Net::IDN::Encode(3pm)

1Net::IDN::Encode(3)   User Contributed Perl Documentation  Net::IDN::Encode(3)
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NAME

6       Net::IDN::Encode - Internationalizing Domain Names in Applications
7       (IDNA)
8

SYNOPSIS

10         use Net::IDN::Encode ':all';
11         my $a = domain_to_ascii("müller.example.org");
12         my $e = email_to_ascii("POSTMASTER@例。テスト");
13         my $u = domain_to_unicode('EXAMPLE.XN--11B5BS3A9AJ6G');
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DESCRIPTION

16       This module provides an easy-to-use interface for encoding and decoding
17       Internationalized Domain Names (IDNs).
18
19       IDNs use characters drawn from a large repertoire (Unicode), but IDNA
20       allows the non-ASCII characters to be represented using only the ASCII
21       characters already allowed in so-called host names today (letter-digit-
22       hyphen, "/[A-Z0-9-]/i").
23
24       Use this module if you just want to convert domain names (or email
25       addresses), using whatever IDNA standard is the best choice at the
26       moment.
27
28       You should be familiar with Unicode support in perl, as this module
29       expects correctly encoded input. See perlunitut, perluniintro and
30       perlunicode for details.
31

UNICODE VERSION

33       To convert labels correctly between Unicode and ASCII, each character
34       in the label must be present in the Unicode version supported by your
35       perl.  Consequently, this module will refuse to convert labels with new
36       Unicode characters on older perl versions (see below).
37

