Annotation of html5/spec/requirements-relating-to-bidirectional-algorithm-formatting-characters.html, revision 1.213
1.202 sruby 1: <!DOCTYPE html><html lang="en-US-x-Hixie"><meta charset="utf-8"><title>3.2.6 Requirements relating to bidirectional-algorithm formatting characters — HTML5</title><style type="text/css">
1.198 sruby 2:
3: .applies thead th > * { display: block; }
4: .applies thead code { display: block; }
5: .applies tbody th { white-space: nowrap; }
6: .applies td { text-align: center; }
7: .applies .yes { background: yellow; }
8:
9: .matrix, .matrix td { border: hidden; text-align: right; }
10: .matrix { margin-left: 2em; }
11:
12: .dice-example { border-collapse: collapse; border-style: hidden solid solid hidden; border-width: thin; margin-left: 3em; }
13: .dice-example caption { width: 30em; font-size: smaller; font-style: italic; padding: 0.75em 0; text-align: left; }
14: .dice-example td, .dice-example th { border: solid thin; width: 1.35em; height: 1.05em; text-align: center; padding: 0; }
15:
16: td.eg { border-width: thin; text-align: center; }
17:
18: #table-example-1 { border: solid thin; border-collapse: collapse; margin-left: 3em; }
19: #table-example-1 * { font-family: "Essays1743", serif; line-height: 1.01em; }
20: #table-example-1 caption { padding-bottom: 0.5em; }
21: #table-example-1 thead, #table-example-1 tbody { border: none; }
22: #table-example-1 th, #table-example-1 td { border: solid thin; }
23: #table-example-1 th { font-weight: normal; }
24: #table-example-1 td { border-style: none solid; vertical-align: top; }
25: #table-example-1 th { padding: 0.5em; vertical-align: middle; text-align: center; }
26: #table-example-1 tbody tr:first-child td { padding-top: 0.5em; }
27: #table-example-1 tbody tr:last-child td { padding-bottom: 1.5em; }
28: #table-example-1 tbody td:first-child { padding-left: 2.5em; padding-right: 0; width: 9em; }
29: #table-example-1 tbody td:first-child::after { content: leader(". "); }
30: #table-example-1 tbody td { padding-left: 2em; padding-right: 2em; }
31: #table-example-1 tbody td:first-child + td { width: 10em; }
32: #table-example-1 tbody td:first-child + td ~ td { width: 2.5em; }
33: #table-example-1 tbody td:first-child + td + td + td ~ td { width: 1.25em; }
34:
35: .apple-table-examples { border: none; border-collapse: separate; border-spacing: 1.5em 0em; width: 40em; margin-left: 3em; }
36: .apple-table-examples * { font-family: "Times", serif; }
37: .apple-table-examples td, .apple-table-examples th { border: none; white-space: nowrap; padding-top: 0; padding-bottom: 0; }
38: .apple-table-examples tbody th:first-child { border-left: none; width: 100%; }
39: .apple-table-examples thead th:first-child ~ th { font-size: smaller; font-weight: bolder; border-bottom: solid 2px; text-align: center; }
40: .apple-table-examples tbody th::after, .apple-table-examples tfoot th::after { content: leader(". ") }
41: .apple-table-examples tbody th, .apple-table-examples tfoot th { font: inherit; text-align: left; }
42: .apple-table-examples td { text-align: right; vertical-align: top; }
43: .apple-table-examples.e1 tbody tr:last-child td { border-bottom: solid 1px; }
44: .apple-table-examples.e1 tbody + tbody tr:last-child td { border-bottom: double 3px; }
45: .apple-table-examples.e2 th[scope=row] { padding-left: 1em; }
46: .apple-table-examples sup { line-height: 0; }
47:
48: .details-example img { vertical-align: top; }
49:
50: #base64-table {
51: white-space: nowrap;
52: font-size: 0.6em;
53: column-width: 6em;
54: column-count: 5;
55: column-gap: 1em;
56: -moz-column-width: 6em;
57: -moz-column-count: 5;
