1XML::LibXML::Error(3) User Contributed Perl DocumentationXML::LibXML::Error(3)
2
6 XML::LibXML::Error - Structured Errors
7
9 eval { ... };
10 if (ref($@)) {
11 # handle a structured error (XML::LibXML::Error object)
12 } elsif ($@) {
13 # error, but not an XML::LibXML::Error object
14 } else {
15 # no error
16 }
17 $XML::LibXML::Error::WARNINGS=1;
19 $message = $@->as_string();
20 print $@->dump();
21 $error_domain = $@->domain();
22 $error_code = $@->code();
23 $error_message = $@->message();
24 $error_level = $@->level();
25 $filename = $@->file();
26 $line = $@->line();
27 $nodename = $@->nodename();
28 $error_str1 = $@->str1();
29 $error_str2 = $@->str2();
30 $error_str3 = $@->str3();
31 $error_num1 = $@->num1();
32 $error_num2 = $@->num2();
33 $string = $@->context();
34 $offset = $@->column();
35 $previous_error = $@->_prev();
36
38 The XML::LibXML::Error class is a tiny frontend to libxml2's structured
39 error support. If XML::LibXML is compiled with structured error
40 support, all errors reported by libxml2 are transformed to
41 XML::LibXML::Error objects. These objects automatically serialize to
42 the corresponding error messages when printed or used in a string
43 operation, but as objects, can also be used to get a detailed and
44 structured information about the error that occurred.
45 Unlike most other XML::LibXML objects, XML::LibXML::Error doesn't wrap
47 an underlying libxml2 structure directly, but rather transforms it to a
48 blessed Perl hash reference containing the individual fields of the
49 structured error information as hash key-value pairs. Individual items
50 (fields) of a structured error can either be obtained directly as
51 $@->{field}, or using autoloaded methods such as $@->field() (where
52 field is the field name). XML::LibXML::Error objects have the following
53 fields: domain, code, level, file, line, nodename, message, str1, str2,
54 str3, num1, num2, and _prev (some of them may be undefined).
55 $XML::LibXML::Error::WARNINGS
57 $XML::LibXML::Error::WARNINGS=1;
58 Traditionally, XML::LibXML was suppressing parser warnings by
60 setting libxml2's global variable xmlGetWarningsDefaultValue to 0.
61 Since 1.70 we do not change libxml2's global variables anymore; for
62 backward compatibility, XML::LibXML suppresses warnings. This
63 variable can be set to 1 to enable reporting of these warnings via
64 Perl "warn" and to 2 to report hem via "die".
65 as_string
67 $message = $@->as_string();
68 This function serializes an XML::LibXML::Error object to a string
70 containing the full error message close to the message produced by
71 libxml2 default error handlers and tools like xmllint. This method
72 is also used to overload "" operator on XML::LibXML::Error, so it
73 is automatically called whenever XML::LibXML::Error object is
74 treated as a string (e.g. in print $@).
75 dump
77 print $@->dump();
78 This function serializes an XML::LibXML::Error to a string
80 displaying all fields of the error structure individually on
81 separate lines of the form 'name' => 'value'.
82 domain
84 $error_domain = $@->domain();
85 Returns string containing information about what part of the
87 library raised the error. Can be one of: "parser", "tree",
88 "namespace", "validity", "HTML parser", "memory", "output", "I/O",
89 "ftp", "http", "XInclude", "XPath", "xpointer", "regexp", "Schemas
90 datatype", "Schemas parser", "Schemas validity", "Relax-NG parser",
91 "Relax-NG validity", "Catalog", "C14N", "XSLT", "validity".
92 code
94 $error_code = $@->code();
95 Returns the actual libxml2 error code. The XML::LibXML::ErrNo
97 module defines constants for individual error codes. Currently
98 libxml2 uses over 480 different error codes.
99 message
101 $error_message = $@->message();
102 Returns a human-readable informative error message.
104 level
106 $error_level = $@->level();
107 Returns an integer value describing how consequent is the error.
109 XML::LibXML::Error defines the following constants:
110 · XML_ERR_NONE = 0
112 · XML_ERR_WARNING = 1 : A simple warning.
114 · XML_ERR_ERROR = 2 : A recoverable error.
116 · XML_ERR_FATAL = 3 : A fatal error.
118 file
120 $filename = $@->file();
121 Returns the filename of the file being processed while the error
123 occurred.
124 line
126 $line = $@->line();
127 The line number, if available.
129 nodename
131 $nodename = $@->nodename();
132 Name of the node where error occurred, if available. When this
134 field is non-empty, libxml2 actually returned a physical pointer to
135 the specified node. Due to memory management issues, it is very
136 difficult to implement a way to expose the pointer to the Perl
137 level as a XML::LibXML::Node. For this reason, XML::LibXML::Error
138 currently only exposes the name the node.
139 str1
141 $error_str1 = $@->str1();
142 Error specific. Extra string information.
144 str2
146 $error_str2 = $@->str2();
147 Error specific. Extra string information.
149 str3
151 $error_str3 = $@->str3();
152 Error specific. Extra string information.
154 num1
156 $error_num1 = $@->num1();
157 Error specific. Extra numeric information.
159 num2
161 $error_num2 = $@->num2();
162 In recent libxml2 versions, this value contains a column number of
164 the error or 0 if N/A.
165 context
167 $string = $@->context();
168 For parsing errors, this field contains about 80 characters of the
170 XML near the place where the error occurred. The field
171 "$@->column()" contains the corresponding offset. Where N/A, the
172 field is undefined.
173 column
175 $offset = $@->column();
176 See "$@->column()" above.
178 _prev
180 $previous_error = $@->_prev();
181 This field can possibly hold a reference to another
183 XML::LibXML::Error object representing an error which occurred just
184 before this error.
185
187 Matt Sergeant, Christian Glahn, Petr Pajas
188
190 2.0132
191
193 2001-2007, AxKit.com Ltd.
194 2002-2006, Christian Glahn.
196 2006-2009, Petr Pajas.
198
200 This program is free software; you can redistribute it and/or modify it
201 under the same terms as Perl itself.
202perl v5.28.0 2017-10-28 XML::LibXML::Error(3)