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  <title>P2958R0: typeof and typeof_unqual for C++</title>
<style data-fill-with="stylesheet">/******************************************************************************
 *                   Style sheet for the W3C specifications                   *
 *
 * Special classes handled by this style sheet include:
 *
 * Indices
 *   - .toc for the Table of Contents (<ol class="toc">)
 *     + <span class="secno"> for the section numbers
 *   - #toc for the Table of Contents (<nav id="toc">)
 *   - ul.index for Indices (<a href="#ref">term</a><span>, in § N.M</span>)
 *   - table.index for Index Tables (e.g. for properties or elements)
 *
 * Structural Markup
 *   - table.data for general data tables
 *     -> use 'scope' attribute, <colgroup>, <thead>, and <tbody> for best results !
 *     -> use <table class='complex data'> for extra-complex tables
 *     -> use <td class='long'> for paragraph-length cell content
 *     -> use <td class='pre'> when manual line breaks/indentation would help readability
 *   - dl.switch for switch statements
 *   - ol.algorithm for algorithms (helps to visualize nesting)
 *   - .figure and .caption (HTML4) and figure and figcaption (HTML5)
 *     -> .sidefigure for right-floated figures
 *   - ins/del
 *     -> ins/del.c### for candidate and proposed changes (amendments)
 *
 * Code
 *   - pre and code
 *
 * Special Sections
 *   - .note       for informative notes             (div, p, span, aside, details)
 *   - .example    for informative examples          (div, p, pre, span)
 *   - .issue      for issues                        (div, p, span)
 *   - .advisement for loud normative statements     (div, p, strong)
 *   - .annoying-warning for spec obsoletion notices (div, aside, details)
 *   - .correction for "candidate corrections"       (div, aside, details, section)
 *   - .addition   for "candidate additions"         (div, aside, details, section)
 *   - .correction.proposed for "proposed corrections" (div, aside, details, section)
 *   - .addition.proposed   for "proposed additions"   (div, aside, details, section)
 *
 * Definition Boxes
 *   - pre.def   for WebIDL definitions
 *   - table.def for tables that define other entities (e.g. CSS properties)
 *   - dl.def    for definition lists that define other entitles (e.g. HTML elements)
 *
 * Numbering
 *   - .secno for section numbers in .toc and headings (<span class='secno'>3.2</span>)
 *   - .marker for source-inserted example/figure/issue numbers (<span class='marker'>Issue 4</span>)
 *   - ::before styled for CSS-generated issue/example/figure numbers:
 *     -> Documents wishing to use this only need to add
 *        figcaption::before,
 *        .caption::before { content: "Figure "  counter(figure) " ";  }
 *        .example::before { content: "Example " counter(example) " "; }
 *        .issue::before   { content: "Issue "   counter(issue) " ";   }
 *
 * Header Stuff (ignore, just don't conflict with these classes)
 *   - .head for the header
 *   - .copyright for the copyright
 *
 * Outdated warning for old specs
 *
 * Miscellaneous
 *   - .overlarge for things that should be as wide as possible, even if
 *     that overflows the body text area. This can be used on an item or
 *     on its container, depending on the effect desired.
 *     Note that this styling basically doesn't help at all when printing,
 *     since A4 paper isn't much wider than the max-width here.
 *     It's better to design things to fit into a narrower measure if possible.
 *
 *   - js-added ToC jump links (see fixup.js)
 *
 ******************************************************************************/

/* color variables included separately for reliability */

/******************************************************************************/
/*                                    Body                                    */
/******************************************************************************/

	html {
	}

	body {
		counter-reset: example figure issue;

		/* Layout */
		max-width: 50em;			  /* limit line length to 50em for readability   */
		margin: 0 auto;				/* center text within page                    */
		padding: 1.6em 1.5em 2em 50px; /* assume 16px font size for downlevel clients */
		padding: 1.6em 1.5em 2em calc(26px + 1.5em); /* leave space for status flag    */

		/* Typography */
		line-height: 1.5;
		font-family: sans-serif;
		widows: 2;
		orphans: 2;
		word-wrap: break-word;
		overflow-wrap: break-word;
		hyphens: auto;

		color: black;
		color: var(--text);
		background: white top left fixed no-repeat;
		background: var(--bg) top left fixed no-repeat;
		background-size: 25px auto;
	}


/******************************************************************************/
/*                         Front Matter & Navigation                          */
/******************************************************************************/

/** Header ********************************************************************/

	div.head { margin-bottom: 1em; }
	div.head hr { border-style: solid; }

	div.head h1 {
		font-weight: bold;
		margin: 0 0 .1em;
		font-size: 220%;
	}

	div.head h2 { margin-bottom: 1.5em;}

/** W3C Logo ******************************************************************/

	.head .logo {
		float: right;
		margin: 0.4rem 0 0.2rem .4rem;
	}

	.head img[src*="logos/W3C"] {
		display: block;
		border: solid #1a5e9a;
		border: solid var(--logo-bg);
		border-width: .65rem .7rem .6rem;
		border-radius: .4rem;
		background: #1a5e9a;
		background: var(--logo-bg);
		color: white;
		color: var(--logo-text);
		font-weight: bold;
	}

	.head a:hover > img[src*="logos/W3C"],
	.head a:focus > img[src*="logos/W3C"] {
		opacity: .8;
	}

	.head a:active > img[src*="logos/W3C"] {
		background: #c00;
		background: var(--logo-active-bg);
		border-color: #c00;
		border-color: var(--logo-active-bg);
	}

	/* see also additional rules in Link Styling section */

/** Copyright *****************************************************************/

	p.copyright,
	p.copyright small { font-size: small; }

/** Back to Top / ToC Toggle **************************************************/

	@media print {
		#toc-nav {
			display: none;
		}
	}
	@media not print {
		#toc-nav {
			position: fixed;
			z-index: 3;
			bottom: 0; left: 0;
			margin: 0;
			min-width: 1.33em;
			border-top-right-radius: 2rem;
			box-shadow: 0 0 2px;
			font-size: 1.5em;
		}
		#toc-nav > a {
			display: block;
			white-space: nowrap;

			height: 1.33em;
			padding: .1em 0.3em;
			margin: 0;

			box-shadow: 0 0 2px;
			border: none;
			border-top-right-radius: 1.33em;

			color: #707070;
			color: var(--tocnav-normal-text);
			background: white;
			background: var(--tocnav-normal-bg);
		}
		#toc-nav > a:hover,
		#toc-nav > a:focus {
			color: black;
			color: var(--tocnav-hover-text);
			background: #f8f8f8;
			background: var(--tocnav-hover-bg);
		}
		#toc-nav > a:active {
			color: #c00;
			color: var(--tocnav-active-text);
			background: white;
			background: var(--tocnav-active-bg);
		}

		#toc-nav > #toc-jump {
			padding-bottom: 2em;
			margin-bottom: -1.9em;
		}

		/* statusbar gets in the way on keyboard focus; remove once browsers fix */
		#toc-nav > a[href="#toc"]:not(:hover):focus:last-child {
			padding-bottom: 1.5rem;
		}

		#toc-nav:not(:hover) > a:not(:focus) > span + span {
			/* Ideally this uses :focus-within on #toc-nav */
			display: none;
		}
		#toc-nav > a > span + span {
			padding-right: 0.2em;
		}
	}

/** ToC Sidebar ***************************************************************/

	/* Floating sidebar */
	@media screen {
		body.toc-sidebar #toc {
			position: fixed;
			top: 0; bottom: 0;
			left: 0;
			width: 23.5em;
			max-width: 80%;
			max-width: calc(100% - 2em - 26px);
			overflow: auto;
			padding: 0 1em;
			padding-left: 42px;
			padding-left: calc(1em + 26px);
			color: black;
			color: var(--tocsidebar-text);
			background: inherit;
			background-color: #f7f8f9;
			background-color: var(--tocsidebar-bg);
			z-index: 1;
			box-shadow: -.1em 0 .25em rgba(0,0,0,.1) inset;
			box-shadow: -.1em 0 .25em var(--tocsidebar-shadow) inset;
		}
		body.toc-sidebar #toc h2 {
			margin-top: .8rem;
			font-variant: small-caps;
			font-variant: all-small-caps;
			text-transform: lowercase;
			font-weight: bold;
			color: gray;
			color: hsla(203,20%,40%,.7);
			color: var(--tocsidebar-heading-text);
		}
		body.toc-sidebar #toc-jump:not(:focus) {
			width: 0;
			height: 0;
			padding: 0;
			position: absolute;
			overflow: hidden;
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	}
	/* Hide main scroller when only the ToC is visible anyway */
	@media screen and (max-width: 28em) {
		body.toc-sidebar {
			overflow: hidden;
		}
	}

	/* Sidebar with its own space */
	@media screen and (min-width: 78em) {
		body:not(.toc-inline) #toc {
			position: fixed;
			top: 0; bottom: 0;
			left: 0;
			width: 23.5em;
			overflow: auto;
			padding: 0 1em;
			padding-left: 42px;
			padding-left: calc(1em + 26px);
			color: black;
			color: var(--tocsidebar-text);
			background: inherit;
			background-color: #f7f8f9;
			background-color: var(--tocsidebar-bg);
			z-index: 1;
			box-shadow: -.1em 0 .25em rgba(0,0,0,.1) inset;
			box-shadow: -.1em 0 .25em var(--tocsidebar-shadow) inset;
		}
		body:not(.toc-inline) #toc h2 {
			margin-top: .8rem;
			font-variant: small-caps;
			font-variant: all-small-caps;
			text-transform: lowercase;
			font-weight: bold;
			color: gray;
			color: hsla(203,20%,40%,.7);
			color: var(--tocsidebar-heading-text);
		}

		body:not(.toc-inline) {
			padding-left: 29em;
		}
		/* See also Overflow section at the bottom */

		body:not(.toc-inline) #toc-jump:not(:focus) {
			width: 0;
			height: 0;
			padding: 0;
			position: absolute;
			overflow: hidden;
		}
	}
	@media screen and (min-width: 90em) {
		body:not(.toc-inline) {
			margin: 0 4em;
		}
	}

/******************************************************************************/
/*                                Sectioning                                  */
/******************************************************************************/

/** Headings ******************************************************************/

	h1, h2, h3, h4, h5, h6, dt {
		page-break-after: avoid;
		page-break-inside: avoid;
		font: 100% sans-serif;   /* Reset all font styling to clear out UA styles */
		font-family: inherit;	/* Inherit the font family. */
		line-height: 1.2;		/* Keep wrapped headings compact */
		hyphens: manual;		/* Hyphenated headings look weird */
	}

	h2, h3, h4, h5, h6 {
		margin-top: 3rem;
	}

	h1, h2, h3 {
		color: #005A9C;
		color: var(--heading-text);
	}

	h1 { font-size: 170%; }
	h2 { font-size: 140%; }
	h3 { font-size: 120%; }
	h4 { font-weight: bold; }
	h5 { font-style: italic; }
	h6 { font-variant: small-caps; }
	dt { font-weight: bold; }

/** Subheadings ***************************************************************/

	h1 + h2,
	#profile-and-date {
		/* #profile-and-date is a subtitle in an H2 under the H1 */
		margin-top: 0;
	}
	h2 + h3,
	h3 + h4,
	h4 + h5,
	h5 + h6 {
		margin-top: 1.2em; /* = 1 x line-height */
	}

/** Section divider ***********************************************************/

	:not(.head) > :not(.head) + hr {
		font-size: 1.5em;
		text-align: center;
		margin: 1em auto;
		height: auto;
		color: black;
		color: var(--hr-text);
		border: transparent solid 0;
		background: transparent;
	}
	:not(.head) > hr::before {
		content: "\2727\2003\2003\2727\2003\2003\2727";
	}

