/ 
App-Info-0.23
River stage one • 1 direct dependent • 2 total dependents
/ App::Info::Lib::Expat

NAME

App::Info::Lib::Expat - Information about the Expat XML parser

SYNOPSIS

use App::Info::Lib::Expat;

my $expat = App::Info::Lib::Expat->new;

if ($expat->installed) {
    print "App name: ", $expat->name, "\n";
    print "Version:  ", $expat->version, "\n";
    print "Bin dir:  ", $expat->bin_dir, "\n";
} else {
    print "Expat is not installed. :-(\n";
}

DESCRIPTION

App::Info::Lib::Expat supplies information about the Expat XML parser installed on the local system. It implements all of the methods defined by App::Info::Lib. Methods that trigger events will trigger them only the first time they're called (See App::Info for documentation on handling events). To start over (after, say, someone has installed Expat) construct a new App::Info::Lib::Expat object to aggregate new metadata.

Some of the methods trigger the same events. This is due to cross-calling of shared subroutines. However, any one event should be triggered no more than once. For example, although the info event "Searching for 'expat.h'" is documented for the methods version(), major_version(), minor_version(), and patch_version(), rest assured that it will only be triggered once, by whichever of those four methods is called first.

INTERFACE

Constructor

new

my $expat = App::Info::Lib::Expat->new(@params);

Returns an App::Info::Lib::Expat object. See App::Info for a complete description of argument parameters.

When called, new() searches all of the paths in the libsdirs and loclibpth attributes defined by the Perl Config module -- plus /sw/lib (in support of all you Fink users out there) -- for one of the following files:

libexpat.so
libexpat.so.0
libexpat.so.0.0.1
libexpat.dylib
libexpat.0.dylib
libexpat.0.0.1.dylib
libexpat.a
libexpat.la

If any of these files is found, then Expat is assumed to be installed. Otherwise, most of the object methods will return undef.

Events:

info

Searching for Expat libraries

confirm

Path to Expat library directory?

unknown

Path to Expat library directory?

Class Method

key_name

my $key_name = App::Info::Lib::Expat->key_name;

Returns the unique key name that describes this class. The value returned is the string "Expat".

Object Methods

installed

print "Expat is ", ($expat->installed ? '' : 'not '),
  "installed.\n";

Returns true if Expat is installed, and false if it is not. App::Info::Lib::Expat determines whether Expat is installed based on the presence or absence on the file system of one of the files searched for when new() constructed the object. If Expat does not appear to be installed, then most of the other object methods will return empty values.

name

my $name = $expat->name;

Returns the name of the application. In this case, name() simply returns the string "Expat".

version

Returns the full version number for Expat. App::Info::Lib::Expat attempts to parse the version number from the expat.h file, if it exists.

Events:

info

Searching for 'expat.h'

Searching for include directory

error

Cannot find include directory

Cannot find 'expat.h'

Failed to parse version from 'expat.h'

unknown

Enter a valid Expat include directory

Enter a valid Expat version number

major_version

my $major_version = $expat->major_version;

Returns the Expat major version number. App::Info::Lib::Expat attempts to parse the version number from the expat.h file, if it exists. For example, if version() returns "1.95.2", then this method returns "1".

Events:

info

Searching for 'expat.h'

Searching for include directory

error

Cannot find include directory

Cannot find 'expat.h'

Failed to parse version from 'expat.h'

unknown

Enter a valid Expat include directory

Enter a valid Expat major version number

minor_version

my $minor_version = $expat->minor_version;

Returns the Expat minor version number. App::Info::Lib::Expat attempst to parse the version number from the expat.h file, if it exists. For example, if version() returns "1.95.2", then this method returns "95".

Events:

info

Searching for 'expat.h'

Searching for include directory

error

Cannot find include directory

Cannot find 'expat.h'

Failed to parse version from 'expat.h'

unknown

Enter a valid Expat include directory

Enter a valid Expat minor version number

patch_version

my $patch_version = $expat->patch_version;

Returns the Expat patch version number. App::Info::Lib::Expat attempst to parse the version number from the expat.h file, if it exists. For example, version() returns "1.95.2", then this method returns "2".

Events:

info

Searching for 'expat.h'

Searching for include directory

error

Cannot find include directory

Cannot find 'expat.h'

Failed to parse version from 'expat.h'

unknown

Enter a valid Expat include directory

Enter a valid Expat patch version number

bin_dir

my $bin_dir = $expat->bin_dir;

Since Expat includes no binaries, this method always returns false.

inc_dir

my $inc_dir = $expat->inc_dir;

Returns the directory path in which the file expat.h was found. App::Info::Lib::Expat searches for expat.h in the following directories:

/usr/local/include
/usr/include
/sw/include

Events:

info

Searching for include directory

error

Cannot find include directory

unknown

Enter a valid Expat include directory

lib_dir

my $lib_dir = $expat->lib_dir;

Returns the directory path in which a Expat library was found. The files and paths searched are as described for the "new" constructor, as are the events.

so_lib_dir

my $so_lib_dir = $expat->so_lib_dir;

Returns the directory path in which a Expat shared object library was found. It searches all of the paths in the libsdirs and loclibpth attributes defined by the Perl Config module -- plus /sw/lib (for all you Fink fans) -- for one of the following files:

libexpat.so
libexpat.so.0
libexpat.so.0.0.1
libexpat.dylib
libexpat.0.dylib
libexpat.0.0.1.dylib

Events:

info

Searching for shared object library directory

error

Cannot find shared object library direcory

unknown

Enter a valid Expat shared object library directory

home_url

my $home_url = $expat->home_url;

Returns the libexpat home page URL.

download_url

my $download_url = $expat->download_url;

Returns the libexpat download URL.

KNOWN ISSUES

This is a pretty simple class. It's possible that there are more directories that ought to be searched for libraries and includes. And if anyone knows how to get the version numbers, let me know!

The format of the version number seems to have changed recently (1.95.1-2), and now I don't know where to find the version number. Patches welcome.

BUGS

Report all bugs via the CPAN Request Tracker at http://rt.cpan.org/NoAuth/Bugs.html?Dist=App-Info.

AUTHOR

David Wheeler <david@wheeler.net> based on code by Sam Tregar <sam@tregar.com> that Sam, in turn, borrowed from Clark Cooper's XML::Parser module.

SEE ALSO

App::Info documents the event handling interface.

App::Info::Lib is the App::Info::Lib::Expat parent class.

XML::Parser uses Expat to parse XML.

Config provides Perl configure-time information used by App::Info::Lib::Expat to locate Expat libraries and files.

http://expat.sourceforge.net/ is the Expat home page.

COPYRIGHT AND LICENSE

Copyright (c) 2002, David Wheeler. All Rights Reserved.

This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.