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  <title>P3468R0: 2024-10 Library Evolution Poll Outcomes</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;
		}
	}
	/* 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>
<style>
    table, th, td {
      border: 1px solid black;
      border-collapse: collapse;
      vertical-align: top;
    }
    th, td {
      border-left: none;
      border-right: none;
      padding: 0px 10px;
    }
    th {
      text-align: center;
    }

    del { background: #fcc; color: #000; text-decoration: line-through; }
    ins { background: #cfc; color: #000; }
    blockquote .highlight:not(.idl) { background: initial; margin: initial; padding: 0.5em }
    blockquote ul { background: inherit; }
    blockquote code.highlight:not(.idl) { padding: initial; }
    blockquote c-[a] { color: inherit; } /* Keyword.Declaration */
    blockquote c-[b] { color: inherit; } /* Keyword.Type */
    blockquote c-[c] { color: inherit; } /* Comment */
    blockquote c-[d] { color: inherit; } /* Comment.Multiline */
    blockquote c-[e] { color: inherit; } /* Name.Attribute */
    blockquote c-[f] { color: inherit; } /* Name.Tag */
    blockquote c-[g] { color: inherit; } /* Name.Variable */
    blockquote c-[k] { color: inherit; } /* Keyword */
    blockquote c-[l] { color: inherit; } /* Literal */
    blockquote c-[m] { color: inherit; } /* Literal.Number */
    blockquote c-[n] { color: inherit; } /* Name */
    blockquote c-[o] { color: inherit; } /* Operator */
    blockquote c-[p] { color: inherit; } /* Punctuation */
    blockquote c-[s] { color: inherit; } /* Literal.String */
    blockquote c-[t] { color: inherit; } /* Literal.String.Single */
    blockquote c-[u] { color: inherit; } /* Literal.String.Double */
    blockquote c-[cp] { color: inherit; } /* Comment.Preproc */
    blockquote c-[c1] { color: inherit; } /* Comment.Single */
    blockquote c-[cs] { color: inherit; } /* Comment.Special */
    blockquote c-[kc] { color: inherit; } /* Keyword.Constant */
    blockquote c-[kn] { color: inherit; } /* Keyword.Namespace */
    blockquote c-[kp] { color: inherit; } /* Keyword.Pseudo */
    blockquote c-[kr] { color: inherit; } /* Keyword.Reserved */
    blockquote c-[ld] { color: inherit; } /* Literal.Date */
    blockquote c-[nc] { color: inherit; } /* Name.Class */
    blockquote c-[no] { color: inherit; } /* Name.Constant */
    blockquote c-[nd] { color: inherit; } /* Name.Decorator */
    blockquote c-[ni] { color: inherit; } /* Name.Entity */
    blockquote c-[ne] { color: inherit; } /* Name.Exception */
    blockquote c-[nf] { color: inherit; } /* Name.Function */
    blockquote c-[nl] { color: inherit; } /* Name.Label */
    blockquote c-[nn] { color: inherit; } /* Name.Namespace */
    blockquote c-[py] { color: inherit; } /* Name.Property */
    blockquote c-[ow] { color: inherit; } /* Operator.Word */
    blockquote c-[mb] { color: inherit; } /* Literal.Number.Bin */
    blockquote c-[mf] { color: inherit; } /* Literal.Number.Float */
    blockquote c-[mh] { color: inherit; } /* Literal.Number.Hex */
    blockquote c-[mi] { color: inherit; } /* Literal.Number.Integer */
    blockquote c-[mo] { color: inherit; } /* Literal.Number.Oct */
    blockquote c-[sb] { color: inherit; } /* Literal.String.Backtick */
    blockquote c-[sc] { color: inherit; } /* Literal.String.Char */
    blockquote c-[sd] { color: inherit; } /* Literal.String.Doc */
    blockquote c-[se] { color: inherit; } /* Literal.String.Escape */
    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 */
  </style>
