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  <title>P3214R0: 2024-04 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;
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	.head img[src*="logos/W3C"] {
		display: block;
		border: solid #1a5e9a;
		border: solid var(--logo-bg);
		border-width: .65rem .7rem .6rem;
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		background: #1a5e9a;
		background: var(--logo-bg);
		color: white;
		color: var(--logo-text);
		font-weight: bold;
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	.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);
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		#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>
<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 d765c696b, updated Fri Mar 8 15:58:52 2024 -0800" name="generator">
  <link href="https://wg21.link/P3214" 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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   <h1 class="p-name no-ref" id="title">P3214R0<br>2024-04 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="2024-05-22">2024-05-22</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_04_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-p2985r0-a-type-trait-for-detecting-virtual-base-classes-to-library-working-group-for-c26"><span class="secno">3.1</span> <span class="content">Poll 1: Send "[P2985R0] A type trait for detecting virtual base classes" to Library Working Group for C++26.</span></a>
      <li><a href="#poll-2-send-p2019r5-thread-attributes-to-library-working-group-for-c26"><span class="secno">3.2</span> <span class="content">Poll 2: Send "[P2019R5] Thread Attributes" to Library Working Group for C++26.</span></a>
      <li><a href="#poll-3-apply-changes-in-p2855r1-member-customization-points-for-senders-and-receivers-to-p2300-and-send-the-revised-paper-to-library-working-group-for-c26"><span class="secno">3.3</span> <span class="content">Poll 3: Apply changes in "[P2855R1] Member customization points for Senders and Receivers" to P2300, and send the revised paper to Library Working Group for C++26.</span></a>
      <li><a href="#poll-4-send-p3168r1-give-stdoptional-range-support-to-library-working-group-for-c26"><span class="secno">3.4</span> <span class="content">Poll 4: Send "[P3168R1] Give std::optional range support" to Library Working Group for C++26.</span></a>
      <li><a href="#poll-5-send-p2075r5-philox-as-an-extension-of-the-c-rng-engines-to-library-working-group-for-c26"><span class="secno">3.5</span> <span class="content">Poll 5: Send "[P2075R5] Philox as an extension of the C++ RNG engines" to Library Working Group for C++26.</span></a>
      <li><a href="#poll-6-send-p2927r2-observing-exceptions-stored-in-exception_ptr-to-library-working-group-for-c26"><span class="secno">3.6</span> <span class="content">Poll 6: Send "[P2927R2] Observing exceptions stored in exception_ptr" to Library Working Group for C++26.</span></a>
      <li><a href="#poll-7-send-p2997r1-removing-the-common-reference-requirement-from-the-indirectly-invocable-concepts-to-library-working-group-for-c26"><span class="secno">3.7</span> <span class="content">Poll 7: Send "[P2997R1] Removing the common reference requirement from the indirectly invocable concepts" to Library Working Group for C++26.</span></a>
      <li><a href="#poll-8-send-p2389r1-dextents-index-type-parameter-to-library-working-group-for-c26"><span class="secno">3.8</span> <span class="content">Poll 8: Send "[P2389R1] dextents Index Type Parameter" to Library Working Group for C++26.</span></a>
      <li><a href="#poll-9-apply-the-policy-suggested-in-p3201r1-lewg-nodiscard-policy-to-sd-9"><span class="secno">3.9</span> <span class="content">Poll 9: Apply the policy suggested in "[P3201R1] LEWG nodiscard policy" to SD-9.</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 2024-04, the C++ Library Evolution group conducted a series of electronic decision polls <a data-link-type="biblio" href="https://wg21.link/p3213r0" title="2024-04 Library Evolution Polls">[P3213R0]</a>.
This paper provides the results of those polls and summarizes the results.</p>
   <p>In total, 22 people participated in the polls.
Some participants opted to not vote on some polls.
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 "[P2985R0] A type trait for detecting virtual base classes" to Library Working Group for C++26. 
