Annotation of html5/spec-author-view/scripting-1.html, revision 1.9
1.9 ! mike 1: <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN">
! 2: <!DOCTYPE html>
! 3: <!-- when publishing, change bits marked ZZZ --><html lang="en-US-x-Hixie" class="split chapter"><head><title>4.3 Scripting — HTML5 (Author Edition)</title><script src="link-fixup.js"></script><link href="whatwg.css" rel="stylesheet"><style type="text/css">
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! 17: dd p { margin-top: 0; }
! 18: dd dl + p { margin-top: 1em; }
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! 24: pre strong { color: black; font: inherit; font-weight: bold; background: yellow; }
! 25: pre em { font-weight: bolder; font-style: normal; }
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! 27: var sub { vertical-align: bottom; font-size: smaller; position: relative; top: 0.1em; }
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! 33: blockquote { margin: 0 0 0 2em; border: 0; padding: 0; font-style: italic; }
! 34:
! 35: .bad, .bad *:not(.XXX) { color: gray; border-color: gray; background: transparent; }
! 36: .matrix, .matrix td { border: none; text-align: right; }
! 37: .matrix { margin-left: 2em; }
! 38: .dice-example { border-collapse: collapse; border-style: hidden solid solid hidden; border-width: thin; margin-left: 3em; }
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! 41:
! 42: .toc dfn, h1 dfn, h2 dfn, h3 dfn, h4 dfn, h5 dfn, h6 dfn { font: inherit; }
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! 47: pre.css:first-line { color: #AAAA50; }
! 48: dl.domintro { color: green; margin: 2em 0 2em 2em; padding: 0.5em 1em; border: none; background: #EEFFEE; }
! 49: hr + dl.domintro, div.impl + dl.domintro { margin-top: 2.5em; margin-bottom: 1.5em; }
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! 53: dl.switch { padding-left: 2em; }
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! 60: .diff-old { text-decoration: line-through; color: silver; background: transparent; }
! 61: .diff-chg, .diff-new { text-decoration: underline; color: green; background: transparent; }
! 62: a .diff-new { border-bottom: 1px blue solid; }
! 63:
! 64: h2 { page-break-before: always; }
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! 67:
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! 69:
! 70: div.head { margin: 0 0 1em; padding: 1em 0 0 0; }
! 71: div.head p { margin: 0; }
! 72: div.head h1 { margin: 0; }
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! 74: div.head .logo img { border: none } /* remove border from top image */
! 75: div.head dl { margin: 1em 0; }
! 76: div.head p.copyright, div.head p.alt { font-size: x-small; font-style: oblique; margin: 0; }
! 77:
! 78: body > .toc > li { margin-top: 1em; margin-bottom: 1em; }
! 79: body > .toc.brief > li { margin-top: 0.35em; margin-bottom: 0.35em; }
! 80: body > .toc > li > * { margin-bottom: 0.5em; }
! 81: body > .toc > li > * > li > * { margin-bottom: 0.25em; }
! 82: .toc, .toc li { list-style: none; }
! 83:
! 84: .brief { margin-top: 1em; margin-bottom: 1em; line-height: 1.1; }
! 85: .brief li { margin: 0; padding: 0; }
! 86: .brief li p { margin: 0; padding: 0; }
! 87:
! 88: .category-list { margin-top: -0.75em; margin-bottom: 1em; line-height: 1.5; }
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! 90: .category-list li { display: inline; }
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! 92: .category-list li > span, .category-list li > a { text-transform: lowercase; }
! 93: .category-list li * { text-transform: none; } /* don't affect <code> nested in <a> */
! 94:
! 95: .XXX { color: #E50000; background: white; border: solid red; padding: 0.5em; margin: 1em 0; }
! 96: .XXX > :first-child { margin-top: 0; }
! 97: p .XXX { line-height: 3em; }
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! 100: .annotation :link, .annotation :visited { color: inherit; }
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! 102: .annotation span { border: none ! important; }
! 103: .note { color: green; background: transparent; font-family: sans-serif; }
! 104: .warning { color: red; background: transparent; }
! 105: .note, .warning { font-weight: bolder; font-style: italic; }
! 106: p.note, div.note { padding: 0.5em 2em; }
! 107: span.note { padding: 0 2em; }
! 108: .note p:first-child, .warning p:first-child { margin-top: 0; }
! 109: .note p:last-child, .warning p:last-child { margin-bottom: 0; }
! 110: .warning:before { font-style: normal; }
! 111: p.note:before { content: 'Note: '; }
! 112: p.warning:before { content: '\26A0 Warning! '; }
! 113:
! 114: .bookkeeping:before { display: block; content: 'Bookkeeping details'; font-weight: bolder; font-style: italic; }
! 115: .bookkeeping { font-size: 0.8em; margin: 2em 0; }
! 116: .bookkeeping p { margin: 0.5em 2em; display: list-item; list-style: square; }
! 117:
! 118: h4 { position: relative; z-index: 3; }
! 119: h4 + .element, h4 + div + .element { margin-top: -2.5em; padding-top: 2em; }
! 120: .element {
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! 123: margin: 0 0 1em 0.15em;
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! 126: position: relative;
! 127: z-index: 1;
! 128: }
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! 136: background: #EEEEFF;
! 137: content: ' ';
! 138: border-style: none none solid solid;
! 139: border-color: #9999FF;
! 140: border-width: 0.25em;
! 141: }
! 142:
! 143: .example { display: block; color: #222222; background: #FCFCFC; border-left: double; margin-left: 2em; padding-left: 1em; }
! 144: td > .example:only-child { margin: 0 0 0 0.1em; }
! 145:
! 146: .tall-and-narrow {
! 147: font-size: 0.6em;
! 148: column-width: 25em;
! 149: column-gap: 1em;