  <meta content="Bikeshed version ac5ea272d, updated Fri Dec 6 15:45:15 2024 -0800" name="generator">
  <link href="https://wg21.link/P3468" rel="canonical">
  <link href="https://isocpp.org/favicon.ico" rel="icon">
  <meta content="dark light" name="color-scheme">
<style>/* Boilerplate: style-autolinks */
.css.css, .property.property, .descriptor.descriptor {
    color: var(--a-normal-text);
    font-size: inherit;
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  <div class="head">
   <p data-fill-with="logo"></p>
   <h1 class="p-name no-ref" id="title">P3468R0<br>2024-10 Library Evolution Poll Outcomes</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="2024-12-16">2024-12-16</time></span></h2>
   <div data-fill-with="spec-metadata">
    <dl>
     <dt class="editor">Authors:
     <dd class="editor p-author h-card vcard"><a class="p-name fn u-email email" href="mailto:sinbal2l@gmail.com">Inbal Levi - Library Evolution Chair</a> (<span class="p-org org">MPGC Services LTD</span>)
     <dd class="editor p-author h-card vcard"><a class="p-name fn u-email email" href="mailto:fabio@fracassi.de">Fabio Fracassi - Library Evolution Assistant Chair</a> (<span class="p-org org">CODE University of Applied Sciences</span>)
     <dd class="editor p-author h-card vcard"><a class="p-name fn u-email email" href="mailto:ben.craig@gmail.com">Ben Craig - Library Evolution Assistant Chair</a> (<span class="p-org org">Raven</span>)
     <dd class="editor p-author h-card vcard"><a class="p-name fn u-email email" href="mailto:billy.baker.cpp@gmail.com">Billy Baker - Library Evolution Incubator Chair</a> (<span class="p-org org">NVIDIA</span>)
     <dd class="editor p-author h-card vcard"><a class="p-name fn u-email email" href="mailto:nevin@cplusplusguy.com">Nevin Liber - Library Evolution Incubator Assistant Chair and Admin Chair</a> (<span class="p-org org">Argonne National Laboratory</span>)
     <dd class="editor p-author h-card vcard"><a class="p-name fn u-email email" href="mailto:corentin.jabot@gmail.com">Corentin Jabot - Library Mailing List Review Manager</a>
     <dt>Source:
     <dd><a href="https://github.com/inbal2l/wg21_library_evolution_polls_outcome_script/blob/main/2024_10_library_evolution_poll_outcomes.bs">GitHub</a>
     <dt>Project:
     <dd>ISO/IEC 14882 Programming Languages — C++, ISO/IEC JTC1/SC22/WG21
     <dt>Audience:
     <dd>WG21
    </dl>
   </div>
   <div data-fill-with="warning"></div>
   <hr title="Separator for header">
  </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="#introduction"><span class="secno">1</span> <span class="content">Introduction</span></a>
    <li><a href="#poll-outcomes"><span class="secno">2</span> <span class="content">Poll Outcomes</span></a>
    <li>
     <a href="#poll-comments"><span class="secno">3</span> <span class="content">Selected Poll Comments</span></a>
     <ol class="toc">
      <li><a href="#poll-1-send-p2897r5-aligned_accessor-an-mdspan-accessor-expressing-pointer-overalignment-to-library-working-group-for-c26"><span class="secno">3.1</span> <span class="content">Poll 1: Send "[P2897R5] aligned_accessor: An mdspan accessor expressing pointer overalignment" to Library Working Group for C++26.</span></a>
      <li><a href="#poll-2-send-p3008r2-atomic-floating-point-min-max-to-library-working-group-for-c26"><span class="secno">3.2</span> <span class="content">Poll 2: Send "[P3008R2] Atomic floating-point min/max" to Library Working Group for C++26.</span></a>