      <td>9 
      <td>8 
      <td>3 
      <td>0 
      <td>0 
      <td>Strong Consensus in favor 
     <tr>
      <td> Poll 2: Send "[P2019R5] Thread Attributes" to Library Working Group for C++26. 
      <td>9 
      <td>5 
      <td>2 
      <td>0 
      <td>4 
      <td>Weak consensus in favor 
     <tr>
      <td> Poll 3: Apply changes in "[P2855R1] Member customization points for Senders and Receivers" to P2300, and send the revised paper to Library Working Group for C++26. 
      <td>11 
      <td>2 
      <td>2 
      <td>0 
      <td>0 
      <td>Strong Consensus in favor 
     <tr>
      <td> Poll 4: Send "[P3168R1] Give std::optional range support" to Library Working Group for C++26. 
      <td>10 
      <td>3 
      <td>1 
      <td>2 
      <td>3 
      <td>Weak consensus in favor 
     <tr>
      <td> Poll 5: Send "[P2075R5] Philox as an extension of the C++ RNG engines" to Library Working Group for C++26. 
      <td>5 
      <td>7 
      <td>1 
      <td>2 
      <td>0 
      <td>Consensus in favor 
     <tr>
      <td> Poll 6: Send "[P2927R2] Observing exceptions stored in exception_ptr" to Library Working Group for C++26. 
      <td>9 
      <td>6 
      <td>2 
      <td>0 
      <td>2 
      <td>Consensus in favor 
     <tr>
      <td> Poll 7: Send "[P2997R1] Removing the common reference requirement from the indirectly invocable concepts" to Library Working Group for C++26. 
      <td>7 
      <td>6 
      <td>2 
      <td>0 
      <td>0 
      <td>Strong Consensus in favor 
     <tr>
      <td>
     <tr>
      <td> Poll 8: Send "[P2389R1] dextents Index Type Parameter" to Library Working Group for C++26. 
      <td>6 
      <td>5 
      <td>1 
      <td>2 
      <td>1 
      <td>Consensus in favor 
     <tr>
      <td> Poll 9: Apply the policy suggested in "[P3201R1] LEWG nodiscard policy" to SD-9. 
      <td>15 
      <td>3 
      <td>1 
      <td>1 
      <td>0 
      <td>Consensus in favor 
   </table>
   <p>All the polls have consensus in favor, and all but P3201R1 (which apply to SD-9) and P2855R1 (which appy to P2300) will be forwarded to LWG.</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-p2985r0-a-type-trait-for-detecting-virtual-base-classes-to-library-working-group-for-c26"><span class="secno">3.1. </span><span class="content">Poll 1: Send "[P2985R0] A type trait for detecting virtual base classes" to Library Working Group for C++26.</span><a class="self-link" href="#poll-1-send-p2985r0-a-type-trait-for-detecting-virtual-base-classes-to-library-working-group-for-c26"></a></h3>
   <blockquote>
    <p>With multiple instances of prior art and an "expert-only" implementation, it seems worth standardizing.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>I appreciate the paper’s extended and detailed discussion of use cases.  The move-converting constructor from a <code class="highlight"><c- n>weak_ptr</c-><c- o>&lt;</c-><c- n>Y</c-><c- o>></c-></code> to <code class="highlight"><c- n>weak_ptr</c-><c- o>&lt;</c-><c- n>T</c-><c- o>></c-></code> is particularly motivating.  Given that the conversion does not syntactically appear to involve observing the <code class="highlight"><c- n>shared_ptr</c-></code>, it might surprise many users for this to involve <code class="highlight"><c- n>lock</c-><c- p>()</c-></code>, with its possibly expensive thread synchronization.  This paper fixes that for common cases.  I also appreciate the paper’s careful discussion of the choice to behave differently than prior art, but in alignment with the core language definition of virtual base class.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>This trait is useful, and I agree with the author that we shouldn’t wait for "Reflection" to land, as this will only be one of many traits, all of we would need to re-consider.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>This is very niche and I don’t see much practical impact. However, this is a minor addition that fits well into the existing library.</p>
    <p>— Neutral</p>
   </blockquote>
   <h3 class="heading settled" data-level="3.2" id="poll-2-send-p2019r5-thread-attributes-to-library-working-group-for-c26"><span class="secno">3.2. </span><span class="content">Poll 2: Send "[P2019R5] Thread Attributes" to Library Working Group for C++26.</span><a class="self-link" href="#poll-2-send-p2019r5-thread-attributes-to-library-working-group-for-c26"></a></h3>