! 150: -moz-column-width: 25em;
! 151: -moz-column-gap: 1em;
! 152: -webkit-column-width: 25em;
! 153: -webkit-column-gap: 1em;
! 154: }
! 155:
! 156: ul.domTree, ul.domTree ul { padding: 0 0 0 1em; margin: 0; }
! 157: ul.domTree li { padding: 0; margin: 0; list-style: none; position: relative; }
! 158: ul.domTree li li { list-style: none; }
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! 160: 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; }
! 161: ul.domTree span { font-style: italic; font-family: serif; }
! 162: ul.domTree .t1 code { color: purple; font-weight: bold; }
! 163: ul.domTree .t2 { font-style: normal; font-family: monospace; }
! 164: ul.domTree .t2 .name { color: black; font-weight: bold; }
! 165: ul.domTree .t2 .value { color: blue; font-weight: normal; }
! 166: ul.domTree .t3 code, .domTree .t4 code, .domTree .t5 code { color: gray; }
! 167: ul.domTree .t7 code, .domTree .t8 code { color: green; }
! 168: ul.domTree .t10 code { color: teal; }
! 169:
! 170: #configUI { position: absolute; z-index: 20; top: 10em; right: 1em; width: 11em; font-size: small; }
! 171: #configUI p { margin: 0.5em 0; padding: 0.3em; background: #EEEEEE; color: black; border: inset thin; }
! 172: #configUI p label { display: block; }
! 173: #configUI #updateUI, #configUI .loginUI { text-align: center; }
! 174: #configUI input[type=button] { display: block; margin: auto; }
! 175: </style><style type="text/css">
! 176:
! 177: .applies thead th > * { display: block; }
! 178: .applies thead code { display: block; }
! 179: .applies tbody th { whitespace: nowrap; }
! 180: .applies td { text-align: center; }
! 181: .applies .yes { background: yellow; }
! 182:
! 183: .matrix, .matrix td { border: none; text-align: right; }
! 184: .matrix { margin-left: 2em; }
! 185:
! 186: .dice-example { border-collapse: collapse; border-style: hidden solid solid hidden; border-width: thin; margin-left: 3em; }
! 187: .dice-example caption { width: 30em; font-size: smaller; font-style: italic; padding: 0.75em 0; text-align: left; }
! 188: .dice-example td, .dice-example th { border: solid thin; width: 1.35em; height: 1.05em; text-align: center; padding: 0; }
! 189:
! 190: #table-example-1 { border: solid thin; border-collapse: collapse; margin-left: 3em; }
! 191: #table-example-1 * { font-family: "Essays1743", serif; line-height: 1.01em; }
! 192: #table-example-1 caption { padding-bottom: 0.5em; }
! 193: #table-example-1 thead, #table-example-1 tbody { border: none; }
! 194: #table-example-1 th, #table-example-1 td { border: solid thin; }
! 195: #table-example-1 th { font-weight: normal; }
! 196: #table-example-1 td { border-style: none solid; vertical-align: top; }
! 197: #table-example-1 th { padding: 0.5em; vertical-align: middle; text-align: center; }
! 198: #table-example-1 tbody tr:first-child td { padding-top: 0.5em; }
! 199: #table-example-1 tbody tr:last-child td { padding-bottom: 1.5em; }
! 200: #table-example-1 tbody td:first-child { padding-left: 2.5em; padding-right: 0; width: 9em; }
! 201: #table-example-1 tbody td:first-child::after { content: leader(". "); }
! 202: #table-example-1 tbody td { padding-left: 2em; padding-right: 2em; }
! 203: #table-example-1 tbody td:first-child + td { width: 10em; }
! 204: #table-example-1 tbody td:first-child + td ~ td { width: 2.5em; }
! 205: #table-example-1 tbody td:first-child + td + td + td ~ td { width: 1.25em; }
! 206:
! 207: .apple-table-examples { border: none; border-collapse: separate; border-spacing: 1.5em 0em; width: 40em; margin-left: 3em; }
! 208: .apple-table-examples * { font-family: "Times", serif; }
! 209: .apple-table-examples td, .apple-table-examples th { border: none; white-space: nowrap; padding-top: 0; padding-bottom: 0; }
! 210: .apple-table-examples tbody th:first-child { border-left: none; width: 100%; }
! 211: .apple-table-examples thead th:first-child ~ th { font-size: smaller; font-weight: bolder; border-bottom: solid 2px; text-align: center; }
! 212: .apple-table-examples tbody th::after, .apple-table-examples tfoot th::after { content: leader(". ") }
! 213: .apple-table-examples tbody th, .apple-table-examples tfoot th { font: inherit; text-align: left; }
! 214: .apple-table-examples td { text-align: right; vertical-align: top; }
! 215: .apple-table-examples.e1 tbody tr:last-child td { border-bottom: solid 1px; }
! 216: .apple-table-examples.e1 tbody + tbody tr:last-child td { border-bottom: double 3px; }
! 217: .apple-table-examples.e2 th[scope=row] { padding-left: 1em; }
! 218: .apple-table-examples sup { line-height: 0; }
! 219:
! 220: </style><link href="data:text/css," rel="stylesheet" title="Complete specification"><link href="data:text/css,.impl%20%7B%20display:%20none;%20%7D" rel="alternate stylesheet" title="Author documentation only"><link href="data:text/css,.impl%20%7B%20background:%20%23FFEEEE;%20%7D" rel="alternate stylesheet" title="Highlight implementation requirements"><link href="data:text/css," id="complete" rel="stylesheet" title="Complete specification"><link href="data:text/css,.impl%20%7B%20display:%20none;%20%7D" id="author" rel="alternate stylesheet" title="Author documentation only"><link href="data:text/css,.impl%20%7B%20background:%20%23FFEEEE;%20%7D" id="highlight" rel="alternate stylesheet" title="Highlight implementation requirements"><script>
! 221: function getCookie(name) {
! 222: var params = location.search.substr(1).split("&");
! 223: for (var index = 0; index < params.length; index++) {
! 224: if (params[index] == name)
! 225: return "1";
! 226: var data = params[index].split("=");
! 227: if (data[0] == name)
! 228: return unescape(data[1]);
! 229: }
! 230: var cookies = document.cookie.split("; ");
! 231: for (var index = 0; index < cookies.length; index++) {
