1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
|
---
title: Espaços de nomes
slug: Archive/Mozilla/XUL/Namespaces
tags:
- Extensões
- Extras
translation_of: Archive/Mozilla/XUL/Namespaces
---
<p> </p>
<p>Em adição a este documento, consulte <em><a href="/pt-PT/docs/Web/SVG/Namespaces_Crash_Course" title="en/SVG/Namespaces_Crash_Course">Namespaces Crash Course</a></em>.</p>
<p><strong>Espaços de nomes XML </strong>fornecem uma maneira para distinguir nomes duplicados de elementos e atributos. Os nomes de elementos e atributos duplicados podem ocorrer quando um documento XML contém elementos e atributos de dois ou mais esquemas XML diferentes (ou DTDs). para citar <a class="external" href="https://pt.wikipedia.org/wiki/Espa%C3%A7o_de_nomes">Wikipédia</a>: "Em geral, um espaço de nome é um recipiente abstrato que fornece contexto para os itens... este contém e permite a desambiguação de itens com o mesmo nome."</p>
<p>If you are familiar with C++ namespaces, Java packages, perl packages, or Python module importing, you are already familiar with the namespace concept.</p>
<p>An XML namespace is identified by an unique name (called a URI, not a URL, even though it can look like a URL). An URI is any string, although most people choose a URL-based URI because URLs are an easy way to <em>hope</em> for uniqueness. Although there's nothing preventing someone else from using the namespace <code>http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul</code>, it's fairly unlikely anyone would choose that accidentally. Even if they did accidentally choose it, they may not define the same elements as XUL anyway (e.g., <code><textbox/></code>) in their schema/DTD.</p>
<p>Any element type or attribute name in an XML namespace can be uniquely identified by its XML namespace and its "local name". Together, these two items define a <em>qualified name</em>, or <a class="external" href="http://www.w3.org/TR/REC-xml-names/#dt-qualname">QName</a>.</p>
<p>For example, <code><xul:textbox/></code> uses a namespace named "xul" and a local name "textbox". This distinguishes it from, for example, <code><foobar:textbox/></code> which might occur in the same document. The <strong>xul</strong> and <strong>foobar</strong> namespaces must be defined at the top of the XML document in which they are used, like so:</p>
<pre> <foobar:some-element
xmlns:xul="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
xmlns:foobar="the-foobar-namespace">
<xul:textbox id="foo" value="bar"/>
<foobar:textbox favorite-food="pancakes"/>
</foobar:some-element>
</pre>
<p>Notice I've mixed two <code><textboxes/></code> in the same document. The only way to distinguish that they have different meanings is with namespaces.</p>
<p>There's only one other thing to know: "default namespace". Every XML element has a "default namespace", and this is used with XUL elements all the time. In XUL documents, you'll usually see this:</p>
<pre> <window
id="foo"
xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
...
...
</window>
</pre>
<p>and in XHTML documents, you'll see this:</p>
<pre> <html xmlns="http://www.w3.org/1999/xhtml">
...
...
</html>
</pre>
<p>There is a very subtle difference here than before. Before I wrote <code>xmlns<strong>:xul</strong>="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"</code> but here the <strong>:xul</strong> piece is omitted. This signifies to the XML parser that <code>http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul</code> is the <strong>default namespace</strong> for the element and its descendant elements (unless further overridden by a default namespace on a descendant element), and that any element without a namespace (i.e., no prefix and colon) belongs to the default namespace. That's why we can write the shorthand <code><textbox/></code> instead of <code><xul:textbox/></code> in XUL (although the latter is just as correct when not using <code>http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul</code> as the default namespace) -- the XUL namespace is defined as the default on the topmost element. In other words, a default namespace permits a kind of short-hand to be used for all descendants of an element.</p>
<p>Here's a question: what namespace contains the element <code>foo</code> in the XML document below?</p>
<pre> <foo/>
</pre>
<p>The answer is that it's in <strong>no</strong> namespace, or alternately, it's in the namespace denoted by the empty string:</p>
<pre> <foo xmlns=""/>
</pre>
<p>This second example is semantically equivalent to the first.</p>
<p>Now, a second question: what namespaces are the <code>bar</code>, <code>baz</code>, and <code>quux</code> attributes in?</p>
<pre> <foo bar="value">
<element xmlns="namespace!" baz="value">
<element quux="value"/>
</element>
</foo>
</pre>
