App::Info::Lib::Expat - Information about the Expat XML parser 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"; } 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.

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 returned by the "search_lib_dirs()" method for one of the files returned by the "search_lib_names()" method. If any of is found, then Expat is assumed to be installed. Otherwise, most of the object methods will return "undef". Events: Searching for Expat libraries Path to Expat library directory? 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: Searching for 'expat.h' Searching for include directory Cannot find include directory Cannot find 'expat.h' Failed to parse version from 'expat.h' 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: Searching for 'expat.h' Searching for include directory Cannot find include directory Cannot find 'expat.h' Failed to parse version from 'expat.h' 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: Searching for 'expat.h' Searching for include directory Cannot find include directory Cannot find 'expat.h' Failed to parse version from 'expat.h' 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: Searching for 'expat.h' Searching for include directory Cannot find include directory Cannot find 'expat.h' Failed to parse version from 'expat.h' 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. executable my $executable = $expat->executable; Since Expat includes no executable program, 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: Events: Searching for include directory Cannot find include directory 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: Events: Searching for shared object library directory Cannot find shared object library direcory 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. search_lib_names my @seach_lib_names = $self->search_lib_nams Returns a list of possible names for library files. Used by "lib_dir()" to search for library files. By default, the list is: search_so_lib_names my @seach_so_lib_names = $self->search_so_lib_nams Returns a list of possible names for shared object library files. Used by "so_lib_dir()" to search for library files. By default, the list is: search_lib_dirs my @search_lib_dirs = $expat->search_lib_dirs; Returns a list of possible directories in which to search for libraries. By default, it returns 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). search_inc_names my @search_inc_names = $expat->search_inc_names; Returns a list of include file names to search for. Used by "inc_dir()" to search for an include file. By default, the only name returned is expat.h. search_inc_dirs my @search_inc_dirs = $expat->search_inc_dirs; Returns a list of possible directories in which to search for include files. Used by "inc_dir()" to search for an include file. By default, the directories are: 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. Please send bug reports to <bug-app-info@rt.cpan.org> or file them at <http://rt.cpan.org/NoAuth/Bugs.html?Dist=App-Info>. David Wheeler <david@justatheory.com> based on code by Sam Tregar <sam@tregar.com> that Sam, in turn, borrowed from Clark Cooper's XML::Parser module. 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 (c) 2002-2004, 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.