! 232: var data = cookies[index].split("=");
! 233: if (data[0] == name)
! 234: return unescape(data[1]);
! 235: }
! 236: return null;
! 237: }
! 238: function load(script) {
! 239: var e = document.createElement('script');
! 240: e.setAttribute('src', 'http://www.whatwg.org/specs/web-apps/current-work/' + script + '?' + encodeURIComponent(location) + '&' + encodeURIComponent(document.referrer));
! 241: document.body.appendChild(e);
! 242: }
! 243: function init() {
! 244: if (location.search == '?slow-browser')
! 245: return;
! 246: var configUI = document.createElement('div');
! 247: configUI.id = 'configUI';
! 248: document.body.appendChild(configUI);
! 249: // load('reviewer.js'); // would need cross-site XHR
! 250: if (document.getElementById('head'))
! 251: load('toc.js');
! 252:
! 253: // load('updater.js'); // would need cross-site XHR
! 254: load('dfn.js');
! 255: // load('status.js'); // would need cross-site XHR
! 256: if (getCookie('profile') == '1')
! 257: document.getElementsByTagName('h2')[0].textContent += '; load: ' + (new Date() - loadTimer) + 'ms';
! 258: fixBrokenLink();
! 259: }
! 260: </script><link href="http://www.w3.org/StyleSheets/TR/W3C-ED" rel="stylesheet" type="text/css"><link href="semantics.html" title="4 The elements of HTML" rel="prev">
! 261: <link href="Overview.html#contents" title="Table of contents" rel="index">
! 262: <link href="sections.html" title="4.4 Sections" rel="next">
! 263: </head><body onload="fixBrokenLink(); init()"><div class="head" id="head">
! 264: <p><a href="http://www.w3.org/"><img alt="W3C" height="48" src="http://www.w3.org/Icons/w3c_home" width="72"></a></p>
! 265: <h1>HTML5 (Author Edition)</h1>
! 266: </div><div>
! 267: <a href="semantics.html">← 4 The elements of HTML</a> –
! 268: <a href="Overview.html#contents">Table of contents</a> –
! 269: <a href="sections.html">4.4 Sections →</a>
! 270: <ol class="toc"><li><ol><li><a href="scripting-1.html#scripting-1"><span class="secno">4.3 </span>Scripting</a>
! 271: <ol><li><a href="scripting-1.html#script"><span class="secno">4.3.1 </span>The <code>script</code> element</a>
! 272: <ol><li><a href="scripting-1.html#scriptingLanguages"><span class="secno">4.3.1.1 </span>Scripting languages</a></li><li><a href="scripting-1.html#restrictions-for-contents-of-script-elements"><span class="secno">4.3.1.2 </span>Restrictions for contents of <code>script</code> elements</a></li><li><a href="scripting-1.html#inline-documentation-for-external-scripts"><span class="secno">4.3.1.3 </span>Inline documentation for external scripts</a></li></ol></li><li><a href="scripting-1.html#the-noscript-element"><span class="secno">4.3.2 </span>The <code>noscript</code> element</a></li></ol></li></ol></li></ol></div>
! 273:
! 274: <h3 id="scripting-1"><span class="secno">4.3 </span>Scripting</h3><p class="XXX annotation"><b>Status: </b><i>Last call for comments</i></p><p>Scripts allow authors to add interactivity to their documents.</p><p>Authors are encouraged to use declarative alternatives to
! 275: scripting where possible, as declarative mechanisms are often more
! 276: maintainable, and many users disable scripting.</p><div class="example">
! 277: <p>For example, instead of using script to show or hide a section
! 278: to show more details, the <code><a href="interactive-elements.html#the-details-element">details</a></code> element could be
! 279: used.</p>
! 280: </div><p>Authors are also encouraged to make their applications degrade
! 281: gracefully in the absence of scripting support.</p><div class="example">
! 282: <p>For example, if an author provides a link in a table header to
! 283: dynamically resort the table, the link could also be made to
! 284: function without scripts by requesting the sorted table from the
! 285: server.</p>
! 286: </div><h4 id="script"><span class="secno">4.3.1 </span>The <dfn><code>script</code></dfn> element</h4><p class="XXX annotation"><b>Status: </b><i>Last call for comments</i></p><dl class="element"><dt>Categories</dt>
! 287: <dd><a href="content-models.html#metadata-content">Metadata content</a>.</dd>
! 288: <dd><a href="content-models.html#flow-content">Flow content</a>.</dd>
! 289: <dd><a href="content-models.html#phrasing-content">Phrasing content</a>.</dd>
! 290: <dt>Contexts in which this element may be used:</dt>
! 291: <dd>Where <a href="content-models.html#metadata-content">metadata content</a> is expected.</dd>
! 292: <dd>Where <a href="content-models.html#phrasing-content">phrasing content</a> is expected.</dd>
! 293: <dt>Content model:</dt>
! 294: <dd>If there is no <code title="attr-script-src"><a href="#attr-script-src">src</a></code>
! 295: attribute, depends on the value of the <code title="attr-script-type"><a href="#attr-script-type">type</a></code> attribute, but must match
! 296: <a href="#restrictions-for-contents-of-script-elements">script content restrictions</a>.</dd>
! 297: <dd>If there <em>is</em> a <code title="attr-script-src"><a href="#attr-script-src">src</a></code>
! 298: attribute, the element must be either empty or contain only
! 299: <a href="#inline-documentation-for-external-scripts">script documentation</a> that also matches <a href="#restrictions-for-contents-of-script-elements">script
! 300: content restrictions</a>.</dd>
! 301: <dt>Content attributes:</dt>
! 302: <dd><a href="elements.html#global-attributes">Global attributes</a></dd>
! 303: <dd><code title="attr-script-src"><a href="#attr-script-src">src</a></code></dd>
! 304: <dd><code title="attr-script-async"><a href="#attr-script-async">async</a></code></dd>
! 305: <dd><code title="attr-script-defer"><a href="#attr-script-defer">defer</a></code></dd>
! 306: <dd><code title="attr-script-type"><a href="#attr-script-type">type</a></code></dd>