58: -moz-column-gap: 1em;
59: -webkit-column-width: 6em;
60: -webkit-column-count: 5;
61: -webkit-column-gap: 1em;
62: }
63: #base64-table thead { display: none; }
64: #base64-table * { border: none; }
65: #base64-table tbody td:first-child:after { content: ':'; }
66: #base64-table tbody td:last-child { text-align: right; }
67:
68: #named-character-references-table {
69: white-space: nowrap;
70: font-size: 0.6em;
71: column-width: 30em;
72: column-gap: 1em;
73: -moz-column-width: 30em;
74: -moz-column-gap: 1em;
75: -webkit-column-width: 30em;
76: -webkit-column-gap: 1em;
77: }
78: #named-character-references-table > table > tbody > tr > td:first-child + td,
79: #named-character-references-table > table > tbody > tr > td:last-child { text-align: center; }
80: #named-character-references-table > table > tbody > tr > td:last-child:hover > span { position: absolute; top: auto; left: auto; margin-left: 0.5em; line-height: 1.2; font-size: 5em; border: outset; padding: 0.25em 0.5em; background: white; width: 1.25em; height: auto; text-align: center; }
81: #named-character-references-table > table > tbody > tr#entity-CounterClockwiseContourIntegral > td:first-child { font-size: 0.5em; }
82:
83: .glyph.control { color: red; }
84:
85: @font-face {
86: font-family: 'Essays1743';
1.204 sruby 87: src: url('fonts/Essays1743.ttf');
1.198 sruby 88: }
89: @font-face {
90: font-family: 'Essays1743';
91: font-weight: bold;
1.204 sruby 92: src: url('fonts/Essays1743-Bold.ttf');
1.198 sruby 93: }
94: @font-face {
95: font-family: 'Essays1743';
96: font-style: italic;
1.204 sruby 97: src: url('fonts/Essays1743-Italic.ttf');
1.198 sruby 98: }
99: @font-face {
100: font-family: 'Essays1743';
101: font-style: italic;
102: font-weight: bold;
1.204 sruby 103: src: url('fonts/Essays1743-BoldItalic.ttf');
1.198 sruby 104: }
105:
1.202 sruby 106: </style><link href="data:text/css," id="complete" rel="stylesheet" title="Complete specification"><link href="data:text/css,.impl%20{%20display:%20none;%20}%0Ahtml%20{%20border:%20solid%20yellow;%20}%20.domintro:before%20{%20display:%20none;%20}" id="author" rel="alternate stylesheet" title="Author documentation only"><link href="data:text/css,.impl%20{%20background:%20%23FFEEEE;%20}%20.domintro:before%20{%20background:%20%23FFEEEE;%20}" id="highlight" rel="alternate stylesheet" title="Highlight implementation requirements"><style type="text/css">
1.1 mike 107: pre { margin-left: 2em; white-space: pre-wrap; }
108: h2 { margin: 3em 0 1em 0; }
109: h3 { margin: 2.5em 0 1em 0; }
110: h4 { margin: 2.5em 0 0.75em 0; }
111: h5, h6 { margin: 2.5em 0 1em; }
112: h1 + h2, h1 + h2 + h2 { margin: 0.75em 0 0.75em; }
113: h2 + h3, h3 + h4, h4 + h5, h5 + h6 { margin-top: 0.5em; }
114: p { margin: 1em 0; }
115: hr:not(.top) { display: block; background: none; border: none; padding: 0; margin: 2em 0; height: auto; }
116: dl, dd { margin-top: 0; margin-bottom: 0; }
117: dt { margin-top: 0.75em; margin-bottom: 0.25em; clear: left; }
118: dt + dt { margin-top: 0; }
119: dd dt { margin-top: 0.25em; margin-bottom: 0; }
120: dd p { margin-top: 0; }
121: dd dl + p { margin-top: 1em; }
122: dd table + p { margin-top: 1em; }
123: p + * > li, dd li { margin: 1em 0; }
124: dt, dfn { font-weight: bold; font-style: normal; }
125: i, em { font-style: italic; }
126: dt dfn { font-style: italic; }
127: pre, code { font-size: inherit; font-family: monospace; font-variant: normal; }
128: pre strong { color: black; font: inherit; font-weight: bold; background: yellow; }
129: pre em { font-weight: bolder; font-style: normal; }
130: @media screen { code { color: orangered; } code :link, code :visited { color: inherit; } }