/******************************************************************************/
/*                            Paragraphs and Lists                            */
/******************************************************************************/

	p {
		margin: 1em 0;
	}

	dd > p:first-child,
	li > p:first-child {
		margin-top: 0;
	}

	ul, ol {
		margin-left: 0;
		padding-left: 2em;
	}

	li {
		margin: 0.25em 0 0.5em;
		padding: 0;
	}

	dl dd {
		margin: 0 0 .5em 2em;
	}

	.head dd + dd { /* compact for header */
		margin-top: -.5em;
	}

	/* Style for algorithms */
	ol.algorithm ol:not(.algorithm),
	.algorithm > ol ol:not(.algorithm) {
	border-left: 0.5em solid #DEF;
	border-left: 0.5em solid var(--algo-border);
	}

	/* Put nice boxes around each algorithm. */
	[data-algorithm]:not(.heading) {
	 padding: .5em;
	 border: thin solid #ddd;
	 border: thin solid var(--algo-border);
	 border-radius: .5em;
	 margin: .5em calc(-0.5em - 1px);
	}
	[data-algorithm]:not(.heading) > :first-child {
	 margin-top: 0;
	}
	[data-algorithm]:not(.heading) > :last-child {
	 margin-bottom: 0;
	}

	/* Style for switch/case <dl>s */
	dl.switch > dd > ol.only,
	dl.switch > dd > .only > ol {
	margin-left: 0;
	}
	dl.switch > dd > ol.algorithm,
	dl.switch > dd > .algorithm > ol {
	margin-left: -2em;
	}
	dl.switch {
	padding-left: 2em;
	}
	dl.switch > dt {
	text-indent: -1.5em;
	margin-top: 1em;
	}
	dl.switch > dt + dt {
	margin-top: 0;
	}
	dl.switch > dt::before {
	content: '\21AA';
	padding: 0 0.5em 0 0;
	display: inline-block;
	width: 1em;
	text-align: right;
	line-height: 0.5em;
	}

/** Terminology Markup ********************************************************/


/******************************************************************************/
/*                                 Inline Markup                              */
/******************************************************************************/

/** Terminology Markup ********************************************************/
	dfn   { /* Defining instance */
		font-weight: bolder;
	}
	a > i { /* Instance of term */
		font-style: normal;
	}
	dt dfn code, code.idl {
		font-size: inherit;
	}
	dfn var {
		font-style: normal;
	}

/** Change Marking ************************************************************/

	del {
		color: #aa0000;
		color: var(--del-text);
		background: transparent;
		background: var(--del-bg);
		text-decoration: line-through;
	}
	ins {
		color: #006100;
		color: var(--ins-text);
		background: transparent;
		background: var(--ins-bg);
		text-decoration: underline;
	}

	/* for amendments (candidate/proposed changes) */

	.amendment ins, .correction ins, .addition ins,
	ins[class^=c] {
		text-decoration-style: dotted;
	}
	.amendment del, .correction del, .addition del,
	del[class^=c] {
		text-decoration-style: dotted;
	}
	.amendment.proposed ins, .correction.proposed ins, .addition.proposed ins,
	ins[class^=c].proposed {
		text-decoration-style: double;
	}
	.amendment.proposed del, .correction.proposed del, .addition.proposed del,
	del[class^=c].proposed {
		text-decoration-style: double;
	}

/** Miscellaneous improvements to inline formatting ***************************/

	sup {
		vertical-align: super;
		font-size: 80%
	}

/******************************************************************************/
/*                                    Code                                    */
/******************************************************************************/

/** General monospace/pre rules ***********************************************/

	pre, code, samp {
		font-family: Menlo, Consolas, "DejaVu Sans Mono", Monaco, monospace;
		font-size: .9em;
		hyphens: none;
		text-transform: none;
		text-align: left;
		text-align: start;
		font-variant: normal;
		orphans: 3;
		widows: 3;
		page-break-before: avoid;
	}
	pre code,
	code code {
		font-size: 100%;
	}

	pre {
		margin-top: 1em;
		margin-bottom: 1em;
		overflow: auto;
	}

/** Inline Code fragments *****************************************************/

	/* Do something nice. */

/******************************************************************************/
/*                                    Links                                   */
/******************************************************************************/

/** General Hyperlinks ********************************************************/

	/* We hyperlink a lot, so make it less intrusive */
	a[href] {
		color: #034575;
		color: var(--a-normal-text);
		text-decoration: underline #707070;
		text-decoration: underline var(--a-normal-underline);
		text-decoration-skip-ink: none;
	}
	a:visited {
		color: #034575;
		color: var(--a-visited-text);
		text-decoration-color: #bbb;
		text-decoration-color: var(--a-visited-underline);
	}

	/* Indicate interaction with the link */
	a[href]:focus,
	a[href]:hover {
		text-decoration-thickness: 2px;
	}
	a[href]:active {
		color: #c00;
		color: var(--a-active-text);
		text-decoration-color: #c00;
		text-decoration-color: var(--a-active-underline);
	}

	/* Backout above styling for W3C logo */
	.head .logo,
	.head .logo a {
		border: none;
		text-decoration: none;
		background: transparent;
	}

/******************************************************************************/
/*                                    Images                                  */
/******************************************************************************/

	img {
		border-style: none;
	}

	img, svg {
		/* Intentionally not color-scheme aware. */
		background: white;
	}

	/* For autogen numbers, add
	  .caption::before, figcaption::before { content: "Figure " counter(figure) ". "; }
	*/

	figure, .figure, .sidefigure {
		page-break-inside: avoid;
		text-align: center;
		margin: 2.5em 0;
	}
	.figure img,	.sidefigure img,	figure img,
	.figure object, .sidefigure object, figure object {
		max-width: 100%;
		margin: auto;
		height: auto;
	}
	.figure pre, .sidefigure pre, figure pre {
		text-align: left;
		display: table;
		margin: 1em auto;
	}
	.figure table, figure table {
		margin: auto;
	}
	@media screen and (min-width: 20em) {
		.sidefigure {
			float: right;
			width: 50%;
			margin: 0 0 0.5em 0.5em;
		}
	}
	.caption, figcaption, caption {
		font-style: italic;
		font-size: 90%;
	}
	.caption::before, figcaption::before, figcaption > .marker {
		font-weight: bold;
	}
	.caption, figcaption {
		counter-increment: figure;
	}

	/* DL list is indented 2em, but figure inside it is not */
	dd > .figure, dd > figure { margin-left: -2em; }

/******************************************************************************/
/*                             Colored Boxes                                  */
/******************************************************************************/

	.issue, .note, .example, .assertion, .advisement, blockquote,
	.amendment, .correction, .addition {
		margin: 1em auto;
		padding: .5em;
		border: .5em;
		border-left-style: solid;
		page-break-inside: avoid;
	}
	span.issue, span.note {
		padding: .1em .5em .15em;
		border-right-style: solid;
	}

	blockquote > :first-child,
	.note  > p:first-child,
	.issue > p:first-child,
	.amendment > p:first-child,
	.correction > p:first-child,
	.addition > p:first-child {
		margin-top: 0;
	}
	blockquote > :last-child,
	.note  > p:last-child,
	.issue > p:last-child,
	.amendment > p:last-child,
	.correction > p:last-child,
	.addition > p:last-child {
		margin-bottom: 0;
	}


	.issue::before, .issue > .marker,
	.example::before, .example > .marker,
	.note::before, .note > .marker,
	details.note > summary > .marker,
	.amendment::before, .amendment > .marker,
	details.amendment > summary > .marker,
	.addition::before, .addition > .marker,
	addition.amendment > summary > .marker,
	.correction::before, .correction > .marker,
	correction.amendment > summary > .marker
	{
		text-transform: uppercase;
		padding-right: 1em;
	}

	.example::before, .example > .marker {
		display: block;
		padding-right: 0em;
	}

/** Blockquotes ***************************************************************/

	blockquote {
		border-color: silver;
		border-color: var(--blockquote-border);
		background: transparent;
		background: var(--blockquote-bg);
		color: currentcolor;
		color: var(--blockquote-text);
	}

/** Open issue ****************************************************************/

	.issue {
		border-color: #e05252;
		border-color: var(--issue-border);
		background: #fbe9e9;
		background: var(--issue-bg);
		color: black;
		color: var(--issue-text);
		counter-increment: issue;
		overflow: auto;
	}
	.issue::before, .issue > .marker {
		color: #831616;
		color: var(--issueheading-text);
	}
	/* Add .issue::before { content: "Issue " counter(issue) " "; } for autogen numbers,
	  or use class="marker" to mark up the issue number in source. */

/** Example *******************************************************************/

	.example {
		border-color: #e0cb52;
		border-color: var(--example-border);
		background: #fcfaee;
		background: var(--example-bg);
		color: black;
		color: var(--example-text);
		counter-increment: example;
		overflow: auto;
		clear: both;
	}
	.example::before, .example > .marker {
		color: #574b0f;
		color: var(--exampleheading-text);
	}
	/* Add .example::before { content: "Example " counter(example) " "; } for autogen numbers,
	  or use class="marker" to mark up the example number in source. */

/** Non-normative Note ********************************************************/

	.note {
		border-color: #52e052;
		border-color: var(--note-border);
		background: #e9fbe9;
		background: var(--note-bg);
		color: black;
		color: var(--note-text);
		overflow: auto;
	}

	.note::before, .note > .marker,
	details.note > summary {
		color: hsl(120, 70%, 30%);
		color: var(--noteheading-text);
	}
	/* Add .note::before { content: "Note "; } for autogen label,
	  or use class="marker" to mark up the label in source. */

	details.note[open] > summary {
		border-bottom: 1px silver solid;
		border-bottom: 1px var(--notesummary-underline) solid;
	}

/** Assertion Box *************************************************************/
	/*  for assertions in algorithms */

	.assertion {
		border-color: #AAA;
		border-color: var(--assertion-border);
		background: #EEE;
		background: var(--assertion-bg);
		color: black;
		color: var(--assertion-text);
	}

/** Advisement Box ************************************************************/
	/*  for attention-grabbing normative statements */

	.advisement {
		border-color: orange;
		border-color: var(--advisement-border);
		border-style: none solid;
		background: #fec;
		background: var(--advisement-bg);
		color: black;
		color: var(--advisement-text);
	}
	strong.advisement {
		display: block;
		text-align: center;
	}
	.advisement::before, .advisement > .marker {
		color: #b35f00;
		color: var(--advisementheading-text);
	}

/** Amendment Box *************************************************************/

	.amendment, .correction, .addition {
		border-color: #330099;
		border-color: var(--amendment-border);
		background: #F5F0FF;
		background: var(--amendment-bg);
		color: black;
		color: var(--amendment-text);
	}
	.amendment.proposed, .correction.proposed, .addition.proposed {
		border-style: solid;
		border-block-width: 0.25em;
	}
	.amendment::before, .amendment > .marker,
	details.amendment > summary::before, details.amendment > summary > .marker,
	.correction::before, .correction > .marker,
	details.correction > summary::before, details.correction > summary > .marker,
	.addition::before, .addition > .marker,
	details.addition > summary::before, details.addition > summary > .marker {
		color: #220066;
		color: var(--amendmentheading-text);
	}
	.amendment.proposed::before, .amendment.proposed > .marker,
	details.amendment.proposed > summary::before, details.amendment.proposed > summary > .marker,
	.correction.proposed::before, .correction.proposed > .marker,
	details.correction.proposed > summary::before, details.correction.proposed > summary > .marker,
	.addition.proposed::before, .addition.proposed > .marker,
	details.addition.proposed > summary::before, details.addition.proposed > summary > .marker {
		font-weight: bold;
	}