      <li><a href="#poll-3-send-p3050r2-fix-c26-by-optimizing-linalgconjugated-for-noncomplex-value-types-to-library-working-group-for-c26"><span class="secno">3.3</span> <span class="content">Poll 3: Send "[P3050R2] Fix C++26 by optimizing linalg::conjugated for noncomplex value types" to Library Working Group for C++26.</span></a>
      <li><a href="#poll-4-send-p3068r4-allowing-exception-throwing-in-constant-evaluation-to-library-working-group-for-c26"><span class="secno">3.4</span> <span class="content">Poll 4: Send "[P3068R4] Allowing exception throwing in constant-evaluation" to Library Working Group for C++26.</span></a>
      <li><a href="#poll-5-send-p3136r0-retiring-niebloids-to-library-working-group-for-c26"><span class="secno">3.5</span> <span class="content">Poll 5: Send "[P3136R0] Retiring niebloids" to Library Working Group for C++26.</span></a>
      <li><a href="#poll-6-send-p3222r0-fix-c26-by-adding-transposed-special-cases-for-p2642-layouts-to-library-working-group-for-c26"><span class="secno">3.6</span> <span class="content">Poll 6: Send "[P3222R0] Fix C++26 by adding transposed special cases for P2642 layouts" to Library Working Group for C++26.</span></a>
      <li><a href="#poll-7-send-p3309r2-constexpr-atomic-and-atomic_ref-to-library-working-group-for-c26"><span class="secno">3.7</span> <span class="content">Poll 7: Send "[P3309R2] constexpr atomic and atomic_ref" to Library Working Group for C++26.</span></a>
      <li><a href="#poll-8-send-p3323r0-cv-qualified-types-in-atomic-and-atomic_ref-to-library-working-group-for-c26"><span class="secno">3.8</span> <span class="content">Poll 8: Send "[P3323R0] cv-qualified types in atomic and atomic_ref" to Library Working Group for C++26.</span></a>
      <li><a href="#poll-9-send-p3325r3-a-utility-for-creating-execution-environments-to-library-working-group-for-c26"><span class="secno">3.9</span> <span class="content">Poll 9: Send "[P3325R3] A Utility for Creating Execution Environments" to Library Working Group for C++26.</span></a>
      <li><a href="#poll-10-send-p0472r2-put-stdmonostate-in--to-library-working-group-for-c26"><span class="secno">3.10</span> <span class="content">Poll 10: Send "[P0472R2] Put std::monostate in <utility>" to Library Working Group for C++26.</utility></span></a>
      <li><a href="#poll-11-send-p3355r1-fix-submdspan-for-c26-to-library-working-group-for-c26"><span class="secno">3.11</span> <span class="content">Poll 11: Send "[P3355R1] Fix submdspan for C++26" to Library Working Group for C++26.</span></a>
      <li><a href="#poll-12-send-p3369r0-constexpr-for-uninitialized_default_construct-to-library-working-group-for-c26"><span class="secno">3.12</span> <span class="content">Poll 12: Send "[P3369R0] constexpr for uninitialized_default_construct" to Library Working Group for C++26.</span></a>
      <li><a href="#poll-13-approve-p3399r0-adjusting-electronic-polls-to-a-hybrid-workflow-and-apply-the-change-to-the-process-of-library-evolution-working-group"><span class="secno">3.13</span> <span class="content">Poll 13: Approve "[P3399R0] Adjusting Electronic Polls to a Hybrid Workflow" and apply the change to the process of Library Evolution Working Group.</span></a>
     </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="introduction"><span class="secno">1. </span><span class="content">Introduction</span><a class="self-link" href="#introduction"></a></h2>
   <p>In 2024-10, the C++ Library Evolution group conducted a series of electronic decision polls <a data-link-type="biblio" href="https://wg21.link/p3467r0" title="2024-10 Library Evolution Polls">[P3467R0]</a>.
This paper provides the results of those polls and summarizes the results.</p>
   <p>In total, 21 people participated in the polls.