131: var sub { vertical-align: bottom; font-size: smaller; position: relative; top: 0.1em; }
132: table { border-collapse: collapse; border-style: hidden hidden none hidden; }
133: table thead, table tbody { border-bottom: solid; }
134: table tbody th:first-child { border-left: solid; }
135: table tbody th { text-align: left; }
136: table td, table th { border-left: solid; border-right: solid; border-bottom: solid thin; vertical-align: top; padding: 0.2em; }
137: blockquote { margin: 0 0 0 2em; border: 0; padding: 0; font-style: italic; }
138:
139: .bad, .bad *:not(.XXX) { color: gray; border-color: gray; background: transparent; }
140: .matrix, .matrix td { border: none; text-align: right; }
141: .matrix { margin-left: 2em; }
142: .dice-example { border-collapse: collapse; border-style: hidden solid solid hidden; border-width: thin; margin-left: 3em; }
143: .dice-example caption { width: 30em; font-size: smaller; font-style: italic; padding: 0.75em 0; text-align: left; }
144: .dice-example td, .dice-example th { border: solid thin; width: 1.35em; height: 1.05em; text-align: center; padding: 0; }
145:
146: .toc dfn, h1 dfn, h2 dfn, h3 dfn, h4 dfn, h5 dfn, h6 dfn { font: inherit; }
147: img.extra, p.overview { float: right; }
148: pre.idl { border: solid thin; background: #EEEEEE; color: black; padding: 0.5em 1em; position: relative; }
149: pre.idl :link, pre.idl :visited { color: inherit; background: transparent; }
150: pre.idl::before { content: "IDL"; font: bold small sans-serif; padding: 0.5em; background: white; position: absolute; top: 0; margin: -1px 0 0 -4em; width: 1.5em; border: thin solid; border-radius: 0 0 0 0.5em }
151: pre.css { border: solid thin; background: #FFFFEE; color: black; padding: 0.5em 1em; }
152: pre.css:first-line { color: #AAAA50; }
153: dl.domintro { color: green; margin: 2em 0 2em 2em; padding: 0.5em 1em; border: none; background: #DDFFDD; }
154: hr + dl.domintro, div.impl + dl.domintro { margin-top: 2.5em; margin-bottom: 1.5em; }
155: dl.domintro dt, dl.domintro dt * { color: black; text-decoration: none; }
156: dl.domintro dd { margin: 0.5em 0 1em 2em; padding: 0; }
157: dl.domintro dd p { margin: 0.5em 0; }
158: dl.domintro:before { display: table; margin: -1em -0.5em -0.5em auto; width: auto; content: 'This box is non-normative. Implementation requirements are given below this box.'; color: black; font-style: italic; border: solid 2px; background: white; padding: 0 0.25em; }
159: dl.switch { padding-left: 2em; }
160: dl.switch > dt { text-indent: -1.5em; }
161: dl.switch > dt:before { content: '\21AA'; padding: 0 0.5em 0 0; display: inline-block; width: 1em; text-align: right; line-height: 0.5em; }
162: dl.triple { padding: 0 0 0 1em; }
163: dl.triple dt, dl.triple dd { margin: 0; display: inline }
164: dl.triple dt:after { content: ':'; }
165: dl.triple dd:after { content: '\A'; white-space: pre; }
166: .diff-old { text-decoration: line-through; color: silver; background: transparent; }
167: .diff-chg, .diff-new { text-decoration: underline; color: green; background: transparent; }
168: a .diff-new { border-bottom: 1px blue solid; }
169:
1.180 sruby 170: figure.diagrams { border: double black; background: white; padding: 1em; }
171: figure.diagrams img { display: block; margin: 1em auto; }
172:
1.1 mike 173: h2 { page-break-before: always; }
174: h1, h2, h3, h4, h5, h6 { page-break-after: avoid; }
175: h1 + h2, hr + h2.no-toc { page-break-before: auto; }
176:
177: p > span:not([title=""]):not([class="XXX"]):not([class="impl"]):not([class="note"]),
1.198 sruby 178: li > span:not([title=""]):not([class="XXX"]):not([class="impl"]):not([class="note"]) { border-bottom: solid #9999CC; }