FUNCTIONS

39       By default, this module does not export any subroutines. You may use
40       the ":all" tag to import everything. You can also use regular
41       expressions such as "/^to_/" or "/^email_/" to select some of the
42       functions, see Exporter for details.
43
44       The following functions are available:
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46       to_ascii( $label, %param )
47           Converts a single label $label to ASCII. Will throw an exception on
48           invalid input. If $label is already a valid ASCII domain label
49           (including most NON-LDH labels such as those used for SRV records
50           and fake A-labels), this function will never fail but return $label
51           as-is if conversion would fail.
52
53           This function takes the following optional parameters (%param):
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55           AllowUnassigned
56               (boolean) If set to a true value, code points that are
57               unassigned in the Unicode version supported by your perl are
58               allowed. This is an extension over UTS #46.
59
60               While this increases the number of labels that can be converted
61               successfully (especially on older perls) and may thus maximizes
62               the compatibility with domain names created under future
63               versions of Unicode, it also introduces the risk of incorrect
64               conversions.  Characters added in later versions of Unicode
65               might have properties that affect the conversion; if these
66               properties are not known on your version of perl, you might
67               therefore end up with an incorrect conversion.
68
69               The default is false.
70
71           UseSTD3ASCIIRules
72               (boolean) If set to a true value, checks the label for
73               compliance with STD 3 (RFC 1123) syntax for host name parts.
74               The exact checks done depend on the IDNA standard used.
75               Usually, you will want to set this to true.
76
77               Please note that UseSTD3ASCIIRules only affects the conversion
78               between ASCII labels (A-labels) and Unicode labels (U-labels).
79               Labels that are in ASCII may still be passed-through as-is.
80
81               For historical reasons, the default is false (unlike
82               "domain_to_ascii").
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84           TransitionalProcessing
85               (boolean) If set to true, the conversion will be compatible
86               with IDNA2003. This only affects four characters: 'ß' (U+00DF),
87               'ς' (U+03C2), ZWJ (U+200D) and ZWNJ (U+200C). Usually, you will
88               want to set this to false.
89
90               The default is false.
91
92           This function does not handle strings that consist of multiple
93           labels (such as domain names). Use "domain_to_ascii" instead.
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95       to_unicode( $label, %param )
96           Converts a single label $label to Unicode. Will throw an exception
97           on invalid input. If $label is an ASCII label (including most NON-
98           LDH labels such as those used for SRV records), this function will
99           not fail but return $label as-is if conversion would fail.
100
101           This function takes the same optional parameters as "to_ascii",
102           with the same defaults.
103
104           If $label is already in ASCII, this function will never fail but
105           return $label as is as a last resort (i.e. pass-through).
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107           This function takes the following optional parameters (%param):
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109           AllowUnassigned
110           UseSTD3ASCIIRules
111               See "to_unicode" above. Please note that there is no need for
112               "TransitionalProcessing" for "to_unicode".
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114           This function does not handle strings that consist of multiple
115           labels (such as domain names). Use "domain_to_unicode" instead.
116
117       domain_to_ascii( $label, %param )
118           Converts all labels of the hostname $domain (with labels separated
119           by dots) to ASCII (using "to_ascii"). Will throw an exception on
120           invalid input.
121
122           This function takes the following optional parameters (%param):
123
124           AllowUnassigned
125           TransitionalProcessing
126               See "to_unicode" above.
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128           UseSTD3ASCIIRules
129               (boolean) If set to a true value, checks the label for
130               compliance with STD 3 (RFC 1123) syntax for host name parts.
131
132               The default is true (unlike "to_ascii").
133
134           This function will convert all dots to ASCII, i.e. to U+002E (full
135           stop). The following characters are recognized as dots: U+002E
136           (full stop), U+3002 (ideographic full stop), U+FF0E (fullwidth full
137           stop), U+FF61 (halfwidth ideographic full stop).
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139       domain_to_unicode( $domain, %param )
140           Converts all labels of the hostname $domain (with labels separated
141           by dots) to Unicode. Will throw an exception on invalid input.
142
143           This function takes the same optional parameters as
144           "domain_to_ascii", with the same defaults.
145
146           This function takes the following optional parameters (%param):
147
148           AllowUnassigned
149           UseSTD3ASCIIRules
150               See "domain_to_unicode" above. Please note that there is no
151               "TransitionalProcessing" for "domain_to_unicode".
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153           This function will preserve the original version of dots.  The
154           following characters are recognized as dots: U+002E (full stop),
155           U+3002 (ideographic full stop), U+FF0E (fullwidth full stop),
156           U+FF61 (halfwidth ideographic full stop).
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158       email_to_ascii( $email, %param )
159           Converts the domain part (right hand side, separated by an at sign)
160           of an RFC 2821/2822 email address to ASCII, using
161           "domain_to_ascii". May throw an exception on invalid input.
162
163           It takes the same parameters as "domain_to_ascii".
164
165           This function currently does not handle internationalization of the
166           local-part (left hand side). Future versions of this module might
167           implement an ASCII conversion for the local-part, should one be
168           standardized.
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170           This function will convert the at sign to ASCII, i.e. to U+0040
171           (commercial at), as well as label separators.  The following
172           characters are recognized as at signs: U+0040 (commercial at),
173           U+FE6B (small commercial at) and U+FF20 (fullwidth commercial at).
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175       email_to_unicode( $email, %param )
176           Converts the domain part (right hand side, separated by an at sign)
177           of an RFC 2821/2822 email address to Unicode, using
178           "domain_to_unicode". May throw an exception on invalid input.
179
180           It takes the same parameters as "domain_to_unicode".
181
182           This function currently does not handle internationalization of the
183           local-part (left hand side).  Future versions of this module might
184           implement a conversion from ASCII for the local-part, should one be
185           standardized.
186
187           This function will preserve the original version of at signs (and
188           label separators). The following characters are recognized as at
189           signs: U+0040 (commercial at), U+FE6B (small commercial at) and
190           U+FF20 (fullwidth commercial at).
191

AUTHOR

193       Claus Färber <CFAERBER@cpan.org>
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LICENSE

196       Copyright 2007-2014 Claus Färber.
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198       This library is free software; you can redistribute it and/or modify it
199       under the same terms as Perl itself.
200