   <blockquote>
    <p>This might make it possible to actually use the standard library for creating threads.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Most users that create threads at least want the ability to name threads, as this helps debugging.  Many users also want to control threads' stack size.  It would be unfortunate if users found themselves unable to use <code class="highlight"><c- n>std</c-><c- o>::</c-><c- kr>thread</c-></code> or <code class="highlight"><c- n>std</c-><c- o>::</c-><c- n>jthread</c-></code> just because they couldn’t pass these common attributes to threads.
The paper surveys many existing operating systems for their ability to create or query threads with the proposed attributes.  The resulting design is a zero-overhead design, because it does not require storing attributes separately if the operating system’s thread does not have a query mechanism.  Using a named struct with named fields, as in an alternate proposal, would give users incorrect expectations about ABI stability.  This paper’s approach also makes adding new attribute types straightforward.
It would be excellent if there were a way to ask the operating system if an attribute were ignored or incorrect (e.g., if the string were too long), but that’s not a thing we can expect to be portable.  I understand that attributes are hints and that implementations can treat them as best-effort only.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>I think the paper proposes the best solution compared to other "Thread Attributes" proposal that I’ve seen.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>I like the functionality that this paper provides, and the design is relatively clean and usable.
The motivation for making the attributes non-movable to avoid copies/dangling-references seems weak. You can still construct a local variable of type thread::name_hint from a temporary std::string and then pass that local variable to a thread constructor and end up with a dangling reference.
I would also have liked to see explored a design based on the <code class="highlight"><c- n>queryable</c-></code> concept from P2300, but am not going to hold up the paper based on this.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>My preference would be to have a general, extensible facility for a bag-o-properties that can be used for thread attributes or p2300’s execution environments and sender attributes and many other places besides, but i won’t hold this feature up for that.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>I would have appreciated more interoperability: if one already has a threading API, they cannot use the newly introduced hints as there is no way to 1) identify that a given parameter is an hint, and 2) to extract the value of that parameter.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>An unnecessarily clever keyword-argument API is incoherent with the standard library and presents yet another obstacle for those considering C++ adoption.</p>
    <p>— Strongly Against</p>
   </blockquote>
   <blockquote>
    <p>Feels like a non C++ approach; we should have a single attributes class</p>
    <p>— Strongly Against</p>
   </blockquote>
   <h3 class="heading settled" data-level="3.3" id="poll-3-apply-changes-in-p2855r1-member-customization-points-for-senders-and-receivers-to-p2300-and-send-the-revised-paper-to-library-working-group-for-c26"><span class="secno">3.3. </span><span class="content">Poll 3: Apply changes in "[P2855R1] Member customization points for Senders and Receivers" to P2300, and send the revised paper to Library Working Group for C++26.</span><a class="self-link" href="#poll-3-apply-changes-in-p2855r1-member-customization-points-for-senders-and-receivers-to-p2300-and-send-the-revised-paper-to-library-working-group-for-c26"></a></h3>
   <blockquote>
    <p>tag_invoke was very clever but it’s impact on compile times not acceptable. This is a simple, sufficient solution until we can fix CPO in the language.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Member functions are much more readable and teachable than <code class="highlight"><c- n>tag_invoke</c-></code>. It’s not that <code class="highlight"><c- n>tag_invoke</c-></code> is bad, it’s that having an actual language feature for customization points would be a much better solution.
