NAME

       Glib::Error -  Exception Objects based on GError

SYNOPSIS

         eval {
            my $pixbuf = Gtk2::Gdk::Pixbuf->new_from_file ($filename);
            $image->set_from_pixbuf ($pixbuf);
         };
         if ($@) {
            print "$@\n";
            if (Glib::Error::matches ($@, 'Gtk2::Gdk::Pixbuf::Error',
                                          'unknown-format')) {
               change_format_and_try_again ();
            } elsif (Glib::Error::matches ($@, 'Glib::File::Error', 'noent')) {
               change_source_dir_and_try_again ();
            } else {
               # don't know how to handle this
               die $@;
            }
         }

DESCRIPTION

       Gtk2-Perl translates GLib's GError runtime errors into Perl exceptions, by creating
       exception objects based on Glib::Error.  Glib::Error overloads the stringification
       operator, so a Glib::Error object will act like a string if used with print() or warn(),
       so most code using $@ will not even know the difference.

       The point of having exception objects, however, is that the error messages in GErrors are
       often localized with NLS translation.  Thus, it's not good for your code to attempt to
       handle errors by string matching on the the error message.  Glib::Error provides a way to
       get to the deterministic error code.

       You will typically deal with objects that inherit from Glib::Error, such as
       Glib::Convert::Error, Glib::File::Error, Gtk2::Gdk::Pixbuf::Error, etc; these classes are
       provided by the libraries that define the error domains.  However, it is possible to get a
       base Glib::Error when the bindings encounter an unknown or unbound error domain.  The
       interface used here degrades nicely in such a situation, but in general you should submit
       a bug report to the binding maintainer if you get such an exception.

HIERARCHY

         Glib::Boxed
         +----Glib::Error

METHODS

   scalar = Glib::Error::new ($class, $code, $message)
   scalar = $class->new ($code, $message)
       •   $code (Glib::Enum) an enumeration value, depends on $class

       •   $message (string)

       Create a new exception object of type $class, where $class is associated with a GError
       domain.  $code should be a value from the enumeration type associated with this error
       domain.  $message can be anything you like, but should explain what happened from the
       point of view of a user.

   integer = $error->code
       This is the numeric error code.  Normally, you'll want to use "value" instead, for
       readability.

   string = $error->domain
       The error domain.  You normally do not need this, as the object will be blessed into a
       corresponding class.

   string = $error->location
       The source line and file closest to the emission of the exception, in the same format that
       you'd get from croak() or die().

       If there's non-ascii characters in the filename Perl leaves them as raw bytes, so you may
       have to put the string through Glib::filename_display_name for a wide-char form.

   boolean = $error->matches ($domain, $code)
       •   $domain (string)

       •   $code (scalar)

       Returns true if the exception in $error matches the given $domain and $code.  $domain may
       be a class name or domain quark (that is, the real string used in C).  $code may be an
       integer value or an enum nickname; the enum type depends on the value of $domain.

   string = $error->message
       The error message.  This may be localized, as it is intended to be shown to a user.

   Glib::Error::register ($package, $enum_package)
       •   $package (string) class name to register as a Glib::Error.

       •   $enum_package (string) class name of the enum type to use for this domain's error
           codes.

       Register a new error domain.  Glib::Error will be added @package::ISA for you.
       enum_package must be a valid Glib::Enum type, either from a C library or registered with
       "Glib::Type::register_enum".  After registering an error domain, you can create or throw
       exceptions of this type.

   scalar = Glib::Error::throw ($class, $code, $message)
   scalar = $class->throw ($code, $message)
       •   $code (Glib::Enum) an enumeration value, depends on $class

       •   $message (string)

       Throw an exception with a Glib::Error exception object.  Equivalent to "croak
       (Glib::Error::new ($class, $code, $message));".

   string = $error->value
       The enumeration value nickname of the integer value in "$error->code", according to this
       error domain.  This will not be available if the error object is a base Glib::Error,
       because the bindings will have no idea how to get to the correct nickname.

SEE ALSO

       Glib, Glib::Boxed

COPYRIGHT

       Copyright (C) 2003-2011 by the gtk2-perl team.

       This software is licensed under the LGPL.  See Glib for a full notice.