1Glib::Error(3) User Contributed Perl Documentation Glib::Error(3)
2
6 Glib::Error - Exception Objects based on GError
7
9 eval {
10 my $pixbuf = Gtk2::Gdk::Pixbuf->new_from_file ($filename);
11 $image->set_from_pixbuf ($pixbuf);
12 };
13 if ($@) {
14 print "$@\n";
15 if (Glib::Error::matches ($@, 'Gtk2::Gdk::Pixbuf::Error',
16 'unknown-format')) {
17 change_format_and_try_again ();
18 } elsif (Glib::Error::matches ($@, 'Glib::File::Error', 'noent')) {
19 change_source_dir_and_try_again ();
20 } else {
21 # don't know how to handle this
22 die $@;
23 }
24 }
25
27 Gtk2-Perl translates GLib's GError runtime errors into Perl exceptions,
28 by creating exception objects based on Glib::Error. Glib::Error
29 overloads the stringification operator, so a Glib::Error object will
30 act like a string if used with print() or warn(), so most code using $@
31 will not even know the difference.
32 The point of having exception objects, however, is that the error
34 messages in GErrors are often localized with NLS translation. Thus,
35 it's not good for your code to attempt to handle errors by string
36 matching on the the error message. Glib::Error provides a way to get
37 to the deterministic error code.
38 You will typically deal with objects that inherit from Glib::Error,
40 such as Glib::Convert::Error, Glib::File::Error,
41 Gtk2::Gdk::Pixbuf::Error, etc; these classes are provided by the
42 libraries that define the error domains. However, it is possible to
43 get a base Glib::Error when the bindings encounter an unknown or
44 unbound error domain. The interface used here degrades nicely in such
45 a situation, but in general you should submit a bug report to the
46 binding maintainer if you get such an exception.
47
49 Glib::Boxed
50 +----Glib::Error
51
53 scalar = Glib::Error::new ($class, $code, $message)
54 scalar = $class->new ($code, $message)
55 · $code (Glib::Enum) an enumeration value, depends on $class
56 · $message (string)
58 Create a new exception object of type $class, where $class is
60 associated with a GError domain. $code should be a value from the
61 enumeration type associated with this error domain. $message can be
62 anything you like, but should explain what happened from the point of
63 view of a user.
64 integer = $error->code
66 This is the numeric error code. Normally, you'll want to use "value"
67 instead, for readability.
68 string = $error->domain
70 The error domain. You normally do not need this, as the object will be
71 blessed into a corresponding class.
72 string = $error->location
74 The source line and file closest to the emission of the exception, in
75 the same format that you'd get from croak() or die().
76 If there's non-ascii characters in the filename Perl leaves them as raw
78 bytes, so you may have to put the string through
79 Glib::filename_display_name for a wide-char form.
80 boolean = $error->matches ($domain, $code)
82 · $domain (string)
83 · $code (scalar)
85 Returns true if the exception in $error matches the given $domain and
87 $code. $domain may be a class name or domain quark (that is, the real
88 string used in C). $code may be an integer value or an enum nickname;
89 the enum type depends on the value of $domain.
90 string = $error->message
92 The error message. This may be localized, as it is intended to be
93 shown to a user.
94 Glib::Error::register ($package, $enum_package)
96 · $package (string) class name to register as a Glib::Error.
97 · $enum_package (string) class name of the enum type to use for this
99 domain's error codes.
100 Register a new error domain. Glib::Error will be added @package::ISA
102 for you. enum_package must be a valid Glib::Enum type, either from a C
103 library or registered with "Glib::Type::register_enum". After
104 registering an error domain, you can create or throw exceptions of this
105 type.
106 scalar = Glib::Error::throw ($class, $code, $message)
108 scalar = $class->throw ($code, $message)
109 · $code (Glib::Enum) an enumeration value, depends on $class
110 · $message (string)
112 Throw an exception with a Glib::Error exception object. Equivalent to
114 "croak (Glib::Error::new ($class, $code, $message));".
115 string = $error->value
117 The enumeration value nickname of the integer value in "$error->code",
118 according to this error domain. This will not be available if the
119 error object is a base Glib::Error, because the bindings will have no
120 idea how to get to the correct nickname.
121
123 Glib, Glib::Boxed
124
126 Copyright (C) 2003-2011 by the gtk2-perl team.
127 This software is licensed under the LGPL. See Glib for a full notice.
129perl v5.28.0 2018-10-04 Glib::Error(3)