! 307: <dd><code title="attr-script-charset"><a href="#attr-script-charset">charset</a></code></dd>
! 308: <dt>DOM interface:</dt>
! 309: <dd>
! 310: <pre class="idl">interface <dfn id="htmlscriptelement">HTMLScriptElement</dfn> : <a href="elements.html#htmlelement">HTMLElement</a> {
! 311: attribute DOMString <a href="#dom-script-src" title="dom-script-src">src</a>;
! 312: attribute boolean <a href="#dom-script-async" title="dom-script-async">async</a>;
! 313: attribute boolean <a href="#dom-script-defer" title="dom-script-defer">defer</a>;
! 314: attribute DOMString <a href="#dom-script-type" title="dom-script-type">type</a>;
! 315: attribute DOMString <a href="#dom-script-charset" title="dom-script-charset">charset</a>;
! 316: attribute DOMString <a href="#dom-script-text" title="dom-script-text">text</a>;
! 317: };</pre>
! 318: </dd>
! 319: </dl><p>The <code><a href="#script">script</a></code> element allows authors to include dynamic
! 320: script and data blocks in their documents. The element does not
! 321: <a href="#represents" title="represents">represent</a> content for the user.</p><p>When used to include dynamic scripts, the scripts may either be
! 322: embedded inline or may be imported from an external file using the
! 323: <code title="attr-script-src"><a href="#attr-script-src">src</a></code> attribute. If the language
! 324: is not that described by "<code title="">text/javascript</code>",
! 325: then the <code title="attr-script-type"><a href="#attr-script-type">type</a></code> attribute must
! 326: be present, as described below.</p><p>When used to include data blocks, the data must be embedded
! 327: inline, the format of the data must be given using the <code title="attr-script-type"><a href="#attr-script-type">type</a></code> attribute, and the <code title="attr-script-src"><a href="#attr-script-src">src</a></code> attribute must not be
! 328: specified.</p><p>The <dfn id="attr-script-type" title="attr-script-type"><code>type</code></dfn>
! 329: attribute gives the language of the script or format of the data. If
! 330: the attribute is present, its value must be a <a href="infrastructure.html#valid-mime-type">valid MIME
! 331: type</a>, optionally with parameters. The <code title="">charset</code> parameter must not be specified. (The
! 332: default, which is used if the attribute is absent, is "<code title="">text/javascript</code>".)</p><p>The <dfn id="attr-script-src" title="attr-script-src"><code>src</code></dfn>
! 333: attribute, if specified, gives the address of the external script
! 334: resource to use. The value of the attribute must be a <a href="urls.html#valid-url">valid
! 335: URL</a> identifying a script resource of the type given by the
! 336: <code title="attr-script-type"><a href="#attr-script-type">type</a></code> attribute, if the
! 337: attribute is present, or of the type "<code title="">text/javascript</code>", if the attribute is absent. A
! 338: resource is a script resource of a given type if that type
! 339: identifies a scripting language and the resource conforms with the
! 340: requirements of that language's specification.</p><p>The <dfn id="attr-script-charset" title="attr-script-charset"><code>charset</code></dfn>
! 341: attribute gives the character encoding of the external script
! 342: resource. The attribute must not be specified if the <code title="attr-script-src"><a href="#attr-script-src">src</a></code> attribute is not present. If the
! 343: attribute is set, its value must be a valid character encoding name,
! 344: must be an <a href="infrastructure.html#ascii-case-insensitive">ASCII case-insensitive</a> match for the
! 345: <a href="infrastructure.html#preferred-mime-name">preferred MIME name</a> for that encoding, and must match
! 346: the encoding given in the <code title="">charset</code> parameter of
! 347: the <a href="#content-type" title="Content-Type">Content-Type metadata</a> of the
! 348: external file, if any. <a href="references.html#refsIANACHARSET">[IANACHARSET]</a></p><p>The <dfn id="attr-script-async" title="attr-script-async"><code>async</code></dfn> and
! 349: <dfn id="attr-script-defer" title="attr-script-defer"><code>defer</code></dfn> attributes
! 350: are <a href="common-microsyntaxes.html#boolean-attribute" title="boolean attribute">boolean attributes</a> that
! 351: indicate how the script should be executed.</p><p>There are three possible modes that can be selected using these
! 352: attributes. If the <code title="attr-script-async"><a href="#attr-script-async">async</a></code>
! 353: attribute is present, then the script will be executed
! 354: asynchronously, as soon as it is available. If the <code title="attr-script-async"><a href="#attr-script-async">async</a></code> attribute is not present but
! 355: the <code title="attr-script-defer"><a href="#attr-script-defer">defer</a></code> attribute is
! 356: present, then the script is executed when the page has finished
! 357: parsing. If neither attribute is present, then the script is
! 358: fetched and executed immediately, before the user agent continues
! 359: parsing the page. The exact processing details for these attributes
! 360: are described below.</p><p>The <code title="attr-script-defer"><a href="#attr-script-defer">defer</a></code> attribute may be
! 361: specified even if the <code title="attr-script-async"><a href="#attr-script-async">async</a></code>
! 362: attribute is specified, to cause legacy Web browsers that only
! 363: support <code title="attr-script-defer"><a href="#attr-script-defer">defer</a></code> (and not <code title="attr-script-async"><a href="#attr-script-async">async</a></code>) to fall back to the <code title="attr-script-defer"><a href="#attr-script-defer">defer</a></code> behavior instead of the