<p><code>bar</code> is obviously not in a namespace. What about <code>baz</code> and <code>quux</code>? The answer is that they aren't in a namespace either. In fact no unprefixed attribute is ever in a namespace, primarily because XML originally didn't have namespaces, and all XML from that time had to stay in no namespace. This is a source of perennial confusion for XML namespaces.</p>
<div id="SL_balloon_obj" style="display: block;">
<div class="SL_ImTranslatorLogo" id="SL_button" style="background: rgba(0, 0, 0, 0) repeat scroll 0% 0%; opacity: 0; display: block; left: -8px; top: -25px; transition: visibility 2s ease 0s, opacity 2s linear 0s;"> </div>
<div id="SL_shadow_translation_result2" style="display: none;"> </div>
<div id="SL_shadow_translator" style="display: none;">
<div id="SL_planshet">
<div id="SL_arrow_up" style="background: rgba(0, 0, 0, 0) repeat scroll 0% 0%;"> </div>
<div id="SL_Bproviders">
<div class="SL_BL_LABLE_ON" id="SL_P0" title="Google">G</div>
<div class="SL_BL_LABLE_ON" id="SL_P1" title="Microsoft">M</div>
<div class="SL_BL_LABLE_ON" id="SL_P2" title="Translator">T</div>
</div>
<div id="SL_alert_bbl" style="display: none;">
<div id="SLHKclose" style="background: rgba(0, 0, 0, 0) repeat scroll 0% 0%;"> </div>
<div id="SL_alert_cont"> </div>
</div>
<div id="SL_TB">
<table id="SL_tables">
<tbody><tr>
<td class="SL_td"><input></td>
<td class="SL_td"><select><option value="auto">Detectar idioma</option><option value="af">Africâner</option><option value="sq">Albanês</option><option value="de">Alemão</option><option value="ar">Arabe</option><option value="hy">Armênio</option><option value="az">Azerbaijano</option><option value="eu">Basco</option><option value="bn">Bengali</option><option value="be">Bielo-russo</option><option value="my">Birmanês</option><option value="bs">Bósnio</option><option value="bg">Búlgaro</option><option value="ca">Catalão</option><option value="kk">Cazaque</option><option value="ceb">Cebuano</option><option value="ny">Chichewa</option><option value="zh-CN">Chinês (Simp)</option><option value="zh-TW">Chinês (Trad)</option><option value="si">Cingalês</option><option value="ko">Coreano</option><option value="ht">Crioulo haitiano</option><option value="hr">Croata</option><option value="da">Dinamarquês</option><option value="sk">Eslovaco</option><option value="sl">Esloveno</option><option value="es">Espanhol</option><option value="eo">Esperanto</option><option value="et">Estoniano</option><option value="fi">Finlandês</option><option value="fr">Francês</option><option value="gl">Galego</option><option value="cy">Galês</option><option value="ka">Georgiano</option><option value="el">Grego</option><option value="gu">Gujarati</option><option value="ha">Hauça</option><option value="iw">Hebraico</option><option value="hi">Hindi</option><option value="hmn">Hmong</option><option value="nl">Holandês</option><option value="hu">Húngaro</option><option value="ig">Igbo</option><option value="id">Indonésio</option><option value="en">Inglês</option><option value="yo">Ioruba</option><option value="ga">Irlandês</option><option value="is">Islandês</option><option value="it">Italiano</option><option value="ja">Japonês</option><option value="jw">Javanês</option><option value="kn">Kannada</option><option value="km">Khmer</option><option value="lo">Laosiano</option><option value="la">Latim</option><option value="lv">Letão</option><option value="lt">Lituano</option><option value="mk">Macedônico</option><option value="ml">Malaiala</option><option value="ms">Malaio</option><option value="mg">Malgaxe</option><option value="mt">Maltês</option><option value="mi">Maori</option><option value="mr">Marathi</option><option value="mn">Mongol</option><option value="ne">Nepalês</option><option value="no">Norueguês</option><option value="fa">Persa</option><option value="pl">Polonês</option><option value="pt">Português</option><option value="pa">Punjabi</option><option value="ro">Romeno</option><option value="ru">Russo</option><option value="sr">Sérvio</option><option value="st">Sesotho</option><option value="so">Somália</option><option value="sw">Suaíli</option><option value="su">Sudanês</option><option value="sv">Sueco</option><option value="tg">Tadjique</option><option value="tl">Tagalo</option><option value="th">Tailandês</option><option value="ta">Tâmil</option><option value="cs">Tcheco</option><option value="te">Telugo</option><option value="tr">Turco</option><option value="uk">Ucraniano</option><option value="ur">Urdu</option><option value="uz">Uzbeque</option><option value="vi">Vietnamita</option><option value="yi">Yiddish</option><option value="zu">Zulu</option></select></td>
<td class="SL_td">
<div id="SL_switch_b" style="background: rgba(0, 0, 0, 0) repeat scroll 0% 0%;" title="Alternar Idiomas"> </div>
</td>