Some participants opted to not vote on some polls (lower participation was at: P2897R5, P3050R2, P3222R0, P3355R1)
Thank you to everyone who participated, and to the papers' authors for all their hard work!</p>
   <h2 class="heading settled" data-level="2" id="poll-outcomes"><span class="secno">2. </span><span class="content">Poll Outcomes</span><a class="self-link" href="#poll-outcomes"></a></h2>
   <ul>
    <li data-md>
     <p>SF: Strongly Favor.</p>
    <li data-md>
     <p>WF: Weakly Favor.</p>
    <li data-md>
     <p>N: Neutral.</p>
    <li data-md>
     <p>WA: Weakly Against.</p>
    <li data-md>
     <p>SA: Strongly Against.</p>
   </ul>
   <table>
    <tbody>
     <tr>
      <th>Poll 
      <th>SF 
      <th>WF 
      <th>N 
      <th>WA 
      <th>SA 
      <th>Outcome 
     <tr>
      <td> Poll 1: Send "[P2897R5] aligned_accessor: An mdspan accessor expressing pointer overalignment" to Library Working Group for C++26. 
      <td>9 
      <td>3 
      <td>0 
      <td>0 
      <td>0 
      <td>Strong consensus in favor 
     <tr>
      <td> Poll 2: Send "[P3008R2] Atomic floating-point min/max" to Library Working Group for C++26. 
      <td>7 
      <td>4 
      <td>3 
      <td>0 
      <td>1 
      <td>Consensus in favor 
     <tr>
      <td> Poll 3: Send "[P3050R2] Fix C++26 by optimizing linalg::conjugated for noncomplex value types" to Library Working Group for C++26. 
      <td>9 
      <td>2 
      <td>0 
      <td>0 
      <td>0 
      <td>Strong consensus in favor 
     <tr>
      <td> Poll 4: Send "[P3068R4] Allowing exception throwing in constant-evaluation" to Library Working Group for C++26. 
      <td>13 
      <td>3 
      <td>0 
      <td>1 
      <td>0 
      <td>Consensus in favor 
     <tr>
      <td> Poll 5: Send "[P3136R0] Retiring niebloids" to Library Working Group for C++26. 
      <td>10 
      <td>4 
      <td>0 
      <td>1 
      <td>1 
      <td>Consensus in favor 
     <tr>
      <td> Poll 6: Send "[P3222R0] Fix C++26 by adding transposed special cases for P2642 layouts" to Library Working Group for C++26. 
      <td>7 
      <td>3 
      <td>0 
      <td>0 
      <td>0 
      <td>Strong consensus in favor 
     <tr>
      <td> Poll 7: Send "[P3309R2] constexpr atomic and atomic_ref" to Library Working Group for C++26. 
      <td>11 
      <td>6 
      <td>1 
      <td>1 
      <td>0 
      <td>Consensus in favor 
     <tr>
      <td> Poll 8: Send "[P3323R0] cv-qualified types in atomic and atomic_ref" to Library Working Group for C++26. 
      <td>9 
      <td>8 
      <td>1 
      <td>1 
      <td>0 
      <td>Consensus in favor 
     <tr>
      <td> Poll 9: Send "[P3325R3] A Utility for Creating Execution Environments" to Library Working Group for C++26. 
      <td>7 
      <td>5 
      <td>3 
      <td>0 
      <td>0 
      <td>Strong consensus in favor 
     <tr>
      <td>
        Poll 10: Send "[P0472R2] Put std::monostate in 
       <utility>" to Library Working Group for C++26. </utility>
      <td>10 
      <td>5 
      <td>4 
      <td>0 
      <td>0 
      <td>Strong consensus in favor 
     <tr>
      <td> Poll 11: Send "[P3355R1] Fix submdspan for C++26" to Library Working Group for C++26. 
      <td>8 
      <td>3 
      <td>0 
      <td>0 
      <td>0 
      <td>Strong consensus in favor 
     <tr>
      <td> Poll 12: Send "[P3369R0] constexpr for uninitialized_default_construct" to Library Working Group for C++26. 
      <td>16 
      <td>3 
      <td>0 
      <td>0 
      <td>0 
      <td>Strong consensus in favor 
     <tr>
      <td> Poll 13: Approve "[P3399R0] Adjusting Electronic Polls to a Hybrid Workflow" and apply the change to the process of Library Evolution Working Group. 