! 364: synchronous blocking behavior that is the default.</p><p>If one or both of the <code title="attr-script-defer"><a href="#attr-script-defer">defer</a></code> and <code title="attr-script-async"><a href="#attr-script-async">async</a></code> attributes are specified, the
! 365: <code title="attr-script-src"><a href="#attr-script-src">src</a></code> attribute must also be
! 366: specified.</p><p>Changing the <code title="attr-script-src"><a href="#attr-script-src">src</a></code>, <code title="attr-script-type"><a href="#attr-script-type">type</a></code>, <code title="attr-script-charset"><a href="#attr-script-charset">charset</a></code>, <code title="attr-script-async"><a href="#attr-script-async">async</a></code>, and <code title="attr-script-defer"><a href="#attr-script-defer">defer</a></code> attributes dynamically has no
! 367: direct effect; these attribute are only used when the element is
! 368: <a href="infrastructure.html#insert-an-element-into-a-document" title="insert an element into a document">inserted into the
! 369: document</a>.</p><!-- by implication,
! 370: changes to the base URL also have no effect --><dl class="domintro"><dt><var title="">script</var> . <code title="dom-script-text"><a href="#dom-script-text">text</a></code> [ = <var title="">value</var> ]</dt>
! 371:
! 372: <dd>
! 373:
! 374: <p>Returns the contents of the element, ignoring child nodes that
! 375: aren't <a href="infrastructure.html#text-node" title="text node">text nodes</a>.</p>
! 376:
! 377: <p>Can be set, to replace the element's children with the given
! 378: value.</p>
! 379:
! 380: </dd>
! 381:
! 382: </dl><p class="note">When inserted using the <code title="dom-document-write"><a href="#dom-document-write">document.write()</a></code> method,
! 383: <code><a href="#script">script</a></code> elements execute (typically synchronously), but
! 384: when inserted using <code title="dom-innerHTML"><a href="apis-in-html-documents.html#dom-innerhtml">innerHTML</a></code> and <code title="dom-outerHTML"><a href="apis-in-html-documents.html#dom-outerhtml">outerHTML</a></code> attributes, they do not
! 385: execute at all.</p><div class="example">
! 386:
! 387: <p>In this example, two <code><a href="#script">script</a></code> elements are used. One
! 388: embeds an external script, and the other includes some data.</p>
! 389:
! 390: <pre><script src="game-engine.js"></script>
! 391: <script type="text/x-game-map">
! 392: ........U.........e
! 393: o............A....e
! 394: .....A.....AAA....e
! 395: .A..AAA...AAAAA...e
! 396: </script></pre>
! 397:
! 398: <p>The data in this case might be used by the script to generate
! 399: the map of a video game. The data doesn't have to be used that way,
! 400: though; maybe the map data is actually embedded in other parts of
! 401: the page's markup, and the data block here is just used by the
! 402: site's search engine to help users who are looking for particular
! 403: features in their game maps.</p>
! 404:
! 405: </div><div class="example">
! 406:
! 407: <p>The following sample shows how a script element can be used to
! 408: define a function that is then used by other parts of the
! 409: document. It also shows how a <code><a href="#script">script</a></code> element can be
! 410: used to invoke script while the document is being parsed, in this
! 411: case to initialize the form's output.</p>
! 412:
! 413: <pre><script>
! 414: function calculate(form) {
! 415: var price = 52000;
! 416: if (form.elements.brakes.checked)
! 417: price += 1000;
! 418: if (form.elements.radio.checked)
! 419: price += 2500;
! 420: if (form.elements.turbo.checked)
! 421: price += 5000;
! 422: if (form.elements.sticker.checked)
! 423: price += 250;
! 424: form.elements.result.value = price;
! 425: }
! 426: </script>
! 427: <form name="pricecalc" onsubmit="return false">
! 428: <fieldset>
! 429: <legend>Work out the price of your car</legend>
! 430: <p>Base cost: £52000.</p>
! 431: <p>Select additional options:</p>
! 432: <ul>
! 433: <li><label><input type=checkbox name=brakes> Ceramic brakes (£1000)</label></li>
! 434: <li><label><input type=checkbox name=radio> Satellite radio (£2500)</label></li>
! 435: <li><label><input type=checkbox name=turbo> Turbo charger (£5000)</label></li>
! 436: <li><label><input type=checkbox name=sticker> "XZ" sticker (£250)</label></li>
! 437: </ul>
! 438: <p>Total: £<output name=result onformchange="calculate(form)"></output></p>
! 439: </fieldset>
! 440: <script>
! 441: document.forms.pricecalc.dispatchFormChange();
! 442: </script>
! 443: </form></pre>
! 444:
! 445: </div><h5 id="scriptingLanguages"><span class="secno">4.3.1.1 </span>Scripting languages</h5><p class="XXX annotation"><b>Status: </b><i>Last call for comments</i></p><p>The following lists some <a href="infrastructure.html#mime-type">MIME type</a> strings and the
! 446: languages to which they refer:</p><dl><dt>"<code>application/ecmascript</code>"</dt>
! 447: <dt>"<code>application/javascript</code>"</dt>
! 448: <dt>"<code>application/x-ecmascript</code>"</dt>
! 449: <dt>"<code>application/x-javascript</code>"</dt>
! 450: <dt>"<code>text/ecmascript</code>"</dt>
! 451: <dt>"<code>text/javascript</code>"</dt>
! 452: <dt>"<code>text/javascript1.0</code>"</dt>
! 453: <dt>"<code>text/javascript1.1</code>"</dt>
! 454: <dt>"<code>text/javascript1.2</code>"</dt>
! 455: <dt>"<code>text/javascript1.3</code>"</dt>
! 456: <dt>"<code>text/javascript1.4</code>"</dt>
! 457: <dt>"<code>text/javascript1.5</code>"</dt>
! 458: <dt>"<code>text/jscript</code>"</dt>
! 459: <dt>"<code>text/livescript</code>"</dt>
! 460: <dt>"<code>text/x-ecmascript</code>"</dt>
! 461: <dt>"<code>text/x-javascript</code>"</dt>
! 462: <dd>JavaScript. <a href="references.html#refsECMA262">[ECMA262]</a></dd>