1.1 mike 179:
180: div.head { margin: 0 0 1em; padding: 1em 0 0 0; }
181: div.head p { margin: 0; }
182: div.head h1 { margin: 0; }
183: div.head .logo { float: right; margin: 0 1em; }
184: div.head .logo img { border: none } /* remove border from top image */
185: div.head dl { margin: 1em 0; }
186: div.head p.copyright, div.head p.alt { font-size: x-small; font-style: oblique; margin: 0; }
187:
188: body > .toc > li { margin-top: 1em; margin-bottom: 1em; }
189: body > .toc.brief > li { margin-top: 0.35em; margin-bottom: 0.35em; }
190: body > .toc > li > * { margin-bottom: 0.5em; }
191: body > .toc > li > * > li > * { margin-bottom: 0.25em; }
192: .toc, .toc li { list-style: none; }
193:
194: .brief { margin-top: 1em; margin-bottom: 1em; line-height: 1.1; }
195: .brief li { margin: 0; padding: 0; }
196: .brief li p { margin: 0; padding: 0; }
197:
198: .category-list { margin-top: -0.75em; margin-bottom: 1em; line-height: 1.5; }
199: .category-list::before { content: '\21D2\A0'; font-size: 1.2em; font-weight: 900; }
200: .category-list li { display: inline; }
201: .category-list li:not(:last-child)::after { content: ', '; }
202: .category-list li > span, .category-list li > a { text-transform: lowercase; }
203: .category-list li * { text-transform: none; } /* don't affect <code> nested in <a> */
204:
205: .XXX { color: #E50000; background: white; border: solid red; padding: 0.5em; margin: 1em 0; }
206: .XXX > :first-child { margin-top: 0; }
207: p .XXX { line-height: 3em; }
208: .annotation { border: solid thin black; background: #0C479D; color: white; position: relative; margin: 8px 0 20px 0; }
209: .annotation:before { position: absolute; left: 0; top: 0; width: 100%; height: 100%; margin: 6px -6px -6px 6px; background: #333333; z-index: -1; content: ''; }
210: .annotation :link, .annotation :visited { color: inherit; }
211: .annotation :link:hover, .annotation :visited:hover { background: transparent; }
212: .annotation span { border: none ! important; }
213: .note { color: green; background: transparent; font-family: sans-serif; }
214: .warning { color: red; background: transparent; }
215: .note, .warning { font-weight: bolder; font-style: italic; }
216: .note em, .warning em, .note i, .warning i { font-style: normal; }
217: p.note, div.note { padding: 0.5em 2em; }
218: span.note { padding: 0 2em; }
219: .note p:first-child, .warning p:first-child { margin-top: 0; }
220: .note p:last-child, .warning p:last-child { margin-bottom: 0; }
221: .warning:before { font-style: normal; }
222: p.note:before { content: 'Note: '; }
223: p.warning:before { content: '\26A0 Warning! '; }
224:
225: .bookkeeping:before { display: block; content: 'Bookkeeping details'; font-weight: bolder; font-style: italic; }
226: .bookkeeping { font-size: 0.8em; margin: 2em 0; }
227: .bookkeeping p { margin: 0.5em 2em; display: list-item; list-style: square; }
228: .bookkeeping dt { margin: 0.5em 2em 0; }
229: .bookkeeping dd { margin: 0 3em 0.5em; }
230:
231: h4 { position: relative; z-index: 3; }
232: h4 + .element, h4 + div + .element { margin-top: -2.5em; padding-top: 2em; }
233: .element {
234: background: #EEEEFF;
235: color: black;
236: margin: 0 0 1em 0.15em;
237: padding: 0 1em 0.25em 0.75em;
238: border-left: solid #9999FF 0.25em;
239: position: relative;
240: z-index: 1;
241: }
242: .element:before {
243: position: absolute;
244: z-index: 2;
245: top: 0;
246: left: -1.15em;
247: height: 2em;
248: width: 0.9em;
249: background: #EEEEFF;
250: content: ' ';
251: border-style: none none solid solid;
252: border-color: #9999FF;