      <td>11 
      <td>4 
      <td>1 
      <td>2 
      <td>1 
      <td>Consensus in favor 
   </table>
   <p>All the polls have consensus in favor and will be forwarded to LWG for C++26, accept from P3399R0 which will be applied to modify LEWG procedure.</p>
   <h2 class="heading settled" data-level="3" id="poll-comments"><span class="secno">3. </span><span class="content">Selected Poll Comments</span><a class="self-link" href="#poll-comments"></a></h2>
   <p>For some of the comments, small parts were removed to anonymize.</p>
   <h3 class="heading settled" data-level="3.1" id="poll-1-send-p2897r5-aligned_accessor-an-mdspan-accessor-expressing-pointer-overalignment-to-library-working-group-for-c26"><span class="secno">3.1. </span><span class="content">Poll 1: Send "[P2897R5] aligned_accessor: An mdspan accessor expressing pointer overalignment" to Library Working Group for C++26.</span><a class="self-link" href="#poll-1-send-p2897r5-aligned_accessor-an-mdspan-accessor-expressing-pointer-overalignment-to-library-working-group-for-c26"></a></h3>
   <blockquote>
    <p>The paper is very well-written and explains the rationale and technical bits with very high quality. It’s another good example of well-done homework.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>This feature lets mdspan users express that the beginning of an array (not necessarily even a multidimensional array -- it works for rank-1 arrays too) is overaligned. This lets users express interface and hardware requirements, and also exposes optimization opportunities to compilers.
The design discussion at St. Louis helped clarify mdspan’s opportunities to improve safety in realistic ways.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Much of mdspan’s utility is tied up in being easily vectorizable, so this paper makes sense to go to C++26.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <h3 class="heading settled" data-level="3.2" id="poll-2-send-p3008r2-atomic-floating-point-min-max-to-library-working-group-for-c26"><span class="secno">3.2. </span><span class="content">Poll 2: Send "[P3008R2] Atomic floating-point min/max" to Library Working Group for C++26.</span><a class="self-link" href="#poll-2-send-p3008r2-atomic-floating-point-min-max-to-library-working-group-for-c26"></a></h3>
   <blockquote>
    <p>This exposes a feature increasingly accelerated in hardware, while at the same time clarifying the behavior of min and max with respect to floating-point numbers.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Small but useful utility, that is hard to provide outside of the standard.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>Seems like the technical problems of earlier approaches have been solved. I can’t find any mention of implementation experience in the paper, so N instead of WF.</p>
    <p>— Neutral</p>
   </blockquote>
   <blockquote>
    <p>The provided semantic still does not guarantee that two treads calling fetch_min with arguments -0 and +0 in a loop, will not produce a spin loop, by replacing each other results.
I.e. due unspecified ordering, we may end up in situation where:
Thread 1: writes -0
Thread 2: writes +0
Thread 1: writes -0
Thread 2: writes +0</p>
    <p>— Strongly Against</p>
   </blockquote>
   <h3 class="heading settled" data-level="3.3" id="poll-3-send-p3050r2-fix-c26-by-optimizing-linalgconjugated-for-noncomplex-value-types-to-library-working-group-for-c26"><span class="secno">3.3. </span><span class="content">Poll 3: Send "[P3050R2] Fix C++26 by optimizing linalg::conjugated for noncomplex value types" to Library Working Group for C++26.</span><a class="self-link" href="#poll-3-send-p3050r2-fix-c26-by-optimizing-linalgconjugated-for-noncomplex-value-types-to-library-working-group-for-c26"></a></h3>
   <blockquote>
    <p>This makes providing specialized algorithms for certain use cases easier and reduces the compilation time and template bloat.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>This simplifies both implementations of std::linalg (P1673R13, approved for C++26) and users' libraries that use components of std::linalg. It reduces the number of template instantiations needed to make common linear algebra code patterns work correctly and efficiently.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <h3 class="heading settled" data-level="3.4" id="poll-4-send-p3068r4-allowing-exception-throwing-in-constant-evaluation-to-library-working-group-for-c26"><span class="secno">3.4. </span><span class="content">Poll 4: Send "[P3068R4] Allowing exception throwing in constant-evaluation" to Library Working Group for C++26.</span><a class="self-link" href="#poll-4-send-p3068r4-allowing-exception-throwing-in-constant-evaluation-to-library-working-group-for-c26"></a></h3>