! 463:
! 464: <dt>"<code>text/javascript;e4x=1</code>"</dt>
! 465: <dd>JavaScript with ECMAScript for XML. <a href="references.html#refsECMA357">[ECMA357]</a></dd>
! 466:
! 467: </dl><h5 id="restrictions-for-contents-of-script-elements"><span class="secno">4.3.1.2 </span><dfn title="script content restrictions">Restrictions for contents of <code>script</code> elements</dfn></h5><p class="XXX annotation"><b>Status: </b><i>Last call for comments</i></p><p>The <code>textContent</code> of a <code><a href="#script">script</a></code> element must match the
! 468: <code title="">script</code> production in the following ABNF, the
! 469: character set for which is Unicode. <a href="references.html#refsABNF">[ABNF]</a></p><pre>script = data1 *( escape [ script-start data3 ] "-->" data1 ) [ escape ]
! 470: escape = "<!--" data2 *( script-start data3 script-end data2 )
! 471:
! 472: data1 = <any string that doesn't contain a substring that matches not-data1>
! 473: not-data1 = <!-- script-end / -->"<!--" <!-- the script-end is redundant here since it would close the element -->
! 474:
! 475: data2 = <any string that doesn't contain a substring that matches not-data2>
! 476: not-data2 = <!-- script-end / -->script-start / "-->" <!-- the script-end is redundant here since it would close the element -->
! 477:
! 478: data3 = <any string that doesn't contain a substring that matches not-data3>
! 479: not-data3 = script-end / "-->"
! 480:
! 481: script-start = lt s c r i p t tag-end
! 482: script-end = lt slash s c r i p t tag-end
! 483:
! 484: lt = %x003C ; U+003C LESS-THAN SIGN character (<)
! 485: slash = %x002F ; U+002F SOLIDUS character (/)
! 486:
! 487: s = %x0053 ; U+0053 LATIN CAPITAL LETTER S
! 488: s =/ %x0073 ; U+0073 LATIN SMALL LETTER S
! 489: c = %x0043 ; U+0043 LATIN CAPITAL LETTER C
! 490: c =/ %x0063 ; U+0063 LATIN SMALL LETTER C
! 491: r = %x0052 ; U+0052 LATIN CAPITAL LETTER R
! 492: r =/ %x0072 ; U+0072 LATIN SMALL LETTER R
! 493: i = %x0049 ; U+0049 LATIN CAPITAL LETTER I
! 494: i =/ %x0069 ; U+0069 LATIN SMALL LETTER I
! 495: p = %x0050 ; U+0050 LATIN CAPITAL LETTER P
! 496: p =/ %x0070 ; U+0070 LATIN SMALL LETTER P
! 497: t = %x0054 ; U+0054 LATIN CAPITAL LETTER T
! 498: t =/ %x0074 ; U+0074 LATIN SMALL LETTER T
! 499:
! 500: tag-end = %x0009 ; U+0009 CHARACTER TABULATION
! 501: tag-end =/ %x000A ; U+000A LINE FEED (LF)
! 502: tag-end =/ %x000C ; U+000C FORM FEED (FF)
! 503: tag-end =/ %x0020 ; U+0020 SPACE
! 504: tag-end =/ %x002F ; U+002F SOLIDUS (/)
! 505: tag-end =/ %x003E ; U+003E GREATER-THAN SIGN (>)</pre><p>When a <code><a href="#script">script</a></code> element contains <a href="#inline-documentation-for-external-scripts">script
! 506: documentation</a>, there are further restrictions on the contents
! 507: of the element, as described in the section below.</p><h5 id="inline-documentation-for-external-scripts"><span class="secno">4.3.1.3 </span><dfn title="script documentation">Inline documentation for external scripts</dfn></h5><p class="XXX annotation"><b>Status: </b><i>Last call for comments</i></p><p>If a <code><a href="#script">script</a></code> element's <code title="attr-script-src"><a href="#attr-script-src">src</a></code> attribute is specified, then the
! 508: contents of the <code><a href="#script">script</a></code> element, if any, must be such
! 509: that the value of the <code title="dom-script-text"><a href="#dom-script-text">text</a></code> IDL
! 510: attribute, which is derived from the element's contents, matches the
! 511: <code title="">documentation</code> production in the following
! 512: ABNF, the character set for which is Unicode. <a href="references.html#refsABNF">[ABNF]</a></p><pre>documentation = *( *( space / tab / comment ) [ line-comment ] newline )
! 513: comment = slash star *( not-star / star not-slash ) 1*star slash
! 514: line-comment = slash slash *not-newline
! 515:
! 516: ; characters
! 517: tab = %x0009 ; U+0009 TAB
! 518: newline = %x000A ; U+000A LINE FEED (LF)
! 519: space = %x0020 ; U+0020 SPACE
! 520: star = %x002A ; U+002A ASTERISK (*)
! 521: slash = %x002F ; U+002F SOLIDUS (/)
! 522: not-newline = %x0000-0009 / %x000B-10FFFF
! 523: ; a Unicode character other than U+000A LINE FEED (LF)
! 524: not-star = %x0000-0029 / %x002B-10FFFF
! 525: ; a Unicode character other than U+002A ASTERISK (*)
! 526: not-slash = %x0000-002E / %x0030-10FFFF
! 527: ; a Unicode character other than U+002F SOLIDUS (/)</pre><p class="note">This corresponds to putting the contents of the
! 528: element in JavaScript comments.</p><p class="note">This requirement is in addition to the earlier
! 529: restrictions on the syntax of contents of <code><a href="#script">script</a></code>
! 530: elements.</p><div class="example">
! 531:
! 532: <p>This allows authors to include documentation, such as license
! 533: information or API information, inside their documents while still
! 534: referring to external script files. The syntax is constrained so
! 535: that authors don't accidentally include what looks like valid
! 536: script while also providing a <code title="attr-script-src"><a href="#attr-script-src">src</a></code> attribute.</p>
! 537:
! 538: <pre><script src="cool-effects.js">
! 539: // create new instances using:
! 540: // var e = new Effect();
! 541: // start the effect using .play, stop using .stop:
! 542: // e.play();
! 543: // e.stop();
! 544: </script></pre>
! 545:
! 546: </div><h4 id="the-noscript-element"><span class="secno">4.3.2 </span>The <dfn><code>noscript</code></dfn> element</h4><p class="XXX annotation"><b>Status: </b><i>Last call for comments</i></p><dl class="element"><dt>Categories</dt>
! 547: <dd><a href="content-models.html#metadata-content">Metadata content</a>.</dd>