253: border-width: 0.25em;
254: }
255:
256: .example { display: block; color: #222222; background: #FCFCFC; border-left: double; margin-left: 2em; padding-left: 1em; }
257: td > .example:only-child { margin: 0 0 0 0.1em; }
258:
259: ul.domTree, ul.domTree ul { padding: 0 0 0 1em; margin: 0; }
260: ul.domTree li { padding: 0; margin: 0; list-style: none; position: relative; }
261: ul.domTree li li { list-style: none; }
262: ul.domTree li:first-child::before { position: absolute; top: 0; height: 0.6em; left: -0.75em; width: 0.5em; border-style: none none solid solid; content: ''; border-width: 0.1em; }
263: ul.domTree li:not(:last-child)::after { position: absolute; top: 0; bottom: -0.6em; left: -0.75em; width: 0.5em; border-style: none none solid solid; content: ''; border-width: 0.1em; }
264: ul.domTree span { font-style: italic; font-family: serif; }
265: ul.domTree .t1 code { color: purple; font-weight: bold; }
266: ul.domTree .t2 { font-style: normal; font-family: monospace; }
267: ul.domTree .t2 .name { color: black; font-weight: bold; }
268: ul.domTree .t2 .value { color: blue; font-weight: normal; }
269: ul.domTree .t3 code, .domTree .t4 code, .domTree .t5 code { color: gray; }
270: ul.domTree .t7 code, .domTree .t8 code { color: green; }
271: ul.domTree .t10 code { color: teal; }
272:
273: body.dfnEnabled dfn { cursor: pointer; }
274: .dfnPanel {
275: display: inline;
276: position: absolute;
277: z-index: 10;
278: height: auto;
279: width: auto;
280: padding: 0.5em 0.75em;
281: font: small sans-serif, Droid Sans Fallback;
282: background: #DDDDDD;
283: color: black;
284: border: outset 0.2em;
285: }
286: .dfnPanel * { margin: 0; padding: 0; font: inherit; text-indent: 0; }
287: .dfnPanel :link, .dfnPanel :visited { color: black; }
288: .dfnPanel p { font-weight: bolder; }
289: .dfnPanel * + p { margin-top: 0.25em; }
290: .dfnPanel li { list-style-position: inside; }
291:
292: #configUI { position: absolute; z-index: 20; top: 10em; right: 1em; width: 11em; font-size: small; }
293: #configUI p { margin: 0.5em 0; padding: 0.3em; background: #EEEEEE; color: black; border: inset thin; }
294: #configUI p label { display: block; }
295: #configUI #updateUI, #configUI .loginUI { text-align: center; }
296: #configUI input[type=button] { display: block; margin: auto; }
297:
298: fieldset { margin: 1em; padding: 0.5em 1em; }
299: fieldset > legend + * { margin-top: 0; }
300: fieldset > :last-child { margin-bottom: 0; }
301: fieldset p { margin: 0.5em 0; }
302:
1.205 sruby 303: </style><link href="http://www.w3.org/StyleSheets/TR/W3C-ED" rel="stylesheet" type="text/css"><script>
1.1 mike 304: function getCookie(name) {
305: var params = location.search.substr(1).split("&");
306: for (var index = 0; index < params.length; index++) {
307: if (params[index] == name)
308: return "1";
309: var data = params[index].split("=");
310: if (data[0] == name)
311: return unescape(data[1]);
312: }
313: var cookies = document.cookie.split("; ");
314: for (var index = 0; index < cookies.length; index++) {
315: var data = cookies[index].split("=");
316: if (data[0] == name)
317: return unescape(data[1]);
318: }
319: return null;
320: }
1.202 sruby 321: </script><link href="content-models.html" rel="prev" title="3.2.5 Content models">
322: <link href="index.html#contents" rel="contents" title="Table of contents">
323: <link href="wai-aria.html" rel="next" title="3.2.7 WAI-ARIA">
324: <body class="split chapter" onload="fixBrokenLink();"><div class="head" id="head">
1.1 mike 325: <p><a href="http://www.w3.org/"><img alt="W3C" height="48" src="http://www.w3.org/Icons/w3c_home" width="72"></a></p>