   <blockquote>
    <p>This is a significant step forward for constant evaluation in C++ and I expect to see the use of this functionality in papers in the very near future.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>This will make it possible to write code using static reflection (P2996 and follow-on proposals) in a way that looks as much like existing C++ code as possible. I particularly appreciate the paper’s examples, that make its effects on new code and impact on existing code clear.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>The "partial implementation" mentioned in the paper is something that worries me. However, I believe the errors can be still caught (if any) given that we have time for C++26 timeframe.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>I am concerned that using exceptions during constant evaluation will make code less maintainable, not more. We need usage experience with reflection before making language change of that nature.</p>
    <p>— Weakly Against</p>
   </blockquote>
   <h3 class="heading settled" data-level="3.5" id="poll-5-send-p3136r0-retiring-niebloids-to-library-working-group-for-c26"><span class="secno">3.5. </span><span class="content">Poll 5: Send "[P3136R0] Retiring niebloids" to Library Working Group for C++26.</span><a class="self-link" href="#poll-5-send-p3136r0-retiring-niebloids-to-library-working-group-for-c26"></a></h3>
   <blockquote>
    <p>This makes using these CPO as functions much more convenient and standard-compliant. As this reflects existing practice, such uses were already portable.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>We can call these things function objects now.  There’s no reason not to. In general, this helps make the meaning of the Standard more clear and its implementation strategy less ambiguous.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Hopefully, this will align the spec with what exists, and if we would like to modify by adding a language feature we can re-define/re-add the term.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>I would still rather not close out the possibility of adding core language features for implementing niebloids in future.</p>
    <p>— Weakly Against</p>
   </blockquote>
   <blockquote>
    <p>We should wait for a language solution.</p>
    <p>— Strongly Against</p>
   </blockquote>
   <h3 class="heading settled" data-level="3.6" id="poll-6-send-p3222r0-fix-c26-by-adding-transposed-special-cases-for-p2642-layouts-to-library-working-group-for-c26"><span class="secno">3.6. </span><span class="content">Poll 6: Send "[P3222R0] Fix C++26 by adding transposed special cases for P2642 layouts" to Library Working Group for C++26.</span><a class="self-link" href="#poll-6-send-p3222r0-fix-c26-by-adding-transposed-special-cases-for-p2642-layouts-to-library-working-group-for-c26"></a></h3>
   <blockquote>
    <p>This has the same motivation as P3050, just for the "transposed" function (that affects layouts) instead of the "conjugated" function (that affects accessors). Approving P32222 will simplify both implementations of std::linalg and users' libraries that use "transposed."</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Useful for my work.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>I was not part of the discussion, but quickly looking into the paper, not adding that now will lead to a breaking change. I trust authors here.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <h3 class="heading settled" data-level="3.7" id="poll-7-send-p3309r2-constexpr-atomic-and-atomic_ref-to-library-working-group-for-c26"><span class="secno">3.7. </span><span class="content">Poll 7: Send "[P3309R2] constexpr atomic and atomic_ref" to Library Working Group for C++26.</span><a class="self-link" href="#poll-7-send-p3309r2-constexpr-atomic-and-atomic_ref-to-library-working-group-for-c26"></a></h3>
   <blockquote>
    <p>Seems straightforward given we do not have multithreading during constant evaluation. This will unlock constexpr shared_ptr and many other data structures and algorithms that use atomic (without having to plaster if consteval into their implementation, although we’d still have to plaster constexpr).</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Given that we have an implementation experience, I don’t see a reason to hold this paper.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>This does not seem to be motivated.</p>