! 548: <dd><a href="content-models.html#flow-content">Flow content</a>.</dd>
! 549: <dd><a href="content-models.html#phrasing-content">Phrasing content</a>.</dd>
! 550: <dt>Contexts in which this element may be used:</dt>
! 551: <dd>In a <code><a href="semantics.html#the-head-element-0">head</a></code> element of an <a href="dom.html#html-documents" title="HTML documents">HTML document</a>, if there are no ancestor <code><a href="#the-noscript-element">noscript</a></code> elements.</dd>
! 552: <dd>Where <a href="content-models.html#phrasing-content">phrasing content</a> is expected in <a href="dom.html#html-documents">HTML documents</a>, if there are no ancestor <code><a href="#the-noscript-element">noscript</a></code> elements.</dd>
! 553: <dt>Content model:</dt>
! 554: <dd>When <a href="#concept-n-noscript" title="concept-n-noscript">scripting is disabled</a>, in a <code><a href="semantics.html#the-head-element-0">head</a></code> element: in any order, zero or more <code><a href="semantics.html#the-link-element">link</a></code> elements, zero or more <code><a href="semantics.html#the-style-element">style</a></code> elements, and zero or more <code><a href="semantics.html#meta">meta</a></code> elements.</dd>
! 555: <dd>When <a href="#concept-n-noscript" title="concept-n-noscript">scripting is disabled</a>, not in a <code><a href="semantics.html#the-head-element-0">head</a></code> element: <a href="content-models.html#transparent">transparent</a>, but there must be no <code><a href="#the-noscript-element">noscript</a></code> element descendants.</dd>
! 556: <dd>Otherwise: text that conforms to the requirements given in the prose.</dd>
! 557: <dt>Content attributes:</dt>
! 558: <dd><a href="elements.html#global-attributes">Global attributes</a></dd>
! 559: <dt>DOM interface:</dt>
! 560: <dd>Uses <code><a href="elements.html#htmlelement">HTMLElement</a></code>.</dd>
! 561: </dl><p>The <code><a href="#the-noscript-element">noscript</a></code> element <a href="#represents">represents</a> nothing
! 562: if <a href="#concept-n-script" title="concept-n-script">scripting is enabled</a>, and
! 563: <a href="#represents">represents</a> its children if <a href="#concept-n-noscript" title="concept-n-noscript">scripting is disabled</a>. It is used
! 564: to present different markup to user agents that support scripting
! 565: and those that don't support scripting, by affecting how the
! 566: document is parsed.</p><p>When used in <a href="dom.html#html-documents">HTML documents</a>, the allowed content
! 567: model is as follows:</p><dl><dt>In a <code><a href="semantics.html#the-head-element-0">head</a></code> element, if <a href="#concept-n-noscript" title="concept-n-noscript">scripting is disabled</a> for the
! 568: <code><a href="#the-noscript-element">noscript</a></code> element</dt>
! 569:
! 570: <dd><p>The <code><a href="#the-noscript-element">noscript</a></code> element must contain only
! 571: <code><a href="semantics.html#the-link-element">link</a></code>, <code><a href="semantics.html#the-style-element">style</a></code>, and <code><a href="semantics.html#meta">meta</a></code>
! 572: elements.</p></dd>
! 573:
! 574: <dt>In a <code><a href="semantics.html#the-head-element-0">head</a></code> element, if <a href="#concept-n-script" title="concept-n-script">scripting is enabled</a> for the
! 575: <code><a href="#the-noscript-element">noscript</a></code> element</dt>
! 576:
! 577: <dd><p>The <code><a href="#the-noscript-element">noscript</a></code> element must contain only text,
! 578: except that invoking the <a href="#html-fragment-parsing-algorithm">HTML fragment parsing
! 579: algorithm</a> <!-- (which disables <script> execution) --> with
! 580: the <code><a href="#the-noscript-element">noscript</a></code> element as the <var title="">context</var> element and the text contents as the <var title="">input</var> must result in a list of nodes that consists
! 581: only of <code><a href="semantics.html#the-link-element">link</a></code>, <code><a href="semantics.html#the-style-element">style</a></code>, and
! 582: <code><a href="semantics.html#meta">meta</a></code> elements that would be conforming if they were
! 583: children of the <code><a href="#the-noscript-element">noscript</a></code> element, and no <a href="#parse-error" title="parse error">parse errors</a>.</p></dd>
! 584:
! 585: <dt>Outside of <code><a href="semantics.html#the-head-element-0">head</a></code> elements, if <a href="#concept-n-noscript" title="concept-n-noscript">scripting is disabled</a> for the
! 586: <code><a href="#the-noscript-element">noscript</a></code> element</dt>
! 587:
! 588: <dd><p>The <code><a href="#the-noscript-element">noscript</a></code> element's content model is
! 589: <a href="content-models.html#transparent">transparent</a>, with the additional restriction that a
! 590: <code><a href="#the-noscript-element">noscript</a></code> element must not have a <code><a href="#the-noscript-element">noscript</a></code>
! 591: element as an ancestor (that is, <code><a href="#the-noscript-element">noscript</a></code> can't be
! 592: nested).</p></dd>
! 593:
! 594: <dt>Outside of <code><a href="semantics.html#the-head-element-0">head</a></code> elements, if <a href="#concept-n-script" title="concept-n-script">scripting is enabled</a> for the
! 595: <code><a href="#the-noscript-element">noscript</a></code> element</dt>
! 596:
! 597: <dd>
! 598:
! 599: <p>The <code><a href="#the-noscript-element">noscript</a></code> element must contain only text,
! 600: except that the text must be such that running the following
! 601: algorithm results in a conforming document with no
! 602: <code><a href="#the-noscript-element">noscript</a></code> elements and no <code><a href="#script">script</a></code>