/** Spec Obsoletion Notice ****************************************************/
	/* obnoxious obsoletion notice for older/abandoned specs. */

	details {
		display: block;
	}
	summary {
		font-weight: bolder;
	}

	.annoying-warning:not(details),
	details.annoying-warning:not([open]) > summary,
	details.annoying-warning[open] {
		background: hsla(40,100%,50%,0.95);
		background: var(--warning-bg);
		color: black;
		color: var(--warning-text);
		padding: .75em 1em;
		border: red;
		border: var(--warning-border);
		border-style: solid none;
		box-shadow: 0 2px 8px black;
		text-align: center;
	}
	.annoying-warning :last-child {
		margin-bottom: 0;
	}

@media not print {
	details.annoying-warning[open] {
		position: fixed;
		left: 0;
		right: 0;
		bottom: 2em;
		z-index: 1000;
	}
}

	details.annoying-warning:not([open]) > summary {
		text-align: center;
	}

/** Entity Definition Boxes ***************************************************/

	.def {
		padding: .5em 1em;
		background: #def;
		background: var(--def-bg);
		margin: 1.2em 0;
		border-left: 0.5em solid #8ccbf2;
		border-left: 0.5em solid var(--def-border);
		color: black;
		color: var(--def-text);
	}

/******************************************************************************/
/*                                    Tables                                  */
/******************************************************************************/

	th, td {
		text-align: left;
		text-align: start;
	}

/** Property/Descriptor Definition Tables *************************************/

	table.def {
		/* inherits .def box styling, see above */
		width: 100%;
		border-spacing: 0;
	}

	table.def td,
	table.def th {
		padding: 0.5em;
		vertical-align: baseline;
		border-bottom: 1px solid #bbd7e9;
		border-bottom: 1px solid var(--defrow-border);
	}

	table.def > tbody > tr:last-child th,
	table.def > tbody > tr:last-child td {
		border-bottom: 0;
	}

	table.def th {
		font-style: italic;
		font-weight: normal;
		padding-left: 1em;
		width: 3em;
	}

	/* For when values are extra-complex and need formatting for readability */
	table td.pre {
		white-space: pre-wrap;
	}

	/* A footnote at the bottom of a def table */
	table.def td.footnote {
		padding-top: 0.6em;
	}
	table.def td.footnote::before {
		content: " ";
		display: block;
		height: 0.6em;
		width: 4em;
		border-top: thin solid;
	}

/** Data tables (and properly marked-up index tables) *************************/
	/*
		<table class="data"> highlights structural relationships in a table
		when correct markup is used (e.g. thead/tbody, th vs. td, scope attribute)

		Use class="complex data" for particularly complicated tables --
		(This will draw more lines: busier, but clearer.)

		Use class="long" on table cells with paragraph-like contents
		(This will adjust text alignment accordingly.)
		Alternately use class="longlastcol" on tables, to have the last column assume "long".
	*/

	table {
		word-wrap: normal;
		overflow-wrap: normal;
		hyphens: manual;
	}

	table.data,
	table.index {
		margin: 1em auto;
		border-collapse: collapse;
		border: hidden;
		width: 100%;
	}
	table.data caption,
	table.index caption {
		max-width: 50em;
		margin: 0 auto 1em;
	}

	table.data td,  table.data th,
	table.index td, table.index th {
		padding: 0.5em 1em;
		border-width: 1px;
		border-color: silver;
		border-color: var(--datacell-border);
		border-top-style: solid;
	}

	table.data thead td:empty {
		padding: 0;
		border: 0;
	}

	table.data  thead,
	table.index thead,
	table.data  tbody,
	table.index tbody {
		border-bottom: 2px solid;
	}

	table.data colgroup,
	table.index colgroup {
		border-left: 2px solid;
	}

	table.data  tbody th:first-child,
	table.index tbody th:first-child  {
		border-right: 2px solid;
		border-top: 1px solid silver;
		border-top: 1px solid var(--datacell-border);
		padding-right: 1em;
	}

	table.data th[colspan],
	table.data td[colspan] {
		text-align: center;
	}

	table.complex.data th,
	table.complex.data td {
		border: 1px solid silver;
		border: 1px solid var(--datacell-border);
		text-align: center;
	}

	table.data.longlastcol td:last-child,
	table.data td.long {
		vertical-align: baseline;
		text-align: left;
	}

	table.data img {
		vertical-align: middle;
	}


/*
Alternate table alignment rules

	table.data,
	table.index {
		text-align: center;
	}

	table.data  thead th[scope="row"],
	table.index thead th[scope="row"] {
		text-align: right;
	}

	table.data  tbody th:first-child,
	table.index tbody th:first-child  {
		text-align: right;
	}

Possible extra rowspan handling

	table.data  tbody th[rowspan]:not([rowspan='1']),
	table.index tbody th[rowspan]:not([rowspan='1']),
	table.data  tbody td[rowspan]:not([rowspan='1']),
	table.index tbody td[rowspan]:not([rowspan='1']) {
		border-left: 1px solid silver;
	}

	table.data  tbody th[rowspan]:first-child,
	table.index tbody th[rowspan]:first-child,
	table.data  tbody td[rowspan]:first-child,
	table.index tbody td[rowspan]:first-child{
		border-left: 0;
		border-right: 1px solid silver;
	}
*/

/******************************************************************************/
/*                                  Indices                                   */
/******************************************************************************/


/** Table of Contents *********************************************************/

	.toc a {
		/* More spacing; use padding to make it part of the click target. */
		padding: 0.1rem 1px 0;
		/* Larger, more consistently-sized click target */
		display: block;
		/* Switch to using border-bottom for underlines */
		text-decoration: none;
		border-bottom: 1px solid;
		/* Reverse color scheme */
		color: black;
		color: var(--toclink-text);
		border-color: #3980b5;
		border-color: var(--toclink-underline);
	}
	.toc a:visited {
		color: black;
		color: var(--toclink-visited-text);
		border-color: #054572;
		border-color: var(--toclink-visited-underline);
	}
	.toc a:focus,
	.toc a:hover {
		background: rgba(75%, 75%, 75%, .25);
		background: var(--a-hover-bg);
		border-bottom-width: 3px;
		margin-bottom: -2px;
	}
	.toc a:not(:focus):not(:hover) {
		/* Allow colors to cascade through from link styling */
		border-bottom-color: transparent;
	}

	.toc, .toc ol, .toc ul, .toc li {
		list-style: none; /* Numbers must be inlined into source */
		/* because generated content isn't search/selectable and markers can't do multilevel yet */
		margin:  0;
		padding: 0;
	}
	.toc {
		line-height: 1.1em;
	}

	/* ToC not indented until third level, but font style & margins show hierarchy */
	.toc > li			{ font-weight: bold;   }
	.toc > li li		 { font-weight: normal; }
	.toc > li li li	  { font-size:   95%;	}
	.toc > li li li li	{ font-size:   90%;	}
	.toc > li li li li li { font-size:   85%;	}

	/* @supports not (display:grid) { */
		.toc > li			{ margin: 1.5rem 0;	}
		.toc > li li		 { margin: 0.3rem 0;	}
		.toc > li li li	  { margin-left: 2rem;   }

		/* Section numbers in a column of their own */
		.toc .secno {
			float: left;
			width: 4rem;
			white-space: nowrap;
		}
		.toc > li li li li .secno { font-size: 85%; }
		.toc > li li li li li .secno { font-size: 100%; }

		.toc li {
			clear: both;
		}

		:not(li) > .toc			 { margin-left:  5rem; }
		.toc .secno				 { margin-left: -5rem; }
		.toc > li li li .secno	  { margin-left: -7rem; }
		.toc > li li li li .secno	{ margin-left: -9rem; }
		.toc > li li li li li .secno { margin-left: -11rem; }

		/* Tighten up indentation in narrow ToCs */
		@media (max-width: 30em) {
			:not(li) > .toc			 { margin-left:  4rem; }
			.toc .secno				 { margin-left: -4rem; }
			.toc > li li li			 { margin-left:  1rem; }
			.toc > li li li .secno	  { margin-left: -5rem; }
			.toc > li li li li .secno	{ margin-left: -6rem; }
			.toc > li li li li li .secno { margin-left: -7rem; }
		}
		/* Loosen it on wide screens */
		@media screen and (min-width: 78em) {
			body:not(.toc-inline) :not(li) > .toc			 { margin-left:  4rem; }
			body:not(.toc-inline) .toc .secno				 { margin-left: -4rem; }
			body:not(.toc-inline) .toc > li li li			 { margin-left:  1rem; }
			body:not(.toc-inline) .toc > li li li .secno	  { margin-left: -5rem; }
			body:not(.toc-inline) .toc > li li li li .secno	{ margin-left: -6rem; }
			body:not(.toc-inline) .toc > li li li li li .secno { margin-left: -7rem; }
	}
	/* } */

	@supports (display:grid) and (display:contents) {
		/* Use #toc over .toc to override non-@supports rules. */
		#toc {
			display: grid;
			align-content: start;
			grid-template-columns: auto 1fr;
			grid-column-gap: 1rem;
			column-gap: 1rem;
			grid-row-gap: .6rem;
			row-gap: .6rem;
		}
		#toc h2 {
			grid-column: 1 / -1;
			margin-bottom: 0;
		}
		#toc ol,
		#toc li,
		#toc a {
			display: contents;
			/* Switch <a> to subgrid when supported */
		}
		#toc span {
			margin: 0;
		}
		#toc > .toc > li > a > span {
			/* The spans of the top-level list,
			  comprising the first items of each top-level section. */
			margin-top: 1.1rem;
		}
		#toc#toc .secno { /* Ugh, need more specificity to override base.css */
			grid-column: 1;
			width: auto;
			margin-left: 0;
		}
		#toc .content {
			grid-column: 2;
			width: auto;
			margin-right: 1rem;
			border-bottom: 3px solid transparent;
			margin-bottom: -3px;
		}
		#toc .content:hover,
		#toc .content:focus {
			background: rgba(75%, 75%, 75%, .25);
			background: var(--a-hover-bg);
			border-bottom-color: #054572;
			border-bottom-color: var(--toclink-underline);
		}
		#toc li li li .content {
			margin-left: 1rem;
		}
		#toc li li li li .content {
			margin-left: 2rem;
		}
	}


/** Index *********************************************************************/

	/* Index Lists: Layout */
	ul.index	  { margin-left: 0; columns: 15em; text-indent: 1em hanging; }
	ul.index li	{ margin-left: 0; list-style: none; break-inside: avoid; }
	ul.index li li { margin-left: 1em; }
	ul.index dl	{ margin-top: 0; }
	ul.index dt	{ margin: .2em 0 .2em 20px;}
	ul.index dd	{ margin: .2em 0 .2em 40px;}
	/* Index Lists: Typography */
	ul.index ul,
	ul.index dl { font-size: smaller; }
	@media not print {
		ul.index li a + span {
			white-space: nowrap;
			color: transparent; }
		ul.index li a:hover + span,
		ul.index li a:focus + span {
			color: #707070;
			color: var(--indexinfo-text);
		}
	}

/** Index Tables *****************************************************/
	/* See also the data table styling section, which this effectively subclasses */

	table.index {
		font-size: small;
		border-collapse: collapse;
		border-spacing: 0;
		text-align: left;
		margin: 1em 0;
	}

	table.index td,
	table.index th {
		padding: 0.4em;
	}

	table.index tr:hover td:not([rowspan]),
	table.index tr:hover th:not([rowspan]) {
		color: black;
		color: var(--indextable-hover-text);
		background: #f7f8f9;
		background: var(--indextable-hover-bg);
	}

	/* The link in the first column in the property table (formerly a TD) */
	table.index th:first-child a {
		font-weight: bold;
	}

/** Outdated warning **********************************************************/

.outdated-spec {
	color: black;
	color: var(--outdatedspec-text);
	background-color: rgba(0,0,0,0.5);
	background-color: var(--outdatedspec-bg);
}