    <p>— Weakly Against</p>
   </blockquote>
   <h3 class="heading settled" data-level="3.8" id="poll-8-send-p3323r0-cv-qualified-types-in-atomic-and-atomic_ref-to-library-working-group-for-c26"><span class="secno">3.8. </span><span class="content">Poll 8: Send "[P3323R0] cv-qualified types in atomic and atomic_ref" to Library Working Group for C++26.</span><a class="self-link" href="#poll-8-send-p3323r0-cv-qualified-types-in-atomic-and-atomic_ref-to-library-working-group-for-c26"></a></h3>
   <blockquote>
    <p>A much-awaited good resolution to library defects and implementation divergence.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p><code class="highlight"><c- n>atomic_ref</c-></code> exists for use as a proxy reference type in an <code class="highlight"><c- n>mdspan</c-></code> accessor. That works already, but this proposal makes it work even better. For example, it makes <code class="highlight"><c- n>value_type</c-></code> consistent with its definition in <code class="highlight"><c- n>mdspan</c-></code> for const-qualified <code class="highlight"><c- n>element_type</c-></code>.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>
     Potential merge conflict between P3323R0/P3309R2 with respect to making sure that atomic_ref
     <volatile t> atomic operations are not considered constant expressions. Just needs to be brought to attention of LWG during wording review.</volatile>
    </p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>
     atomic
     <t>
      ::notify_* operations for  are non-const, while this paper does not add corresponding constraints to atomic_ref
      <t>
       ::notify operations.
There is inconsistency as volatile atomic
       <t>
         can always be constructed even if operations are not lock-free, and only invoking operations on it is ill-formed. This in particular allows is_lock_free to be checked on such an object.
In contrast, atomic_ref
        <t volatile> template itself is ill-formed.</t>
       </t>
      </t>
     </t>
    </p>
    <p>— Weakly Against</p>
   </blockquote>
   <h3 class="heading settled" data-level="3.9" id="poll-9-send-p3325r3-a-utility-for-creating-execution-environments-to-library-working-group-for-c26"><span class="secno">3.9. </span><span class="content">Poll 9: Send "[P3325R3] A Utility for Creating Execution Environments" to Library Working Group for C++26.</span><a class="self-link" href="#poll-9-send-p3325r3-a-utility-for-creating-execution-environments-to-library-working-group-for-c26"></a></h3>
   <blockquote>
    <p>Discussion in St. Louis made it clear why this utility needs to exist, and why it should be made available for users instead of being exposition-only or an implementation detail.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>We do need this functionality. Not often, but when we need it, it does need to be available in the standard.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>UX improvement for S/R.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>Given that we’re going to have execution environments, this seems like a reasonable quality of life improvement to make it easier to manipulate them. However, execution environments seem to be resulting in a lot of design headaches currently being mulled over among S&amp;R implementers and users.</p>
    <p>— Neutral</p>
   </blockquote>
   <h3 class="heading settled" data-level="3.10" id="poll-10-send-p0472r2-put-stdmonostate-in--to-library-working-group-for-c26"><span class="secno">3.10. </span><span class="content">Poll 10: Send "[P0472R2] Put std::monostate in <utility>" to Library Working Group for C++26.</utility></span><a class="self-link" href="#poll-10-send-p0472r2-put-stdmonostate-in--to-library-working-group-for-c26"></a></h3>
   <blockquote>
    <p>
     std::monostate is a fabulously useful class that shouldn’t require bringing in all of 
     <variant> to use.</variant>
    </p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Useful for user-defined variants, that want to also handle monostate, without bringing std::variant.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Let’s just do that if people see use cases.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>After 8 years, it doesn’t seem likely that developers will start using monostate for things other than variant. It is hard to believe that the header it was in kept them away.</p>
    <p>— Neutral</p>
   </blockquote>
   <blockquote>
    <utility>
      doesn’t stay cheap by taking in all the random one-off classes. 