326:
327: <h1>HTML5</h1>
1.195 sruby 328: <h2 class="no-num no-toc" id="a-vocabulary-and-associated-apis-for-html-and-xhtml">A vocabulary and associated APIs for HTML and XHTML</h2>
1.213 ! sruby 329: <h2 class="no-num no-toc" id="editor's-draft-date-1-january-1970">Editor's Draft 21 November 2012</h2>
1.85 mike 330: </div>
1.198 sruby 331:
332:
1.202 sruby 333: <nav class="prev_next">
334: <a href="content-models.html">← 3.2.5 Content models</a> –
335: <a href="index.html#contents">Table of contents</a> –
336: <a href="wai-aria.html">3.2.7 WAI-ARIA →</a>
337: </nav>
1.1 mike 338:
339: <h4 id="requirements-relating-to-bidirectional-algorithm-formatting-characters"><span class="secno">3.2.6 </span>Requirements relating to bidirectional-algorithm formatting
1.85 mike 340: characters</h4>
341:
342: <p><a href="content-models.html#text-content">Text content</a> in <a href="infrastructure.html#html-elements">HTML elements</a> with
1.159 sruby 343: child <code><a href="infrastructure.html#text-0">Text</a></code> nodes, and text in attributes of <a href="infrastructure.html#html-elements">HTML
1.46 mike 344: elements</a> that allow free-form text, may contain characters in
345: the range U+202A to U+202E (the bidirectional-algorithm formatting
346: characters). However, the use of these characters is restricted so
347: that any embedding or overrides generated by these characters do not
348: start and end with different parent elements, and so that all such
349: embeddings and overrides are explicitly terminated by a U+202C POP
350: DIRECTIONAL FORMATTING character. This helps reduce incidences of
351: text being reused in a manner that has unforeseen effects on the
1.203 sruby 352: bidirectional algorithm. <a href="references.html#refsBIDI">[BIDI]</a></p>
1.85 mike 353:
354: <p>The aforementioned restrictions are defined by specifying that
1.1 mike 355: certain parts of documents form <a href="#bidirectional-algorithm-formatting-character-ranges">bidirectional-algorithm
356: formatting character ranges</a>, and then imposing a requirement
1.85 mike 357: on such ranges.</p>
358:
359: <p>The strings resulting from applying the following algorithm to an
1.1 mike 360: <a href="infrastructure.html#html-elements" title="HTML elements">HTML element</a> <var title="">element</var> are <a href="#bidirectional-algorithm-formatting-character-ranges">bidirectional-algorithm formatting
1.85 mike 361: character ranges</a>:</p>
362:
1.202 sruby 363: <ol><li><p>Let <var title="">output</var> be an empty list of strings.</li>
1.1 mike 364:
1.202 sruby 365: <li><p>Let <var title="">string</var> be an empty string.</li>
1.1 mike 366:
1.202 sruby 367: <li><p>Let <var title="">node</var> be the first child node of <var title="">element</var>, if any, or null otherwise.</li>
1.1 mike 368:
1.159 sruby 369: <!-- while node != null do -->
1.1 mike 370: <li><p><i>Loop</i>: If <var title="">node</var> is null, jump to
1.202 sruby 371: the step labeled <i>end</i>.</li>
1.1 mike 372:
373: <li>
374:
375: <p>Process <var title="">node</var> according to the first
376: matching step from the following list:</p>
377:
1.159 sruby 378: <dl class="switch"><dt>If <var title="">node</var> is a <code><a href="infrastructure.html#text-0">Text</a></code> node</dt>
1.1 mike 379:
1.202 sruby 380: <dd><p>Append the text data of <var title="">node</var> to <var title="">string</var>.</dd>
1.1 mike 381:
382:
383: <dt>If <var title="">node</var> is a <code><a href="the-br-element.html#the-br-element">br</a></code> element</dt>