.outdated-warning {
	position: fixed;
	bottom: 50%;
	left: 0;
	right: 0;
	margin: 0 auto;
	width: 50%;
	background: maroon;
	background: var(--outdated-bg);
	color: white;
	color: var(--outdated-text);
	border-radius: 1em;
	box-shadow: 0 0 1em red;
	box-shadow: 0 0 1em var(--outdated-shadow);
	padding: 2em;
	text-align: center;
	z-index: 2;
}

.outdated-warning a {
	color: currentcolor;
	background: transparent;
}

.edited-rec-warning {
	background: darkorange;
	background: var(--editedrec-bg);
	box-shadow: 0 0 1em;
}

.outdated-warning button {
	color: var(--outdated-text);
	border-radius: 1em;
	box-shadow: 0 0 1em red;
	box-shadow: 0 0 1em var(--outdated-shadow);
	padding: 2em;
	text-align: center;
	z-index: 2;
}

.outdated-warning a {
	color: currentcolor;
	background: transparent;
}

.edited-rec-warning {
	background: darkorange;
	background: var(--editedrec-bg);
	box-shadow: 0 0 1em;
}

.outdated-warning button {
	position: absolute;
	top: 0;
	right:0;
	margin: 0;
	border: 0;
	padding: 0.25em 0.5em;
	background: transparent;
	color: white;
	color: var(--outdated-text);
	font:1em sans-serif;
	text-align:center;
}

.outdated-warning span {
	display: block;
}

.outdated-collapsed {
	bottom: 0;
	border-radius: 0;
	width: 100%;
	padding: 0;
}

/******************************************************************************/
/*                                    Print                                   */
/******************************************************************************/

	@media print {
		/* Pages have their own margins. */
		html {
			margin: 0;
		}
		/* Serif for print. */
		body {
			font-family: serif;
		}

		.outdated-warning {
			position: absolute;
			border-style: solid;
			border-color: red;
		}

		.outdated-warning input {
			display: none;
		}
	}
	@page {
		margin: 1.5cm 1.1cm;
	}



/******************************************************************************/
/*                             Overflow Control                               */
/******************************************************************************/

	.figure .caption, .sidefigure .caption, figcaption {
		/* in case figure is overlarge, limit caption to 50em */
		max-width: 50rem;
		margin-left: auto;
		margin-right: auto;
	}
	.overlarge {
		/* Magic to create good item positioning:
		  "content column" is 50ems wide at max; less on smaller screens.
		  Extra space (after ToC + content) is empty on the right.

		  1. When item < content column, centers item in column.
		  2. When content < item < available, left-aligns.
		  3. When item > available, fills available + scroll bar.
		*/
		display: grid;
		grid-template-columns: minmax(0, 50em);
	}
	.overlarge > table {
		/* limit preferred width of table */
		max-width: 50em;
		margin-left: auto;
		margin-right: auto;
	}

	@media (min-width: 55em) {
		.overlarge {
			margin-right: calc(13px + 26.5rem - 50vw);
			max-width: none;
		}
	}
	@media screen and (min-width: 78em) {
		body:not(.toc-inline) .overlarge {
			/* 30.5em body padding 50em content area */
			margin-right: calc(40em - 50vw) !important;
		}
	}
	@media screen and (min-width: 90em) {
		body:not(.toc-inline) .overlarge {
			/* 4em html margin 30.5em body padding 50em content area */
			margin-right: calc(84.5em - 100vw) !important;
		}
	}

	@media not print {
		.overlarge {
			overflow-x: auto;
			/* See Lea Verou's explanation background-attachment:
			* http://lea.verou.me/2012/04/background-attachment-local/
			*
			background: top left  / 4em 100% linear-gradient(to right,  #ffffff, rgba(255, 255, 255, 0)) local,
						top right / 4em 100% linear-gradient(to left, #ffffff, rgba(255, 255, 255, 0)) local,
						top left  / 1em 100% linear-gradient(to right,  #c3c3c5, rgba(195, 195, 197, 0)) scroll,
						top right / 1em 100% linear-gradient(to left, #c3c3c5, rgba(195, 195, 197, 0)) scroll,
						white;
			background-repeat: no-repeat;
			*/
		}
	}
</style>
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    table, th, td {
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    th, td {
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      padding: 0px 10px;
    }
    th {
      text-align: center;
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    del { background: #fcc; color: #000; text-decoration: line-through; }
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    blockquote c-[sd] { color: inherit; } /* Literal.String.Doc */
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    blockquote c-[sh] { color: inherit; } /* Literal.String.Heredoc */
    blockquote c-[si] { color: inherit; } /* Literal.String.Interpol */
    blockquote c-[sx] { color: inherit; } /* Literal.String.Other */
    blockquote c-[sr] { color: inherit; } /* Literal.String.Regex */
    blockquote c-[ss] { color: inherit; } /* Literal.String.Symbol */
    blockquote c-[vc] { color: inherit; } /* Name.Variable.Class */
    blockquote c-[vg] { color: inherit; } /* Name.Variable.Global */
    blockquote c-[vi] { color: inherit; } /* Name.Variable.Instance */
    blockquote c-[il] { color: inherit; } /* Literal.Number.Integer.Long */
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:root {
	/* Default (light) theme */
	--del-text-color: rgb(255, 25, 25);
	--del-text-decoration-color: rgba(180, 6, 6, 0.5);
	--del-text-background-color: rgba(255, 175, 175, 0.5);
	--ins-text-color: rgb(10, 180, 35);
	--ins-text-decoration-color: rgba(10, 180, 35, 0.5);
	--ins-text-background-color: rgba(175, 250, 190, 0.5);
	--diff-ins-text-color: rgb(0, 238, 255);
	--diff-ins-text-decoration-color: rgba(99, 0, 129, 0.5);
	--diff-ins-text-background-color: rgba(175, 222, 250, 0.5);
	--diff-del-text-color: rgb(225, 148, 255);
	--diff-del-text-decoration-color: rgba(99, 0, 129, 0.5);
	--diff-del-text-background-color: rgba(244, 175, 250, 0.5);
}

/* dark theme */
@media (prefers-color-scheme: dark) {
	:root {
		--del-text-color: rgb(255, 52, 52);
		--del-text-decoration-color: rgba(82, 25, 25, 0.5);
		--del-text-background-color: rgba(82, 25, 25, 0.5);
		--ins-text-color: rgb(140, 255, 140);
		--ins-text-decoration-color: rgba(140, 255, 140, 0.5);
		--ins-text-background-color: rgba(25, 82, 25, 0.5);
		--diff-ins-text-color: rgb(91, 250, 255);
		--diff-ins-text-decoration-color: rgba(91, 250, 255, 0.5);
		--diff-ins-text-background-color: rgba(0, 56, 94, 0.5);
		--diff-del-text-color: rgb(244, 175, 250);
		--diff-del-text-decoration-color: rgba(244, 175, 250, 0.5);
		--diff-del-text-background-color: rgba(152, 0, 199, 0.5);
	}
}

@media print {
	.pagebreak { break-after: always }
}

.tg  {
	border-collapse: collapse;
	border-spacing:0;
}

.tg td{
	padding:10px 10px;
	border-style: solid;
	border-width:1px;
	overflow: hidden;
	word-break: normal;
	border-color: var(--table-border-color, inherit);
}
.tg th{
	font-weight: normal;
	padding: 10px 10px;
	border-style: solid;
	border-width: 1px;
	overflow: hidden;
	word-break: normal;
	border-color: black;
}
.tg .tg-c3ow { 
	border-color: inherit;
	text-align: center;
	vertical-align: top
}

.ins, ins, ins p, ins div, span.ins, span.ins * {
	background-color: var(--ins-text-background-color);
	background: var(--ins-text-background-color);
	color: var(--ins-text-color);
	text-decoration: underline;
	text-decoration-color: var(--ins-text-decoration-color);
}

.diff-ins, diff-ins, diff-ins p, diff-ins div, span.diff-ins, span.diff-ins * {
	background-color: var(--diff-ins-text-background-color);
	background: var(--diff-ins-text-background-color);
	color: var(--diff-ins-text-color);
	text-decoration: underline double;
	text-decoration-color: var(--diff-ins-text-decoration-color);
}

.del, del, del p, del div, span.del, span.del * {
	background-color: var(--del-text-background-color);
	background: var(--del-text-background-color);
	color: var(--del-text-color);
	text-decoration: line-through;
	text-decoration-color: var(--del-text-decoration-color);
}

.diff-del, diff-del, diff-del p, diff-del div, span.diff-del, span.diff-del * {
	background-color: var(--diff-del-text-background-color);
	background: var(--diff-del-text-background-color);
	color: var(--diff-del-text-color);
	text-decoration: line-through double;
	text-decoration-color: var(--diff-del-text-decoration-color);
}

code.c-kw {
	font-weight: bold;
}

math, span.math {
	font-family: serif;
	font-style: italic;
}

ul {
	list-style-type: "— ";
}

.wording-clause {
	counter-reset: wording-paragraph;
}

.wording-clause-header {
	font-size: 115%;
	display: block;
	padding-bottom: 1em;
	clear: both;
}

.wording-clause-number {
	font-weight: bold;
}

.wording-clause-title {
	font-weight: bold;
	margin: 2em;
}

.wording-clause-stable-tag {
	float: right;
}

.wording-clause-section-title {
	font-size: 105%;
	font-weight: bold;
}

.clause-stable-tag {
	float: right;
}

.footnote-ref {
	font-size: 75%;
	vertical-align: super;
}

.footnote {
	font-size: 75%;
	vertical-align: bottom;
}

div.wording-section {
	counter-reset: wording-paragraph;
}

div.wording-numbered, div.wording-newnumbered {
	margin-left: 2.5em;
	margin-top: 1em;
	margin-bottom: 1em;
}

div.wording-numbered:before, div.wording-newnumbered:before {
	position: absolute;
	margin-left: -2.5em;
	display: block;
}

div.wording-numbered:before {
	content: counter(wording-paragraph);
	counter-increment: wording-paragraph;
	font-size: smaller;
}

div.wording-newnumbered:before {
	content: counter(wording-paragraph)"✨";
	counter-increment: wording-paragraph;
	font-size: smaller;
}

div.wording-numbered-list ul, div.wording-newnumbered ul {
	counter-reset: wording-list-item;
}

div.wording-numbered-list li, div.wording-newnumbered li {
	margin-left: 4em;
}

div.wording-numbered-list li:before, div.wording-newnumbered li:before {
	position: absolute;
	margin-left: -4em;
	display: block;
}

div.wording-numbered-list li:before {
	font-size: smaller;
	content: "(" counter(wording-paragraph) "." counter(wording-list-item) ")";
	counter-increment: wording-list-item;
}

div.wording-newnumbered-list li:before {
	content: "(✨" counter(wording-paragraph) "." counter(wording-list-item) ")";
	counter-increment: wording-list-item;
}

div.wording-numbered-0 {
	counter-reset: wording-paragraph -1;
}

div.wording-numbered-1 {
	counter-reset: wording-paragraph 0;
}

div.wording-numbered-2 {
	counter-reset: wording-paragraph 1;
}

div.wording-numbered-3 {
	counter-reset: wording-paragraph 2;
}

div.wording-numbered-4 {
	counter-reset: wording-paragraph 3;
}

div.wording-numbered-5 {
	counter-reset: wording-paragraph 4;
}

div.wording-numbered-6 {
	counter-reset: wording-paragraph 5;
}

div.wording-numbered-7 {
	counter-reset: wording-paragraph 6;
}

div.wording-numbered-8 {
	counter-reset: wording-paragraph 7;
}

div.wording-numbered-9 {
	counter-reset: wording-paragraph 8;
}

div.wording-numbered-10 {
	counter-reset: wording-paragraph 9;
}

div.wording-numbered-11 {
	counter-reset: wording-paragraph 10;
}

div.wording-numbered-12 {
	counter-reset: wording-paragraph 11;
}

div.wording-numbered-13 {
	counter-reset: wording-paragraph 12;
}

div.wording-numbered-14 {
	counter-reset: wording-paragraph 13;
}

div.wording-numbered-15 {
	counter-reset: wording-paragraph 14;
}

div.wording-numbered-16 {
	counter-reset: wording-paragraph 15;
}

div.wording-numbered-17 {
	counter-reset: wording-paragraph 16;
}

div.wording-numbered-18 {
	counter-reset: wording-paragraph 17;
}

div.wording-numbered-19 {
	counter-reset: wording-paragraph 18;
}

div.wording-numbered-20 {
	counter-reset: wording-paragraph 19;
}
</style>
<style>
@media (prefers-color-scheme: dark) {
	:root {
		--bg-color: rgba(0, 0, 0, 0);
	}