     <p>— Neutral</p>
    </utility>
   </blockquote>
   <h3 class="heading settled" data-level="3.11" id="poll-11-send-p3355r1-fix-submdspan-for-c26-to-library-working-group-for-c26"><span class="secno">3.11. </span><span class="content">Poll 11: Send "[P3355R1] Fix submdspan for C++26" to Library Working Group for C++26.</span><a class="self-link" href="#poll-11-send-p3355r1-fix-submdspan-for-c26-to-library-working-group-for-c26"></a></h3>
   <blockquote>
    <p>This fixes a key use case of mdspan: iterating over compile-time-sized chunks of a run-time-sized array.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>The paper is very well-written and explains the rationale and technical bits with very high quality. It’s another good example of well-done homework.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <h3 class="heading settled" data-level="3.12" id="poll-12-send-p3369r0-constexpr-for-uninitialized_default_construct-to-library-working-group-for-c26"><span class="secno">3.12. </span><span class="content">Poll 12: Send "[P3369R0] constexpr for uninitialized_default_construct" to Library Working Group for C++26.</span><a class="self-link" href="#poll-12-send-p3369r0-constexpr-for-uninitialized_default_construct-to-library-working-group-for-c26"></a></h3>
   <blockquote>
    <p>With placement new being available at compile time, there is a tradeoff in making these algorithms available at compile-time.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>It doesn’t touch parallel algorithms (which is good), so no reason to hold it.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <h3 class="heading settled" data-level="3.13" id="poll-13-approve-p3399r0-adjusting-electronic-polls-to-a-hybrid-workflow-and-apply-the-change-to-the-process-of-library-evolution-working-group"><span class="secno">3.13. </span><span class="content">Poll 13: Approve "[P3399R0] Adjusting Electronic Polls to a Hybrid Workflow" and apply the change to the process of Library Evolution Working Group.</span><a class="self-link" href="#poll-13-approve-p3399r0-adjusting-electronic-polls-to-a-hybrid-workflow-and-apply-the-change-to-the-process-of-library-evolution-working-group"></a></h3>
   <blockquote>
    <p>People with design concerns who miss an LEWG live poll already have ways to be heard, both before and after the LEWG meeting where the live poll takes place. Electronic polls after the fact don’t increase their ability to communicate their concerns.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Electronic polling is helpful to gain additional feedback, and synchronize our async discussion. For face to face meetings it is less useful and would only cause unnecessary delays in a already slow process.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>It doesn’t make much sense to vote twice for the same paper if the voting audience is also the same. I hope that everyone who can’t participate to a given in-person vote but has opinion on a paper can express such opinions via email or similar, and that those concerns _are_ addressed before a vote is then expressed.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>I see how this allows us to move faster during the last meetings of the standard, however, it requires active participation in the week-long meeting, which may not be feasible. The pools in contrast, can be handled asynchronously.</p>
    <p>— Neutral</p>
   </blockquote>
   <blockquote>
    <p>I like the opportunity to participate in electronic polls. I like how they give the people who weren’t in the sessions the opportunity to cast their votes. I would hesitate to remove them from any of our processes, because I don’t find the rationale for doing that convincing.</p>
    <p>— Weakly Against</p>
   </blockquote>
   <blockquote>
    <p>(...) The data in the paper indicates that this will disenfranchise a substantial portion of the people that were previously voting in electronic polls. (...) In person discussions do a poor job of representing past reflector discussions.
(...) I am not receptive to the arguments that "the discussion is the valuable part of the process".  While I agree that the discussion is _more_ valuable than the voting, the voting still has substantial value.
(...) I am not receptive to the arguments that "EWG stopped polling a while back". While those statements are true, that doesn’t mean that those processes are better.  We don’t get better processes by always doing things the same way, or blindly following other’s processes.</p>
    <p>— Weakly Against</p>
   </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-p3467r0">[P3467R0]
   <dd>Inbal Levi, Fabio Fracassi, Ben Craig, Nevin Liber, Billy Baker, Corentin Jabot. <a href="https://wg21.link/p3467r0"><cite>2024-10 Library Evolution Polls</cite></a>. 16 October 2024. URL: <a href="https://wg21.link/p3467r0">https://wg21.link/p3467r0</a>
  </dl>