<td class="SL_td"><select><option value="af">Africâner</option><option value="sq">Albanês</option><option value="de">Alemão</option><option value="ar">Arabe</option><option value="hy">Armênio</option><option value="az">Azerbaijano</option><option value="eu">Basco</option><option value="bn">Bengali</option><option value="be">Bielo-russo</option><option value="my">Birmanês</option><option value="bs">Bósnio</option><option value="bg">Búlgaro</option><option value="ca">Catalão</option><option value="kk">Cazaque</option><option value="ceb">Cebuano</option><option value="ny">Chichewa</option><option value="zh-CN">Chinês (Simp)</option><option value="zh-TW">Chinês (Trad)</option><option value="si">Cingalês</option><option value="ko">Coreano</option><option value="ht">Crioulo haitiano</option><option value="hr">Croata</option><option value="da">Dinamarquês</option><option value="sk">Eslovaco</option><option value="sl">Esloveno</option><option value="es">Espanhol</option><option value="eo">Esperanto</option><option value="et">Estoniano</option><option value="fi">Finlandês</option><option value="fr">Francês</option><option value="gl">Galego</option><option value="cy">Galês</option><option value="ka">Georgiano</option><option value="el">Grego</option><option value="gu">Gujarati</option><option value="ha">Hauça</option><option value="iw">Hebraico</option><option value="hi">Hindi</option><option value="hmn">Hmong</option><option value="nl">Holandês</option><option value="hu">Húngaro</option><option value="ig">Igbo</option><option value="id">Indonésio</option><option selected value="en">Inglês</option><option value="yo">Ioruba</option><option value="ga">Irlandês</option><option value="is">Islandês</option><option value="it">Italiano</option><option value="ja">Japonês</option><option value="jw">Javanês</option><option value="kn">Kannada</option><option value="km">Khmer</option><option value="lo">Laosiano</option><option value="la">Latim</option><option value="lv">Letão</option><option value="lt">Lituano</option><option value="mk">Macedônico</option><option value="ml">Malaiala</option><option value="ms">Malaio</option><option value="mg">Malgaxe</option><option value="mt">Maltês</option><option value="mi">Maori</option><option value="mr">Marathi</option><option value="mn">Mongol</option><option value="ne">Nepalês</option><option value="no">Norueguês</option><option value="fa">Persa</option><option value="pl">Polonês</option><option value="pt">Português</option><option value="pa">Punjabi</option><option value="ro">Romeno</option><option value="ru">Russo</option><option value="sr">Sérvio</option><option value="st">Sesotho</option><option value="so">Somália</option><option value="sw">Suaíli</option><option value="su">Sudanês</option><option value="sv">Sueco</option><option value="tg">Tadjique</option><option value="tl">Tagalo</option><option value="th">Tailandês</option><option value="ta">Tâmil</option><option value="cs">Tcheco</option><option value="te">Telugo</option><option value="tr">Turco</option><option value="uk">Ucraniano</option><option value="ur">Urdu</option><option value="uz">Uzbeque</option><option value="vi">Vietnamita</option><option value="yi">Yiddish</option><option value="zu">Zulu</option></select></td>
<td class="SL_td">
<div id="SL_TTS_voice" style="background: rgba(0, 0, 0, 0) repeat scroll 0% 0%;" title="Ouça"> </div>
</td>
<td class="SL_td">
<div class="SL_copy" id="SL_copy" style="background: rgba(0, 0, 0, 0) repeat scroll 0% 0%;" title="Copiar"> </div>
</td>
<td class="SL_td">
<div id="SL_bbl_font_patch"> </div>
<div class="SL_bbl_font" id="SL_bbl_font" style="background: rgba(0, 0, 0, 0) repeat scroll 0% 0%;" title="Tamanho da fonte"> </div>
</td>
<td class="SL_td">
<div id="SL_bbl_help" style="background: rgba(0, 0, 0, 0) repeat scroll 0% 0%;" title="Ajuda"> </div>
</td>
<td class="SL_td">
<div class="SL_pin_off" id="SL_pin" style="background: rgba(0, 0, 0, 0) repeat scroll 0% 0%;" title="Fixar a janela de pop-up"> </div>
</td>
</tr>
</tbody></table>
</div>
</div>
<div id="SL_shadow_translation_result" style=""> </div>
<div class="SL_loading" id="SL_loading" style="background: rgba(0, 0, 0, 0) repeat scroll 0% 0%;"> </div>
<div id="SL_player2"> </div>
<div id="SL_alert100">A função de fala é limitada a 200 caracteres</div>
<div id="SL_Balloon_options" style="background: rgb(255, 255, 255) repeat scroll 0% 0%;">
<div id="SL_arrow_down" style="background: rgba(0, 0, 0, 0) repeat scroll 0% 0%;"> </div>
<table id="SL_tbl_opt" style="width: 100%;">
<tbody><tr>
<td><input></td>
<td>
<div id="SL_BBL_IMG" style="background: rgba(0, 0, 0, 0) repeat scroll 0% 0%;" title="Mostrar o botão do ImTranslator 3 segundos"> </div>
</td>
<td><a class="SL_options" title="Mostrar opções">Opções</a> : <a class="SL_options" title="Histórico de tradução">Histórico</a> : <a class="SL_options" title="Comentários">Comentários</a> : <a class="SL_options" href="https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=GD9D8CPW8HFA2" title="Faça sua contribuição">Donate</a></td>
<td><span id="SL_Balloon_Close" title="Encerrar">Encerrar</span></td>
</tr>
</tbody></table>
</div>
</div>
</div>
|