	ins { background: rgba(0, 20, 0); color: rgba(115, 255, 110); }
	del { background: rgba(20, 0, 0); color: rgb(255, 124, 124); text-decoration: line-through; }
	recent-ins { background: rgba(0, 20, 0); color: rgba(80, 80, 255); }
	recent-del { background: rgba(20, 0, 0); color: rgb(255, 156, 56); text-decoration: line-through; }
	blockquote .highlight:not(.idl) { padding: 0.5em }
	blockquote ins .highlight:not(.idl) { background: rgba( 0, 20, 0); }
	blockquote del .highlight:not(.idl) { background: rgba(20,  0, 0); }
	blockquote code.highlight:not(.idl) { background: inherit; padding: initial; }

	c-[a] { color: #e783b4 } /* Keyword.Declaration */
	c-[b] { color: #e783b4 } /* Keyword.Type */
	c-[c] { color: #6ad4cc } /* Comment */
	c-[d] { color: #6ad4cc } /* Comment.Multiline */
	c-[e] { color: #92cbf5 } /* Name.Attribute */
	c-[f] { color: #b58900 } /* Name.Tag */
	c-[g] { color: #cb4b16 } /* Name.Variable */
	c-[k] { color: #e783b4 } /* Keyword */
	c-[l] { color: #a2b1b6 } /* Literal */
	c-[m] { color: #a2b1b6 } /* Literal.Number */
	c-[n] { color: #92cbf5 } /* Name */
	c-[o] { color: #a2b1b6 } /* Operator */
	c-[p] { color: #a2b1b6 } /* Punctuation */
	c-[s] { color: #a0a3e5 } /* Literal.String */
	c-[t] { color: #a0a3e5 } /* Literal.String.Single */
	c-[u] { color: #a0a3e5 } /* Literal.String.Double */
	c-[ch] { color: #6ad4cc } /* Comment.Hashbang */
	c-[cp] { color: #6ad4cc } /* Comment.Preproc */
	c-[cpf] { color: #6ad4cc } /* Comment.PreprocFile */
	c-[c1] { color: #6ad4cc } /* Comment.Single */
	c-[cs] { color: #6ad4cc } /* Comment.Special */
	c-[kc] { color: #e783b4 } /* Keyword.Constant */
	c-[kn] { color: #e783b4 } /* Keyword.Namespace */
	c-[kp] { color: #e783b4 } /* Keyword.Pseudo */
	c-[kr] { color: #e783b4 } /* Keyword.Reserved */
	c-[ld] { color: #a2b1b6 } /* Literal.Date */
	c-[nc] { color: #92cbf5 } /* Name.Class */
	c-[no] { color: #92cbf5 } /* Name.Constant */
	c-[nd] { color: #92cbf5 } /* Name.Decorator */
	c-[ni] { color: #92cbf5 } /* Name.Entity */
	c-[ne] { color: #92cbf5 } /* Name.Exception */
	c-[nf] { color: #92cbf5 } /* Name.Function */
	c-[nl] { color: #92cbf5 } /* Name.Label */
	c-[nn] { color: #92cbf5 } /* Name.Namespace */
	c-[py] { color: #92cbf5 } /* Name.Property */
	c-[ow] { color: #a2b1b6 } /* Operator.Word */
	c-[mb] { color: #a2b1b6 } /* Literal.Number.Bin */
	c-[mf] { color: #a2b1b6 } /* Literal.Number.Float */
	c-[mh] { color: #a2b1b6 } /* Literal.Number.Hex */
	c-[mi] { color: #a2b1b6 } /* Literal.Number.Integer */
	c-[mo] { color: #a2b1b6 } /* Literal.Number.Oct */
	c-[sa] { color: #a0a3e5 } /* Literal.String.Affix */
	c-[sb] { color: #a0a3e5 } /* Literal.String.Backtick */
	c-[sc] { color: #a0a3e5 } /* Literal.String.Char */
	c-[dl] { color: #a0a3e5 } /* Literal.String.Delimiter */
	c-[sd] { color: #a0a3e5 } /* Literal.String.Doc */
	c-[se] { color: #a0a3e5 } /* Literal.String.Escape */
	c-[sh] { color: #a0a3e5 } /* Literal.String.Heredoc */
	c-[si] { color: #a0a3e5 } /* Literal.String.Interpol */
	c-[sx] { color: #a0a3e5 } /* Literal.String.Other */
	c-[sr] { color: #a0a3e5 } /* Literal.String.Regex */
	c-[ss] { color: #a0a3e5 } /* Literal.String.Symbol */
	c-[fm] { color: #92cbf5 } /* Name.Function.Magic */
	c-[vc] { color: #cb4b16 } /* Name.Variable.Class */
	c-[vg] { color: #cb4b16 } /* Name.Variable.Global */
	c-[vi] { color: #cb4b16 } /* Name.Variable.Instance */
	c-[vm] { color: #cb4b16 } /* Name.Variable.Magic */
	c-[il] { color: #a2b1b6 } /* Literal.Number.Integer.Long */

	blockquote c-[b] { color: #e783b4 } /* Keyword.Type */
	blockquote c-[a] { color: #e783b4 } /* Keyword.Declaration */
	blockquote c-[c] { color: #6ad4cc } /* Comment */
	blockquote c-[d] { color: #6ad4cc } /* Comment.Multiline */
	blockquote c-[e] { color: #92cbf5 } /* Name.Attribute */
	blockquote c-[f] { color: #b58900 } /* Name.Tag */
	blockquote c-[g] { color: #cb4b16 } /* Name.Variable */
	blockquote c-[k] { color: #e783b4 } /* Keyword */
	blockquote c-[l] { color: #a2b1b6 } /* Literal */
	blockquote c-[m] { color: #a2b1b6 } /* Literal.Number */
	blockquote c-[n] { color: #92cbf5 } /* Name */
	blockquote c-[o] { color: #a2b1b6 } /* Operator */
	blockquote c-[p] { color: #a2b1b6 } /* Punctuation */
	blockquote c-[s] { color: #a0a3e5 } /* Literal.String */
	blockquote c-[t] { color: #a0a3e5 } /* Literal.String.Single */
	blockquote c-[u] { color: #a0a3e5 } /* Literal.String.Double */
	blockquote c-[ch] { color: #6ad4cc } /* Comment.Hashbang */
	blockquote c-[cp] { color: #6ad4cc } /* Comment.Preproc */
	blockquote c-[cpf] { color: #6ad4cc } /* Comment.PreprocFile */
	blockquote c-[c1] { color: #6ad4cc } /* Comment.Single */
	blockquote c-[cs] { color: #6ad4cc } /* Comment.Special */
	blockquote c-[kc] { color: #e783b4 } /* Keyword.Constant */
	blockquote c-[kn] { color: #e783b4 } /* Keyword.Namespace */
	blockquote c-[kp] { color: #e783b4 } /* Keyword.Pseudo */
	blockquote c-[kr] { color: #e783b4 } /* Keyword.Reserved */
	blockquote c-[ld] { color: #a2b1b6 } /* Literal.Date */
	blockquote c-[nc] { color: #92cbf5 } /* Name.Class */
	blockquote c-[no] { color: #92cbf5 } /* Name.Constant */
	blockquote c-[nd] { color: #92cbf5 } /* Name.Decorator */
	blockquote c-[ni] { color: #92cbf5 } /* Name.Entity */
	blockquote c-[ne] { color: #92cbf5 } /* Name.Exception */
	blockquote c-[nf] { color: #92cbf5 } /* Name.Function */
	blockquote c-[nl] { color: #92cbf5 } /* Name.Label */
	blockquote c-[nn] { color: #92cbf5 } /* Name.Namespace */
	blockquote c-[py] { color: #92cbf5 } /* Name.Property */
	blockquote c-[ow] { color: #a2b1b6 } /* Operator.Word */
	blockquote c-[mb] { color: #a2b1b6 } /* Literal.Number.Bin */
	blockquote c-[mf] { color: #a2b1b6 } /* Literal.Number.Float */
	blockquote c-[mh] { color: #a2b1b6 } /* Literal.Number.Hex */
	blockquote c-[mi] { color: #a2b1b6 } /* Literal.Number.Integer */
	blockquote c-[mo] { color: #a2b1b6 } /* Literal.Number.Oct */
	blockquote c-[sa] { color: #a0a3e5 } /* Literal.String.Affix */
	blockquote c-[sb] { color: #a0a3e5 } /* Literal.String.Backtick */
	blockquote c-[sc] { color: #a0a3e5 } /* Literal.String.Char */
	blockquote c-[dl] { color: #a0a3e5 } /* Literal.String.Delimiter */
	blockquote c-[sd] { color: #a0a3e5 } /* Literal.String.Doc */
	blockquote c-[se] { color: #a0a3e5 } /* Literal.String.Escape */
	blockquote c-[sh] { color: #a0a3e5 } /* Literal.String.Heredoc */
	blockquote c-[si] { color: #a0a3e5 } /* Literal.String.Interpol */
	blockquote c-[sx] { color: #a0a3e5 } /* Literal.String.Other */
	blockquote c-[sr] { color: #a0a3e5 } /* Literal.String.Regex */
	blockquote c-[ss] { color: #a0a3e5 } /* Literal.String.Symbol */
	blockquote c-[fm] { color: #92cbf5 } /* Name.Function.Magic */
	blockquote c-[vc] { color: #cb4b16 } /* Name.Variable.Class */
	blockquote c-[vg] { color: #cb4b16 } /* Name.Variable.Global */
	blockquote c-[vi] { color: #cb4b16 } /* Name.Variable.Instance */
	blockquote c-[vm] { color: #cb4b16 } /* Name.Variable.Magic */
	blockquote c-[il] { color: #a2b1b6 } /* Literal.Number.Integer.Long */
}

@media (prefers-color-scheme: light) {
	:root {
		--bg-color: rgba(255, 255, 255, 0);
	}
	ins { background: rgba(200, 255, 200); color: rgba(0, 20, 0); }
	del { background: rgba(255, 200, 200); color: rgb(20, 0, 0); text-decoration: line-through; }
	blockquote .highlight:not(.idl) { padding: 0.5em }
	blockquote ins .highlight:not(.idl) { background: rgba(200, 255, 200); }
	blockquote del .highlight:not(.idl) { background: rgba(255, 200, 200); }
	blockquote code.highlight:not(.idl) { background: inherit; padding: initial; }
}
</style>
<style>/* Boilerplate: style-autolinks */
.css.css, .property.property, .descriptor.descriptor {
    color: var(--a-normal-text);
    font-size: inherit;
    font-family: inherit;
}
.css::before, .property::before, .descriptor::before {
    content: "‘";
}
.css::after, .property::after, .descriptor::after {
    content: "’";
}
.property, .descriptor {
    /* Don't wrap property and descriptor names */
    white-space: nowrap;
}
.type { /* CSS value <type> */
    font-style: italic;
}
pre .property::before, pre .property::after {
    content: "";
}
[data-link-type="property"]::before,
[data-link-type="propdesc"]::before,
[data-link-type="descriptor"]::before,
[data-link-type="value"]::before,
[data-link-type="function"]::before,
[data-link-type="at-rule"]::before,
[data-link-type="selector"]::before,
[data-link-type="maybe"]::before {
    content: "‘";
}
[data-link-type="property"]::after,
[data-link-type="propdesc"]::after,
[data-link-type="descriptor"]::after,
[data-link-type="value"]::after,
[data-link-type="function"]::after,
[data-link-type="at-rule"]::after,
[data-link-type="selector"]::after,
[data-link-type="maybe"]::after {
    content: "’";
}