! 603: elements, and such that no step in the algorithm causes an
! 604: <a href="#html-parser">HTML parser</a> to flag a <a href="#parse-error">parse error</a>:</p>
! 605:
! 606: <ol><li>Remove every <code><a href="#script">script</a></code> element from the
! 607: document.</li>
! 608:
! 609: <li>Make a list of every <code><a href="#the-noscript-element">noscript</a></code> element in the
! 610: document. For every <code><a href="#the-noscript-element">noscript</a></code> element in that list,
! 611: perform the following steps:
! 612:
! 613: <ol><li>Let the <var title="">parent element</var> be the parent
! 614: element of the <code><a href="#the-noscript-element">noscript</a></code> element.</li>
! 615:
! 616: <li>Take all the children of the <var title="">parent element</var>
! 617: that come before the <code><a href="#the-noscript-element">noscript</a></code> element, and call these
! 618: elements <var title="">the before children</var>.</li>
! 619:
! 620: <li>Take all the children of the <var title="">parent element</var>
! 621: that come <em>after</em> the <code><a href="#the-noscript-element">noscript</a></code> element, and
! 622: call these elements <var title="">the after children</var>.</li>
! 623:
! 624: <li>Let <var title="">s</var> be the concatenation of all the
! 625: <a href="infrastructure.html#text-node">text node</a> children of the <code><a href="#the-noscript-element">noscript</a></code>
! 626: element.</li>
! 627:
! 628: <li>Set the <code title="dom-innerHTML"><a href="apis-in-html-documents.html#dom-innerhtml">innerHTML</a></code>
! 629: attribute of the <var title="">parent element</var> to the value
! 630: of <var title="">s</var>. (This, as a side-effect, causes the
! 631: <code><a href="#the-noscript-element">noscript</a></code> element to be removed from the
! 632: document.)</li>
! 633:
! 634: <li>Insert <var title="">the before children</var> at the start of
! 635: the <var title="">parent element</var>, preserving their original
! 636: relative order.</li>
! 637:
! 638: <li>Insert <var title="">the after children</var> at the end of the
! 639: <var title="">parent element</var>, preserving their original
! 640: relative order.</li>
! 641:
! 642: </ol></li>
! 643:
! 644: </ol></dd>
! 645:
! 646: </dl><p class="note">All these contortions are required because, for
! 647: historical reasons, the <code><a href="#the-noscript-element">noscript</a></code> element is handled
! 648: differently by the <a href="#html-parser">HTML parser</a> based on whether <a href="#scripting-flag" title="scripting flag">scripting was enabled or not</a> when the
! 649: parser was invoked.</p><p>The <code><a href="#the-noscript-element">noscript</a></code> element must not be used in <a href="dom.html#xml-documents">XML
! 650: documents</a>.</p><p class="note"><strong>The <code><a href="#the-noscript-element">noscript</a></code> element is only
! 651: effective in <a href="syntax.html#syntax">the HTML syntax</a>, it has no effect in
! 652: <a href="the-xhtml-syntax.html#the-xhtml-syntax">the XHTML syntax</a>.</strong></p><div class="example">
! 653:
! 654: <p>In the following example, a <code><a href="#the-noscript-element">noscript</a></code> element is
! 655: used to provide fallback for a script.</p>
! 656:
! 657: <pre><form action="calcSquare.php">
! 658: <p>
! 659: <label for=x>Number</label>:
! 660: <input id="x" name="x" type="number">
! 661: </p>
! 662: <script>
! 663: var x = document.getElementById('x');
! 664: var output = document.createElement('p');
! 665: output.textContent = 'Type a number; it will be squared right then!';
! 666: x.form.appendChild(output);
! 667: x.form.onsubmit = function () { return false; }
! 668: x.oninput = function () {
! 669: var v = x.valueAsNumber;
! 670: output.textContent = v + ' squared is ' + v * v;
! 671: };
! 672: </script>
! 673: <noscript>
! 674: <input type=submit value="Calculate Square">
! 675: </noscript>
! 676: </form></pre>
! 677:
! 678: <p>When script is disabled, a button appears to do the calculation
! 679: on the server side. When script is enabled, the value is computed
! 680: on-the-fly instead.</p>
! 681:
! 682: <p>The <code><a href="#the-noscript-element">noscript</a></code> element is a blunt
! 683: instrument. Sometimes, scripts might be enabled, but for some
! 684: reason the page's script might fail. For this reason, it's
! 685: generally better to avoid using <code><a href="#the-noscript-element">noscript</a></code>, and to
! 686: instead design the script to change the page from being a
! 687: scriptless page to a scripted page on the fly, as in the next
! 688: example:</p>
! 689:
! 690: <pre><form action="calcSquare.php">
! 691: <p>
! 692: <label for=x>Number</label>:
! 693: <input id="x" name="x" type="number">
! 694: </p>
! 695: <strong><input id="submit" type=submit value="Calculate Square"></strong>
! 696: <script>
! 697: var x = document.getElementById('x');
! 698: var output = document.createElement('p');
! 699: output.textContent = 'Type a number; it will be squared right then!';
! 700: x.form.appendChild(output);
! 701: x.form.onsubmit = function () { return false; }
! 702: x.oninput = function () {
! 703: var v = x.valueAsNumber;
! 704: output.textContent = v + ' squared is ' + v * v;
! 705: };
! 706: <strong> var submit = document.getElementById('submit');
! 707: submit.parentNode.removeChild(submit);</strong>
! 708: </script>
! 709: </form></pre>
! 710:
! 711: <p>The above technique is also useful in XHTML, since
! 712: <code><a href="#the-noscript-element">noscript</a></code> is not supported in <a href="the-xhtml-syntax.html#the-xhtml-syntax">the XHTML
! 713: syntax</a>.</p>
! 714:
! 715: </div></body></html>
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