Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help
General::Extended(3)  User Contributed Perl Documentation General::Extended(3)

NAME
       Config::General::Extended - Extended access to Config files

SYNOPSIS
	use Config::General;

	$conf =	Config::General->new(
	   -ConfigFile	   => 'configfile',
	   -ExtendedAccess => 1
	);

DESCRIPTION
       This is an internal module which	makes it possible to use object
       oriented	methods	to access parts	of your	config file.

       Normally	you don't call it directly.

METHODS
       configfile('filename')
	   Set the filename to be used by save to "filename". It returns the
	   current configured filename if called without arguments.

       obj('key')
	   Returns a new object	(of Config::General::Extended Class) from the
	   given key.  Short example: Assume you have the following config:

	    <individual>
		 <martin>
		    age	  23
		 </martin>
		 <joseph>
		    age	  56
		 </joseph>
	    </individual>
	    <other>
		 blah	  blubber
		 blah	  gobble
		 leer
	    </other>

	   and already read it in using	Config::General::Extended::new(), then
	   you can get a new object from the "individual" block	this way:

	    $individual	= $conf->obj("individual");

	   Now if you call getall on $individual (just for reference) you
	   would get:

	    $VAR1 = (
	       martin => { age => 13 }
		    );

	   Or, here is another use:

	    my $individual = $conf->obj("individual");
	    foreach my $person ($conf->keys("individual")) {
	       $man = $individual->obj($person);
	       print "$person is " . $man->value("age")	. " years old\n";
	    }

	   See the discussion on hash()	and value() below.

	   If the key from which you want to create a new object is empty, an
	   empty object	will be	returned. If you run the following on the
	   above config:

	    $obj = $conf->obj("other")->obj("leer");

	   Then	$obj will be empty, just like if you have had run this:

	    $obj = Config::General::Extended->new( () );

	   Read	operations on this empty object	will return nothing or even
	   fail.  But you can use an empty object for creating a new config
	   using write operations, i.e.:

	    $obj->someoption("value");

	   See the discussion on AUTOLOAD METHODS below.

	   If the key points to	a list of hashes, a list of objects will be
	   returned. Given the following example config:

	    <option>
	      name = max
	    </option>
	    <option>
	      name = bea
	    </option>

	   you could write code	like this to access the	list the OOP way:

	    my $objlist	= $conf->obj("option");
	    foreach my $option (@{$objlist}) {
	     print $option->name;
	    }

	   Please note that the	list will be returned as a reference to	an
	   array.

	   Empty elements or non-hash elements of the list, if any, will be
	   skipped.

       hash('key')
	   This	method returns a hash(if it is one!) from the config which is
	   referenced by "key".	Given the sample config	above you would	get:

	    my %sub_hash = $conf->hash("individual");
	    print Dumper(\%sub_hash);
	    $VAR1 = {
	       martin => { age => 13 }
		    };

       array('key')
	   This	the equivalent of hash() mentioned above, except that it
	   returns an array.  Again, we	use the	sample config mentioned	above:

	    $other = $conf->obj("other");
	    my @blahs =	$other->array("blah");
	    print Dumper(\@blahs);
	    $VAR1 = [ "blubber", "gobble" ];

       value('key')
	   This	method returns the scalar value	of a given key.	Given the
	   following sample config:

	    name  = arthur
	    age	  = 23

	   you could do	something like that:

	    print $conf->value("name") . " is "	. $conf->value("age") .	" years	old\n";

	   You can use this method also	to set the value of "key" to something
	   if you give over a hash reference, array reference or a scalar in
	   addition to the key.	An example:

	    $conf->value("key",	\%somehash);
	    # or
	    $conf->value("key",	\@somearray);
	    # or
	    $conf->value("key",	$somescalar);

	   Please note,	that this method does not complain about existing
	   values within "key"!

       is_hash('key') is_array('key') is_scalar('key')
	   As seen above, you can access parts of your current config using
	   hash, array or scalar methods. But you are right if you guess, that
	   this	might become problematic, if for example you call hash() on a
	   key which is	in real	not a hash but a scalar. Under normal
	   circumstances perl would refuse this	and die.

	   To avoid such behavior you can use one of the methods is_hash()
	   is_array() is_scalar() to check if the value	of "key" is really
	   what	you expect it to be.

	   An example(based on the config example from above):

	    if($conf->is_hash("individual") {
	       $individual = $conf->obj("individual");
	    }
	    else {
	       die "You	need to	configure a "individual" block!\n";
	    }

       exists('key')
	   This	method returns just true if the	given key exists in the
	   config.

       keys('key')
	   Returns an array of the keys	under the specified "key". If you use
	   the example config above you	could do that:

	    print Dumper($conf->keys("individual");
	    $VAR1 = [ "martin",	"joseph" ];

	   If no key name was supplied,	then the keys of the object itself
	   will	be returned.

	   You can use this method in foreach loops as seen in an example
	   above(obj() ).

       delete('key')
	   This	method removes the given key and all associated	data from the
	   internal hash structure. If 'key' contained data, then this data
	   will	be returned, otherwise undef will be returned.

       find(@list)
	   Given a list	of nodes, ->find will search for a tree	that branches
	   in just this	way, returning the Config::General::Extended object it
	   finds at the	bottom if it exists.  You can also search partway down
	   the tree and	->find should return where you left off.

	   For example,	given the values find (qw (A B C)) and the following
	   tree	(</end>	tags omitted for brevity):

	    <A>
		   <FOO>
			   ...
		   <B>
			   <BAZ>
				   ...
			   <C>
				   BAR = shoo

	   find() will find the	object at C with the value BAR = shoo and
	   return it.

AUTOLOAD METHODS
       Another useful feature is implemented in	this class using the AUTOLOAD
       feature of perl.	If you know the	keynames of a block within your
       config, you can access to the values of each individual key using the
       method notation.	See the	following example and you will get it:

       We assume the following config:

	<person>
	   name	   = Moser
	   prename = Peter
	   birth   = 12.10.1972
	</person>

       Now we read it in and process it:

	my $conf = Config::General::Extended->new("configfile");
	my $person = $conf->obj("person");
	print $person->prename . " " . $person->name . " is " .	$person->age . " years old\n";

       This notation supports only scalar values! You need to make sure, that
       the block <person> does not contain any subblock	or multiple identical
       options(which will become an array after	parsing)!

       If you access a non-existent key	this way, Config::General will croak
       an error.  You can turn this behavior off by setting -StrictObjects to
       0 or "no". In this case undef will be returned.

       Of course you can use this kind of methods for writing data too:

	$person->name("Neustein");

       This changes the	value of the "name" key	to "Neustein". This feature
       behaves exactly like value(), which means you can assign	hash or	array
       references as well and that existing values under the given key will be
       overwritten.

COPYRIGHT
       Copyright (c) 2000-2014 Thomas Linden

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

BUGS
       none known yet.

AUTHOR
       Thomas Linden <tlinden |AT| cpan.org>

VERSION
       2.07

perl v5.24.1			  2015-10-22		  General::Extended(3)

NAME | SYNOPSIS | DESCRIPTION | METHODS | AUTOLOAD METHODS | COPYRIGHT | BUGS | AUTHOR | VERSION

Want to link to this manual page? Use this URL:
<https://www.freebsd.org/cgi/man.cgi?query=Config::General::Extended&sektion=3&manpath=FreeBSD+12.1-RELEASE+and+Ports>

home | help