[data-link-type].production::before,
[data-link-type].production::after,
.prod [data-link-type]::before,
.prod [data-link-type]::after {
    content: "";
}

[data-link-type=element],
[data-link-type=element-attr] {
    font-family: Menlo, Consolas, "DejaVu Sans Mono", monospace;
    font-size: .9em;
}
[data-link-type=element]::before { content: "<" }
[data-link-type=element]::after  { content: ">" }

[data-link-type=biblio] {
    white-space: pre;
}

@media (prefers-color-scheme: dark) {
    :root {
        --selflink-text: black;
        --selflink-bg: silver;
        --selflink-hover-text: white;
    }
}
</style>
<style>/* Boilerplate: style-colors */

/* Any --*-text not paired with a --*-bg is assumed to have a transparent bg */
:root {
    color-scheme: light dark;

    --text: black;
    --bg: white;

    --unofficial-watermark: url(https://www.w3.org/StyleSheets/TR/2016/logos/UD-watermark);

    --logo-bg: #1a5e9a;
    --logo-active-bg: #c00;
    --logo-text: white;

    --tocnav-normal-text: #707070;
    --tocnav-normal-bg: var(--bg);
    --tocnav-hover-text: var(--tocnav-normal-text);
    --tocnav-hover-bg: #f8f8f8;
    --tocnav-active-text: #c00;
    --tocnav-active-bg: var(--tocnav-normal-bg);

    --tocsidebar-text: var(--text);
    --tocsidebar-bg: #f7f8f9;
    --tocsidebar-shadow: rgba(0,0,0,.1);
    --tocsidebar-heading-text: hsla(203,20%,40%,.7);

    --toclink-text: var(--text);
    --toclink-underline: #3980b5;
    --toclink-visited-text: var(--toclink-text);
    --toclink-visited-underline: #054572;

    --heading-text: #005a9c;

    --hr-text: var(--text);

    --algo-border: #def;

    --del-text: red;
    --del-bg: transparent;
    --ins-text: #080;
    --ins-bg: transparent;

    --a-normal-text: #034575;
    --a-normal-underline: #bbb;
    --a-visited-text: var(--a-normal-text);
    --a-visited-underline: #707070;
    --a-hover-bg: rgba(75%, 75%, 75%, .25);
    --a-active-text: #c00;
    --a-active-underline: #c00;

    --blockquote-border: silver;
    --blockquote-bg: transparent;
    --blockquote-text: currentcolor;

    --issue-border: #e05252;
    --issue-bg: #fbe9e9;
    --issue-text: var(--text);
    --issueheading-text: #831616;

    --example-border: #e0cb52;
    --example-bg: #fcfaee;
    --example-text: var(--text);
    --exampleheading-text: #574b0f;

    --note-border: #52e052;
    --note-bg: #e9fbe9;
    --note-text: var(--text);
    --noteheading-text: hsl(120, 70%, 30%);
    --notesummary-underline: silver;

    --assertion-border: #aaa;
    --assertion-bg: #eee;
    --assertion-text: black;

    --advisement-border: orange;
    --advisement-bg: #fec;
    --advisement-text: var(--text);
    --advisementheading-text: #b35f00;

    --warning-border: red;
    --warning-bg: hsla(40,100%,50%,0.95);
    --warning-text: var(--text);

    --amendment-border: #330099;
    --amendment-bg: #F5F0FF;
    --amendment-text: var(--text);
    --amendmentheading-text: #220066;

    --def-border: #8ccbf2;
    --def-bg: #def;
    --def-text: var(--text);
    --defrow-border: #bbd7e9;

    --datacell-border: silver;

    --indexinfo-text: #707070;

    --indextable-hover-text: black;
    --indextable-hover-bg: #f7f8f9;

    --outdatedspec-bg: rgba(0, 0, 0, .5);
    --outdatedspec-text: black;
    --outdated-bg: maroon;
    --outdated-text: white;
    --outdated-shadow: red;

    --editedrec-bg: darkorange;
}

@media (prefers-color-scheme: dark) {
    :root {
        --text: #ddd;
        --bg: black;

        --unofficial-watermark: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='400' height='400'%3E%3Cg fill='%23100808' transform='translate(200 200) rotate(-45) translate(-200 -200)' stroke='%23100808' stroke-width='3'%3E%3Ctext x='50%25' y='220' style='font: bold 70px sans-serif; text-anchor: middle; letter-spacing: 6px;'%3EUNOFFICIAL%3C/text%3E%3Ctext x='50%25' y='305' style='font: bold 70px sans-serif; text-anchor: middle; letter-spacing: 6px;'%3EDRAFT%3C/text%3E%3C/g%3E%3C/svg%3E");