1.159 sruby 384: <dt>If <var title="">node</var> is an <a href="infrastructure.html#html-elements" title="HTML elements">HTML element</a> that is <a href="content-models.html#flow-content-1">flow content</a> but that is not also <a href="content-models.html#phrasing-content-1">phrasing content</a></dt>
1.1 mike 385:
386: <dd><p>If <var title="">string</var> is not the empty string,
387: push <var title="">string</var> onto <var title="">output</var>,
1.202 sruby 388: and let <var title="">string</var> be empty string.</dd>
1.1 mike 389:
390:
391: <dt>Otherwise</dt>
392:
393: <dd>Do nothing.</dd>
394:
395: </dl></li>
396:
397: <li><p>Let <var title="">node</var> be <var title="">node</var>'s
1.202 sruby 398: next sibling, if any, or null otherwise.</li>
1.1 mike 399:
1.202 sruby 400: <li><p>Jump to the step labeled <i>loop</i>.</li>
1.159 sruby 401: <!-- end while -->
1.1 mike 402:
403: <li><p><i>End</i>: If <var title="">string</var> is not the empty
1.202 sruby 404: string, push <var title="">string</var> onto <var title="">output</var>.</li>
1.1 mike 405:
406: <li><p>Return <var title="">output</var> as the
407: <a href="#bidirectional-algorithm-formatting-character-ranges">bidirectional-algorithm formatting character
1.202 sruby 408: ranges</a>.</li>
1.1 mike 409:
410: </ol><p>The value of a namespace-less attribute of an <a href="infrastructure.html#html-elements" title="HTML
411: elements">HTML element</a> is a <a href="#bidirectional-algorithm-formatting-character-ranges" title="bidirectional-algorithm formatting character
412: ranges">bidirectional-algorithm formatting character
1.85 mike 413: range</a>.</p>
414:
1.159 sruby 415: <!--(this is unnecessarily pedantic)
416: <p>The text data of a comment node is a <span
417: title="bidirectional-algorithm formatting character
418: ranges">bidirectional-algorithm formatting character
419: range</span>.</p>
420: -->
1.85 mike 421:
422: <p>Any strings that, as described above, are
1.1 mike 423: <dfn id="bidirectional-algorithm-formatting-character-ranges">bidirectional-algorithm formatting character ranges</dfn> must
424: match the <code title="">string</code> production in the following
1.203 sruby 425: ABNF, the character set for which is Unicode. <a href="references.html#refsABNF">[ABNF]</a></p>
1.85 mike 426:
427: <pre>string = *( plaintext ( embedding / override ) ) plaintext
1.1 mike 428: embedding = ( lre / rle ) string pdf
429: override = ( lro / rlo ) string pdf
430: lre = %x202A ; U+202A LEFT-TO-RIGHT EMBEDDING
431: rle = %x202B ; U+202B RIGHT-TO-LEFT EMBEDDING
432: lro = %x202D ; U+202D LEFT-TO-RIGHT OVERRIDE
433: rlo = %x202E ; U+202E RIGHT-TO-LEFT OVERRIDE
434: pdf = %x202C ; U+202C POP DIRECTIONAL FORMATTING
435: plaintext = *( %x0000-2029 / %x202F-10FFFF )
1.85 mike 436: ; any string with no bidirectional-algorithm formatting characters</pre>
437:
438: <p class="note">Authors are encouraged to use the <code title="attr-dir"><a href="global-attributes.html#the-dir-attribute">dir</a></code> attribute, the <code><a href="the-bdo-element.html#the-bdo-element">bdo</a></code> element,
1.1 mike 439: and the <code><a href="the-bdi-element.html#the-bdi-element">bdi</a></code> element, rather than maintaining the
440: bidirectional-algorithm formatting characters manually. The
441: bidirectional-algorithm formatting characters interact poorly with
1.85 mike 442: CSS.</p>
443:
444:
445:
1.202 sruby 446:
Webmaster
![[BACK]](/https/dev.w3.org/cvsweb/icons/back.gif){kind=icon}
Return to requirements-relating-to-bidirectional-algorithm-formatting-characters.html CVS log ![[TXT]](/https/dev.w3.org/cvsweb/icons/text.gif){kind=icon}
![[DIR]](/https/dev.w3.org/cvsweb/icons/dir.gif){kind=icon}
Up to [Public] / html5 / spec