;
Include directory in which this module was found. Module::Info objects created with
new_from_file() won't have this info.
file
my $file = $module->file;
The absolute path to this module.
is_core
my $is_core = $module->is_core;
Checks if this module is the one distributed with Perl.
NOTE This goes by what directory it's in. It's possible that the module has been
altered or upgraded from CPAN since the original Perl installation.
has_pod
my $has_pod = $module->has_pod;
Returns the location of the module's pod, which can be the module file itself, if the
POD is inlined, the associated POD file, or nothing if there is no POD at all.
Information that requires loading.
WARNING! From here down reliability drops rapidly!
The following methods get their information by compiling the module and examining the
opcode tree. The module will be compiled in a separate process so as not to disturb the
current program.
They will only work on 5.6.1 and up and requires the B::Utils module.
packages_inside
my @packages = $module->packages_inside;
Looks for any explicit "package" declarations inside the module and returns a list.
Useful for finding hidden classes and functionality (like Tie::StdHandle inside
Tie::Handle).
KNOWN BUG Currently doesn't spot package changes inside subroutines.
package_versions
my %versions = $module->package_versions;
Returns a hash whose keys are the packages contained in the module (these are the same
as what's returned by "packages_inside()"), and whose values are the versions of those
packages.
modules_used
my @used = $module->modules_used;
Returns a list of all modules and files which may be "use"'d or "require"'d by this
module.
NOTE These modules may be conditionally loaded, can't tell. Also can't find modules
which might be used inside an "eval".
modules_required
my %required = $module->modules_required;
Returns a list of all modules and files which may be "use"'d or "require"'d by this
module, together with the minimum required version.
The hash is keyed on the module/file name, the corrisponding value is an array
reference containing the requied versions, or an empty array if no specific version
was required.
NOTE These modules may be conditionally loaded, can't tell. Also can't find modules
which might be used inside an "eval".
subroutines
my %subs = $module->subroutines;
Returns a hash of all subroutines defined inside this module and some info about it.
The key is the *full* name of the subroutine (ie. $subs{'Some::Module::foo'} rather
than just $subs{'foo'}), value is a hash ref with information about the subroutine
like so:
start => line number of the first statement in the subroutine
end => line number of the last statement in the subroutine
Note that the line numbers may not be entirely accurate and will change as perl's
backend compiler improves. They typically correspond to the first and last run-time
statements in a subroutine. For example:
sub foo {
package Wibble;
$foo = "bar";
return $foo;
}
Taking "sub foo {" as line 1, Module::Info will report line 3 as the start and line 4
as the end. "package Wibble;" is a compile-time statement. Again, this will change
as perl changes.
Note this only catches simple "sub foo {...}" subroutine declarations. Anonymous,
autoloaded or eval'd subroutines are not listed.
superclasses
my @isa = $module->superclasses;
Returns the value of @ISA for this $module. Requires that $module->name be set to
work.
NOTE superclasses() is currently cheating. See CAVEATS below.
subroutines_called
my @calls = $module->subroutines_called;
Finds all the methods and functions which are called inside the $module.
Returns a list of hashes. Each hash represents a single function or method call and
has the keys:
line line number where this call originated
class class called on if its a class method
type function, symbolic function, object method,
class method, dynamic object method or
dynamic class method.
(NOTE This format will probably change)
name name of the function/method called if not dynamic
Information about Unpredictable Constructs
Unpredictable constructs are things that make a Perl program hard to predict what its
going to do without actually running it. There's nothing wrong with these constructs, but
its nice to know where they are when maintaining a piece of code.
dynamic_method_calls
my @methods = $module->dynamic_method_calls;
Returns a list of dynamic method calls (ie. "$obj-"$method()>) used by the $module.
@methods has the same format as the return value of subroutines_called().
Options
The following methods get/set specific option values for the Module::Info object.
die_on_compilation_error
$module->die_on_compilation_error(0); # default
$module->die_on_compilation_error(1);
my $flag = $module->die_on_compilation_error;
Sets/gets the "die on compilation error" flag. When the flag is off (default), and a
module fails to compile, Module::Info simply emits a watning and continues. When the
flag is on and a module fails to compile, Module::Info "die()"s with the same error
message it would use in the warning.
safe
$module->safe(0); # default
$module->safe(1); # be safer
my $flag = $module->safe;
Sets/gets the "safe" flag. When the flag is enabled all operations requiring module
compilation are forbidden and the "version()" method executes its code in a "Safe"
compartment.
use_version
$module->use_version(0); # do not use version.pm (default)
$module->use_version(1); # use version.pm, die if not present
my $flag = $module->use_version;
Sets/gets the "use_version" flag. When the flag is enabled the 'version' method always
returns a version object.
REPOSITORY
<https://github.com/neilb/Module-Info>
AUTHOR
Michael G Schwern <schwern@pobox.com> with code from ExtUtils::MM_Unix,
Module::InstalledVersion and lots of cargo-culting from B::Deparse.
Mattia Barbon <mbarbon@cpan.org> maintained the module from 2002 to 2013.
Neil Bowers <neilb@cpan.org> is the current maintainer.
LICENSE
This program is free software; you can redistribute it and/or modify it under the same
terms as Perl itself.
THANKS
Many thanks to Simon Cozens and Robin Houston for letting me chew their ears about B.
CAVEATS
Code refs in @INC are currently ignored. If this bothers you submit a patch.
superclasses() is cheating and just loading the module in a separate process and looking
at @ISA. I don't think its worth the trouble to go through and parse the opcode tree as
it still requires loading the module and running all the BEGIN blocks. Patches welcome.
I originally was going to call superclasses() isa() but then I remembered that would be
bad.
All the methods that require loading are really inefficient as they're not caching
anything. I'll worry about efficiency later.