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   <h1 class="p-name no-ref" id="title">P2958R0<br><code class="highlight"><c- n>typeof</c-></code> and <code class="highlight"><c- n>typeof_unqual</c-></code> for C++</h1>
   <h2 class="no-num no-toc no-ref heading settled" id="profile-and-date"><span class="content">Published Proposal, <time class="dt-updated" datetime="2023-08-05">2023-08-05</time></span></h2>
   <div data-fill-with="spec-metadata">
    <dl>
     <dt>This version:
     <dd><a class="u-url" href="https://thephd.dev/_vendor/future_cxx/papers/d2958.html">https://thephd.dev/_vendor/future_cxx/papers/d2958.html</a>
     <dt class="editor">Author:
     <dd class="editor p-author h-card vcard"><a class="p-name fn u-email email" href="mailto:phdofthehouse@gmail.com">JeanHeyd Meneide (https://thephd.dev)</a>
     <dt>Audience:
     <dd>EWG
     <dt>Project:
     <dd>ISO/IEC 14882 Programming Languages — C++, ISO/IEC JTC1/SC22/WG21
     <dt>Target:
     <dd>C++26
     <dt>Latest:
     <dd><a href="https://thephd.dev/_vendor/future_cxx/papers/d2958.html">https://thephd.dev/_vendor/future_cxx/papers/d2958.html</a>
    </dl>
   </div>
   <div data-fill-with="warning"></div>
   <hr title="Separator for header">
  </div>
  <div class="p-summary" data-fill-with="abstract">
   <h2 class="no-num no-toc no-ref heading settled" id="abstract"><span class="content">Abstract</span></h2>
   <p>The long-anticipated type features from C have been integrated into C23, and should be ported to WG21 for harmony.</p>
  </div>
  <nav data-fill-with="table-of-contents" id="toc">
   <h2 class="no-num no-toc no-ref" id="contents">Table of Contents</h2>
   <ol class="toc" role="directory">
    <li>
     <a href="#changelog"><span class="secno">1</span> <span class="content">Revision History</span></a>
     <ol class="toc">
      <li><a href="#changelog-r0"><span class="secno">1.1</span> <span class="content">Revision 0 - August 5th, 2023</span></a>
     </ol>
    <li><a href="#intro"><span class="secno">2</span> <span class="content">Introduction and Motivation</span></a>
    <li>
     <a href="#wording"><span class="secno">3</span> <span class="content">Specification</span></a>
     <ol class="toc">
      <li>
       <a href="#wording-language"><span class="secno">3.1</span> <span class="content">Language Wording</span></a>
       <ol class="toc">
        <li><a href="#wording-language-tab:lex.key"><span class="secno">3.1.1</span> <span class="content">Add to Table 5: Keywords (<code class="highlight"><c- p>[</c-><c- n>tab</c-><c- o>:</c-><c- n>lex</c-><c- p>.</c-><c- n>key</c-><c- p>]</c-></code>) 2 new keywords</span></a>
        <li><a href="#wording-language-dcl.type.decltype"><span class="secno">3.1.2</span> <span class="content">Modify "Decltype specifiers" [<span>dcl.type.decltype</span>]</span></a>
        <li><a href="#wording-language-temp.deduct.general"><span class="secno">3.1.3</span> <span class="content">Modify <code class="highlight"><c- k>decltype</c-></code> mention in Template Deduction’s General Clause [<span>temp.deduct.general</span>] to include <code class="highlight"><c- n>typeof</c-></code> and <code class="highlight"><c- n>typeof_unqual</c-></code></span></a>
       </ol>
     </ol>
    <li>
     <a href="#references"><span class="secno"></span> <span class="content">References</span></a>
     <ol class="toc">
      <li><a href="#informative"><span class="secno"></span> <span class="content">Informative References</span></a>
     </ol>
   </ol>
  </nav>
  <main>
   <h2 class="heading settled" data-level="1" id="changelog"><span class="secno">1. </span><span class="content">Revision History</span><a class="self-link" href="#changelog"></a></h2>
   <h3 class="heading settled" data-level="1.1" id="changelog-r0"><span class="secno">1.1. </span><span class="content">Revision 0 - August 5th, 2023</span><a class="self-link" href="#changelog-r0"></a></h3>
   <ul>
    <li data-md>
     <p>Initial Release! 🎉</p>
   </ul>
   <h2 class="heading settled" data-level="2" id="intro"><span class="secno">2. </span><span class="content">Introduction and Motivation</span><a class="self-link" href="#intro"></a></h2>
   <p>In the oldest proposals for <code class="highlight"><c- k>decltype</c-><c- p>(...)</c-></code>, the proposal authors noted how the construct would produce a reference under common situations involving declarations and usage of C code inside of it. This was part of a sincere argument to leave <code class="highlight"><c- n>typeof</c-></code> alone as a keyword and instead pivot to the <code class="highlight"><c- k>decltype</c-></code> keyword instead, with some authors directly pointing out serious flaws with trying to take the <code class="highlight"><c- n>typeof</c-></code> keyword from the existing vendor extension and C implementation space <a data-link-type="biblio" href="#biblio-n2343" title="N2343 - Decltype (revision 7)">[n2343]</a> <a data-link-type="biblio" href="#biblio-n1978" title="N1978 - Decltype (revision 5)">[n1978]</a>.</p>
   <p>The intention was that keyword differed enough from the existing practice from C and C++ compilers with the <code class="highlight"><c- n>typeof</c-></code> and <code class="highlight"><c- n>__typeof__</c-></code> extensions that they should leave it alone, and let C standardize it at its own pace. C23 added <code class="highlight"><c- n>typeof</c-></code> and, at the request of users working on the Linux Kernel and within the GCC bug tracker, <code class="highlight"><c- n>typeof_unqual</c-></code> to solve the distinct issues with C <a data-link-type="biblio" href="#biblio-n2927" title="N2927 - Not-so-magic - typeof for C">[n2927]</a>. Furthermore, it keeps with the existing practice that allows both expressions and type names to go into the <code class="highlight"><c- n>typeof</c-></code> operator in a way that <code class="highlight"><c- k>decltype</c-></code> chose not to.</p>
   <p>Critically, this means that <code class="highlight"><c- n>typeof</c-></code> and <code class="highlight"><c- n>__typeof__</c-></code> cannot be fully approximated with <code class="highlight"><c- k>decltype</c-></code> alone, or even a macro such as <code class="highlight"><c- cp>#define typeof(...) ::std::remove_reference_t&lt;decltype(__VA_ARGS__)></c-></code>. C and C++ implementations the <code class="highlight"><c- n>typeof</c-></code> extension can already take a type specifier (or, more specifically for the case of C++ grammar, a <em>type-id</em>). This is exceptionally important for <code class="highlight"><c- n>typeof</c-></code> usage in macros: often times, rather than inventing an expression with which to provide the right type to a macro, it can be expedient to just pass a type in directly where possible to control the eventual cast or type inside of particularly complex macros. This is done a handful of times in C world. This is not as important for C++, but (some) macros tend to live in a shared world for C and C++.</p>
   <p>Some thought was given whether for this proposal to allow <code class="highlight"><c- k>decltype</c-><c- p>(</c-> <c- n>type</c-><c- o>-</c-><c- n>id</c-> <c- p>)</c-></code> in the grammar as a type-based pass-through. An earlier revisions of <a data-link-type="biblio" href="#biblio-n1978" title="N1978 - Decltype (revision 5)">[n1978]</a> (N1607, to be precise) states, it was left untouched so to let it potentially be used as a "meta"-type value. That paper even casually references the idea of doing <code class="highlight"><c- k>decltype</c-><c- p>(</c-><c- n>SomeType</c-><c- p>).</c-><c- n>is_reference</c-><c- p>()</c-></code>. We believe it is highly unlikely this will ever happen given the direction reflection has gone in for its facilities (e.g. preferring a sigil/operator or the keyword <code class="highlight"><c- n>reflexpr</c-></code>). Furthermore, the overall direction of C++ with <code class="highlight"><c- o>&lt;</c-><c- n>type_traits</c-><c- o>></c-></code> has eschewed the idea that there would ever be a used for <code class="highlight"><c- k>decltype</c-><c- p>(</c-><c- n>SomeType</c-><c- p>)</c-></code> as a <code class="highlight"><c- k>constexpr</c-> <c- n>object</c-></code>-producing object. It could be safe to take <code class="highlight"><c- k>decltype</c-> <c- p>(</c-> <c- n>type</c-><c- o>-</c-><c- n>id</c-> <c- p>)</c-></code> for C++ to just act as a placeholder for <code class="highlight"><c- n>type</c-><c- o>-</c-><c- n>id</c-></code> to harmonize its version of <code class="highlight"><c- n>typeof</c-></code> with C’s, even if it might not provide any essential value.</p>
   <p>But, we do <strong>NOT</strong> propose it here and consider it outside the scope of this proposal as there is no existing practice for <code class="highlight"><c- k>decltype</c-> <c- p>(</c-> <c- n>type</c-><c- o>-</c-><c- n>id</c-> <c- p>)</c-></code>.</p>
   <p>This proposal adds <code class="highlight"><c- n>typeof</c-></code> and <code class="highlight"><c- n>typeof_unqual</c-></code> to C++ to harmonize the 2 languages and close the loophole left from 20 years ago (for C++) and 30 years ago (from C), now that C has finally standardized its long-implemented keyword extensions.</p>
   <h2 class="heading settled" data-level="3" id="wording"><span class="secno">3. </span><span class="content">Specification</span><a class="self-link" href="#wording"></a></h2>
   <p>The specification is relative to the latest C++ Working Draft, <a data-link-type="biblio" href="#biblio-n4950" title="Working Draft, Standard for Programming Language C++">[n4950]</a>.</p>
   <h3 class="heading settled" data-level="3.1" id="wording-language"><span class="secno">3.1. </span><span class="content">Language Wording</span><a class="self-link" href="#wording-language"></a></h3>
   <h4 class="heading settled" data-level="3.1.1" id="wording-language-tab:lex.key"><span class="secno">3.1.1. </span><span class="content">Add to Table 5: Keywords (<code class="highlight"><c- p>[</c-><c- n>tab</c-><c- o>:</c-><c- n>lex</c-><c- p>.</c-><c- n>key</c-><c- p>]</c-></code>) 2 new keywords</span><a class="self-link" href="#wording-language-tab:lex.key"></a></h4>
   <blockquote>
    <div class="wording-section">
     <div class="wording-section-header" id="lex.key"> <span class="wording-clause-number">5.11</span> <span class="wording-clause-title">Keywords</span> <span class="wording-clause-stable-tag">[<b>lex.key</b>]</span> </div>
     <div class="wording-numbered">
      <p>…</p>
      <table>
       <tbody>
        <tr id="tab:lex.key-row-1">
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-1-column-1-sentence-1"><span id=":alignas"><span class="texttt"><span class="keyword">alignas</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-1-column-2-sentence-1"><span id=":constinit"><span class="texttt"><span class="keyword">constinit</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-1-column-3-sentence-1"><span id=":false"><span class="texttt"><span class="literal">false</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-1-column-4-sentence-1"><span id=":public"><span class="texttt"><span class="keyword">public</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-1-column-5-sentence-1"><span id=":true"><span class="texttt"><span class="literal">true</span></span></span></div>
          </div>
        <tr id="tab:lex.key-row-2">
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-2-column-1-sentence-1"><span id=":alignof"><span class="texttt"><span class="keyword">alignof</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-2-column-2-sentence-1"><span id=":const_cast"><span class="texttt"><span class="keyword">const_<span class="shy"></span>cast</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-2-column-3-sentence-1"><span id=":float"><span class="texttt"><span class="keyword">float</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-2-column-4-sentence-1"><span id=":register_"><span class="texttt"><span class="keyword">register</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-2-column-5-sentence-1"><span id=":try"><span class="texttt"><span class="keyword">try</span></span></span></div>
          </div>
        <tr id="tab:lex.key-row-3">
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-3-column-1-sentence-1"><span id=":asm"><span class="texttt"><span class="keyword">asm</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-3-column-2-sentence-1"><span id=":continue"><span class="texttt"><span class="keyword">continue</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-3-column-3-sentence-1"><span id=":for"><span class="texttt"><span class="keyword">for</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-3-column-4-sentence-1"><span id=":reinterpret_cast"><span class="texttt"><span class="keyword">reinterpret_<span class="shy"></span>cast</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-3-column-5-sentence-1"><span id=":typedef"><span class="texttt"><span class="keyword">typedef</span></span></span></div>
          </div>
        <tr id="tab:lex.key-row-4">
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-4-column-1-sentence-1"><span id=":auto"><span class="texttt"><span class="keyword">auto</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-4-column-2-sentence-1"><span id=":co_await"><span class="texttt"><span class="keyword">co_<span class="shy"></span>await</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-4-column-3-sentence-1"><span id=":friend"><span class="texttt"><span class="keyword">friend</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-4-column-4-sentence-1"><span id=":requires"><span class="texttt"><span class="keyword">requires</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-4-column-5-sentence-1"><span id=":typeid"><span class="texttt"><span class="keyword">typeid</span></span></span></div>
          </div>
        <tr id="tab:lex.key-row-5">
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-5-column-1-sentence-1"><span id=":bool"><span class="texttt"><span class="keyword">bool</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-5-column-2-sentence-1"><span id=":co_return"><span class="texttt"><span class="keyword">co_<span class="shy"></span>return</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-5-column-3-sentence-1"><span id=":goto"><span class="texttt"><span class="keyword">goto</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-5-column-4-sentence-1"><span id=":return"><span class="texttt"><span class="keyword">return</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-5-column-5-sentence-1"><span id=":typename"><span class="texttt"><span class="keyword">typename</span></span></span></div>
          </div>
        <tr id="tab:lex.key-row-6">
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-6-column-1-sentence-1"><span id=":break"><span class="texttt"><span class="keyword">break</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-6-column-2-sentence-1"><span id=":co_yield"><span class="texttt"><span class="keyword">co_<span class="shy"></span>yield</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-6-column-3-sentence-1"><span id=":if"><span class="texttt"><span class="keyword">if</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-6-column-4-sentence-1"><span id=":short"><span class="texttt"><span class="keyword">short</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-6-column-5-sentence-1"><span id=":typeof"><span class="texttt"><span class="keyword"><ins>typeof</ins></span></span></span></div>
          </div>
        <tr id="tab:lex.key-row-7">
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-7-column-1-sentence-1"><span id=":case"><span class="texttt"><span class="keyword">case</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-7-column-2-sentence-1"><span id=":decltype"><span class="texttt"><span class="keyword">decltype</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-7-column-3-sentence-1"><span id=":inline"><span class="texttt"><span class="keyword">inline</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-7-column-4-sentence-1"><span id=":signed"><span class="texttt"><span class="keyword">signed</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-7-column-5-sentence-1"><span id=":typeof_unqual"><span class="texttt"><span class="keyword"><ins>typeof_unqual</ins></span></span></span></div>
          </div>
        <tr id="tab:lex.key-row-8">
