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 meta data.

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.

  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:

info

Searching for Expat libraries

confirm

Path to Expat library directory?

unknown

Path to Expat library directory?

  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".

  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.

  my $name = $expat->name;

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

Returns the full version number for Expat. App::Info::Lib::Expat attempts 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

  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

  my $minor_version = $expat->minor_version;

Returns the Expat minor 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 "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

  my $patch_version = $expat->patch_version;

Returns the Expat patch version number. App::Info::Lib::Expat attempts 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

  my $bin_dir = $expat->bin_dir;

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

  my $executable = $expat->executable;

Since Expat includes no executable program, this method always returns false.

  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

  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" (new) constructor, as are the events.

  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 (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 directory

unknown

Enter a valid Expat shared object library directory

  my $home_url = $expat->home_url;

Returns the libexpat home page URL.

  my $download_url = $expat->download_url;

Returns the libexpat download URL.

  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:

libexpat.a

libexpat.la

libexpat.so

libexpat.so.0

libexpat.so.0.0.1

libexpat.dylib

libexpat.0.dylib

libexpat.0.0.1.dylib

  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:

libexpat.so

libexpat.so.0

libexpat.so.0.0.1

libexpat.dylib

libexpat.0.dylib

libexpat.0.0.1.dylib

  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 (Config) module -- plus /sw/lib (in support of all you Fink users out there).

  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.

  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:

/usr/local/include

/usr/include

/sw/include

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.

This module is stored in an open GitHub repository. Feel free to fork and contribute!

Please file bug reports via GitHub Issues or by sending mail to bug-App-Info@rt.cpan.org.

David E. 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 (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) 2002-2011, David E. Wheeler. Some Rights Reserved.

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