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-8-column-1-sentence-1"><span id=":catch"><span class="texttt"><span class="keyword">catch</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-8-column-2-sentence-1"><span id=":default"><span class="texttt"><span class="keyword">default</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-8-column-3-sentence-1"><span id=":int"><span class="texttt"><span class="keyword">int</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-8-column-4-sentence-1"><span id=":sizeof"><span class="texttt"><span class="keyword">sizeof</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-8-column-5-sentence-1"><span id=":…"><span class="texttt"><span class="keyword">…</span></span></span></div>
          </div>
        <tr id="tab:lex.key-row-9">
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-9-column-1-sentence-1"><span id=":char"><span class="texttt"><span class="keyword">char</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-9-column-2-sentence-1"><span id=":delete"><span class="texttt"><span class="keyword">delete</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-9-column-3-sentence-1"><span id=":long"><span class="texttt"><span class="keyword">long</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-9-column-4-sentence-1"><span id=":static"><span class="texttt"><span class="keyword">static</span></span></span></div>
          </div>
        <tr id="tab:lex.key-row-10">
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-10-column-1-sentence-1"><span id=":char8_t"><span class="texttt"><span class="keyword">char8_<span class="shy"></span>t</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-10-column-2-sentence-1"><span id=":do"><span class="texttt"><span class="keyword">do</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-10-column-3-sentence-1"><span id=":mutable"><span class="texttt"><span class="keyword">mutable</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-10-column-4-sentence-1"><span id=":static_assert"><span class="texttt"><span class="keyword">static_<span class="shy"></span>assert</span></span></span></div>
          </div>
        <tr id="tab:lex.key-row-11">
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-11-column-1-sentence-1"><span id=":char16_t"><span class="texttt"><span class="keyword">char16_<span class="shy"></span>t</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-11-column-2-sentence-1"><span id=":double"><span class="texttt"><span class="keyword">double</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-11-column-3-sentence-1"><span id=":namespace"><span class="texttt"><span class="keyword">namespace</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-11-column-4-sentence-1"><span id=":static_cast"><span class="texttt"><span class="keyword">static_<span class="shy"></span>cast</span></span></span></div>
          </div>
        <tr id="tab:lex.key-row-12">
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-12-column-1-sentence-1"><span id=":char32_t"><span class="texttt"><span class="keyword">char32_<span class="shy"></span>t</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-12-column-2-sentence-1"><span id=":dynamic_cast"><span class="texttt"><span class="keyword">dynamic_<span class="shy"></span>cast</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-12-column-3-sentence-1"><span id=":new"><span class="texttt"><span class="keyword">new</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-12-column-4-sentence-1"><span id=":struct"><span class="texttt"><span class="keyword">struct</span></span></span></div>
          </div>
        <tr id="tab:lex.key-row-13">
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-13-column-1-sentence-1"><span id=":class"><span class="texttt"><span class="keyword">class</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-13-column-2-sentence-1"><span id=":else"><span class="texttt"><span class="keyword">else</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-13-column-3-sentence-1"><span id=":noexcept"><span class="texttt"><span class="keyword">noexcept</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-13-column-4-sentence-1"><span id=":switch"><span class="texttt"><span class="keyword">switch</span></span></span></div>
          </div>
        <tr id="tab:lex.key-row-14">
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-14-column-1-sentence-1"><span id=":concept"><span class="texttt"><span class="keyword">concept</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-14-column-2-sentence-1"><span id=":enum"><span class="texttt"><span class="keyword">enum</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-14-column-3-sentence-1"><span id=":nullptr"><span class="texttt"><span class="literal">nullptr</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-14-column-4-sentence-1"><span id=":template"><span class="texttt"><span class="keyword">template</span></span></span></div>
          </div>
         <td class="empty left">
        <tr id="tab:lex.key-row-15">
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-15-column-1-sentence-1"><span id=":const"><span class="texttt"><span class="keyword">const</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-15-column-2-sentence-1"><span id=":explicit"><span class="texttt"><span class="keyword">explicit</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-15-column-3-sentence-1"><span id=":operator"><span class="texttt"><span class="keyword">operator</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-15-column-4-sentence-1"><span id=":this"><span class="texttt"><span class="keyword">this</span></span></span></div>
          </div>
         <td class="empty left">
        <tr id="tab:lex.key-row-16">
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-16-column-1-sentence-1"><span id=":consteval"><span class="texttt"><span class="keyword">consteval</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-16-column-2-sentence-1"><span id=":export"><span class="texttt"><span class="keyword">export</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-16-column-3-sentence-1"><span id=":private"><span class="texttt"><span class="keyword">private</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-16-column-4-sentence-1"><span id=":thread_local"><span class="texttt"><span class="keyword">thread_<span class="shy"></span>local</span></span></span></div>
          </div>
         <td class="empty left">
        <tr id="tab:lex.key-row-17">
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-17-column-1-sentence-1"><span id=":constexpr"><span class="texttt"><span class="keyword">constexpr</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-17-column-2-sentence-1"><span id=":extern"><span class="texttt"><span class="keyword">extern</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-17-column-3-sentence-1"><span id=":protected"><span class="texttt"><span class="keyword">protected</span></span></span></div>
          </div>
         <td class="left">
          <div class="texpara">
           <div class="sentence" id="tab:lex.key-row-17-column-4-sentence-1"><span id=":throw"><span class="texttt"><span class="keyword">throw</span></span></span></div>
          </div>
         <td class="empty left">
      </table>
     </div>
    </div>
   </blockquote>
   <h4 class="heading settled" data-level="3.1.2" id="wording-language-dcl.type.decltype"><span class="secno">3.1.2. </span><span class="content">Modify "Decltype specifiers" [<a href="https://eel.is/c++draft/dcl.type.decltype">dcl.type.decltype</a>]</span><a class="self-link" href="#wording-language-dcl.type.decltype"></a></h4>
   <blockquote>
    <div class="wording-section">
     <div class="wording-section-header" id="dcl.type.decltype"> <span class="wording-clause-number">9.2.9.5</span> <span class="wording-clause-title">Decltype specifiers</span> <span class="wording-clause-stable-tag">[<b>dcl.type.decltype</b>]</span> </div>
     <p><em>decltype-specifier</em>:</p>
     <dl>
      <dd data-md>
       <p><code class="highlight"><c- k>decltype</c-></code> <code class="highlight"><c- p>(</c-></code> <em>expression</em> <code class="highlight"><c- p>)</c-></code></p>
      <dd data-md>
       <ins><code class="highlight"><c- n>typeof</c-></code> <code class="highlight"><c- p>(</c-></code> <em>expression</em> <code class="highlight"><c- p>)</c-></code></ins>
      <dd data-md>
       <ins><code class="highlight"><c- n>typeof</c-></code> <code class="highlight"><c- p>(</c-></code> <em>type-id</em> <code class="highlight"><c- p>)</c-></code></ins>
      <dd data-md>
       <ins><code class="highlight"><c- n>typeof_unqual</c-></code> <code class="highlight"><c- p>(</c-></code> <em>expression</em> <code class="highlight"><c- p>)</c-></code></ins>
      <dd data-md>
       <ins><code class="highlight"><c- n>typeof_unqual</c-></code> <code class="highlight"><c- p>(</c-></code> <em>type-id</em> <code class="highlight"><c- p>)</c-></code></ins>
     </dl>
     <div class="wording-numbered">
      <p>For an <code class="highlight"><c- n>expression</c-></code> <em>E</em>, the type denoted by <code class="highlight"><c- k>decltype</c-><c- p>(</c-><c- n>E</c-><c- p>)</c-></code> is defined as follows:</p>
      <div class="wording-numbered-list">
       <ul>
        <li>if E is an unparenthesized <em>id-expression</em> naming a structured binding (<a href="http://eel.is/c++draft/dcl.struct.bind">[dcl.struct.bind</a>]), <code class="highlight"><c- k>decltype</c-><c- p>(</c-><c- n>E</c-><c- p>)</c-></code> is the referenced type as given in the specification of the structured binding declaration;
        <li>otherwise, if <em>E</em> is an unparenthesized <em>id-expression</em> naming a non-type template-parameter (<a href="http://eel.is/c++draft/temp.param">[temp.param</a>]), <code class="highlight"><c- k>decltype</c-><c- p>(</c-><c- n>E</c-><c- p>)</c-></code> is the type of the template-parameter after performing any necessary type deduction (<a href="http://eel.is/c++draft/dcl.spec.auto">[dcl.spec.auto</a>], <a href="http://eel.is/c++draft/dcl.type.class.deduct">[dcl.type.class.deduct</a>]);
        <li>otherwise, if <em>E</em> is an unparenthesized <em>id-expression</em> or an unparenthesized class member access (<a href="http://eel.is/c++draft/expr.ref">[expr.ref</a>]), <code class="highlight"><c- k>decltype</c-><c- p>(</c-><c- n>E</c-><c- p>)</c-></code> is the type of the entity named by <em>E</em>.
         If there is no such entity, the program is ill-formed; 
        <li>otherwise, if <em>E</em> is an xvalue, <code class="highlight"><c- k>decltype</c-><c- p>(</c-><c- n>E</c-><c- p>)</c-></code> is <code class="highlight"><c- n>T</c-><c- o>&amp;&amp;</c-></code>, where <code class="highlight"><c- n>T</c-></code> is the type of <em>E</em>;
        <li>otherwise, if <em>E</em> is an lvalue, <code class="highlight"><c- k>decltype</c-><c- p>(</c-><c- n>E</c-><c- p>)</c-></code> is <code class="highlight"><c- n>T</c-><c- o>&amp;</c-></code>, where <code class="highlight"><c- n>T</c-></code> is the type of <em>E</em>;
        <li>otherwise, <code class="highlight"><c- k>decltype</c-><c- p>(</c-><c- n>E</c-><c- p>)</c-></code> is the type of <em>E</em>.
       </ul>
      </div>
      <p>
       The operand of the <code class="highlight"><c- k>decltype</c-></code>
       <ins>, <code class="highlight"><c- n>typeof</c-></code>, or <code class="highlight"><c- n>typeof_unqual</c-></code></ins>
        specifier is an unevaluated operand.
      </p>
     </div>
     <div> … </div>
     <div class="wording-newnumbered wording-numbered-3">
      <ins>
       <p>For an expression <em>E</em>, the type denoted by <code class="highlight"><c- n>typeof</c-><c- p>(</c-><c- n>E</c-><c- p>)</c-></code> is formed by removing reference qualifiers, if any, from the type denoted by <code class="highlight"><c- k>decltype</c-><c- p>(</c-><c- n>E</c-><c- p>)</c-></code>. The type denoted by <code class="highlight"><c- n>typeof_unqual</c-><c- p>(</c-><c- n>E</c-><c- p>)</c-></code> is formed by removing reference qualifiers, if any, as well as top-level cv-qualifiers from the type denoted by <code class="highlight"><c- k>decltype</c-><c- p>(</c-><c- n>E</c-><c- p>)</c-></code>.</p>
      </ins>
     </div>
     <div class="wording-newnumbered">
      <ins>
       <p>For a <em>type-id</em> <code class="highlight"><c- n>T</c-></code>, the type denoted by <code class="highlight"><c- n>typeof</c-><c- p>(</c-><c- n>T</c-><c- p>)</c-></code> is formed by removing reference qualifiers, if any, from <code class="highlight"><c- n>T</c-></code>. The type denoted by <code class="highlight"><c- n>typeof_unqual</c-><c- p>(</c-><c- n>T</c-><c- p>)</c-></code> is formed by removing reference qualifiers, if any, as well as top-level cv-qualifiers from <code class="highlight"><c- n>T</c-></code>.</p>
      </ins>
     </div>
    </div>
   </blockquote>
   <h4 class="heading settled" data-level="3.1.3" id="wording-language-temp.deduct.general"><span class="secno">3.1.3. </span><span class="content">Modify <code class="highlight"><c- k>decltype</c-></code> mention in Template Deduction’s General Clause [<a href="http://eel.is/c++draft/temp.deduct.general">temp.deduct.general</a>] to include <code class="highlight"><c- n>typeof</c-></code> and <code class="highlight"><c- n>typeof_unqual</c-></code></span><a class="self-link" href="#wording-language-temp.deduct.general"></a></h4>
   <blockquote>
    <div class="wording-section">
     <div class="wording-section-header" id="temp.deduct.general"> <span class="wording-clause-number">13.10.3.1</span> <span class="wording-clause-title">General</span> <span class="wording-clause-stable-tag">[<b>temp.deduct.general</b>]</span> </div>
     <div> … </div>
     <div class="wording-numbered wording-numbered-6">
      <p>The deduction substitution loci are</p>
      <div class="wording-numbered-list">
       <ul>
        <li>the function type outside of the <em>noexcept-specifier</em>,
        <li>the <em>explicit-specifier</em>, and
        <li>the template parameter declarations.
       </ul>
      </div>
      <p>
       The substitution occurs in all types and expressions that are used in the deduction substitution loci.
The expressions include not only constant expressions such as those that appear in array bounds or as nontype template arguments but also general expressions (i.e., non-constant expressions) inside <code class="highlight"><c- k>sizeof</c-></code>, <code class="highlight"><c- k>decltype</c-></code>,
       <ins><code class="highlight"><c- n>typeof</c-></code>, <code class="highlight"><c- n>typeof_unqual</c-></code>,</ins>
        and other contexts that allow non-constant expressions. The substitution proceeds in lexical order and stops when a condition that causes deduction to fail is encountered. If substitution into different declarations of the same function template would cause template instantiations to occur in a different order or not at all, the program is ill-formed; no diagnostic required.
      </p>
     </div>
     <div> … </div>
    </div>
   </blockquote>
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  <h2 class="no-num no-ref heading settled" id="references"><span class="content">References</span><a class="self-link" href="#references"></a></h2>
  <h3 class="no-num no-ref heading settled" id="informative"><span class="content">Informative References</span><a class="self-link" href="#informative"></a></h3>
  <dl>
   <dt id="biblio-n1978">[N1978]
   <dd>Jakko Järvi; Bjarne Stroustrup; Gabriel Dos Reis. <a href="https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2006/n1978.pdf"><cite>N1978 - Decltype (revision 5)</cite></a>. April 24th, 2006. URL: <a href="https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2006/n1978.pdf">https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2006/n1978.pdf</a>
   <dt id="biblio-n2343">[N2343]
   <dd>Jakko Järvi; Bjarne Stroustrup; Gabriel Dos Reis. <a href="https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2343.pdf"><cite>N2343 - Decltype (revision 7)</cite></a>. July 18th, 2007. URL: <a href="https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2343.pdf">https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2343.pdf</a>
   <dt id="biblio-n2927">[N2927]
   <dd>JeanHeyd Meneide; Shepherd's Oasis, LLC. <a href="https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2927.htm"><cite>N2927 - Not-so-magic - typeof for C</cite></a>. July 18th, 2007. URL: <a href="https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2927.htm">https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2927.htm</a>
   <dt id="biblio-n4950">[N4950]
   <dd>Thomas Köppe. <a href="https://wg21.link/n4950"><cite>Working Draft, Standard for Programming Language C++</cite></a>. 10 May 2023. URL: <a href="https://wg21.link/n4950">https://wg21.link/n4950</a>
  </dl>