EWG is heavily occupied with other high-priority proposals aiming for C++26. Thus, it’s unlikely WG21 would have time to finish the proposed customization points language feature.  We also very much would like WG21 to approve P2300 for C++26.  Member functions are not hard to use and are not unreasonable for the P2300 use case, so I think it’s fine for P2300 to adopt the member functions approach.  Nevertheless, I still think EWG should pursue the language feature.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Although this is an improvement on the status quo, it’s regrettable that we are continuing the trend of adding opt-in concepts. Concepts should be duck typed.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <h3 class="heading settled" data-level="3.4" id="poll-4-send-p3168r1-give-stdoptional-range-support-to-library-working-group-for-c26"><span class="secno">3.4. </span><span class="content">Poll 4: Send "[P3168R1] Give std::optional range support" to Library Working Group for C++26.</span><a class="self-link" href="#poll-4-send-p3168r1-give-stdoptional-range-support-to-library-working-group-for-c26"></a></h3>
   <blockquote>
    <p>Although I still instinctively feel that this is somewhat unintuitive, I’ve found myself adequately convinced that it’s the most elegant way to address std::ranges pipelines that need to handle optionality. It also avoids us having to introduce the redundant views::maybe type.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>A range of 0 or 1 shows up very often in algorithm work, and the standard needs one. While a dedicated view might be useful and not add to the complexity of std::optional, this is a straightforward solution that is generally useful.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>This seems to be the conclusion of all the LEWG discussion around various proposals.  I agree that this direction minimizes "new things to learn."  I also agree that the iterator type should be implementation-defined rather than <code class="highlight"><c- n>T</c-><c- o>*</c-></code> or <code class="highlight"><c- n>T</c-><c- o>*</c-> <c- k>const</c-></code> (in fact, I would prefer that it be defined _not_ to be a pointer and that it not have public conversions to pointer, but I accept making the type implementation-defined).</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Provided this is actually necessary, it is a better solution than introducing a new word.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>It’s useful to be able to treat optional as a range, and this paper is strictly superior to the design it replaces (having a duplicate std::optional that is only usable as a range, mostly), but I wonder if simply having an adaptor is sufficient. Not opposed, just maybe not actively for.</p>
    <p>— Neutral</p>
   </blockquote>
   <blockquote>
    <p>This seems to add more and more tangential features to optional. I wasn’t in the discussion, but the minutes suggest a fair number of similar counter arguments (e.g. should _every_ object be a range-of-one?) with no discussion reflected in the minutes. I don’t understand the positive poll outcome from the minutes.</p>
    <p>— Weakly Against</p>
   </blockquote>
   <blockquote>
    <p>
     This is mixing concerns and will ultimately lead to ambiguities, all to save a few keystrokes (given an optional
     <range> both for(auto x : *opt) and for(auto x : opt) are valid syntaxes with different aspect.)
By the logic of this paper should any object be convertible to view::single?</range>
    </p>
    <p>— Strongly Against</p>
   </blockquote>
   <blockquote>
    <p>I feel like with this proposal we give a wrong impression of the std::optional semantics because std::optional is not a range and we should not pretend it is. With the given proposal we could ask ourselves why is not std::variant a range? It could potential return active element as well on the iterator dereference. Basically we might create a precedence where each type wrapper with special properties (like optional or variant or something else) would be considered as range, which to me is not a good idea.</p>
    <p>— Strongly Against</p>
   </blockquote>
   <h3 class="heading settled" data-level="3.5" id="poll-5-send-p2075r5-philox-as-an-extension-of-the-c-rng-engines-to-library-working-group-for-c26"><span class="secno">3.5. </span><span class="content">Poll 5: Send "[P2075R5] Philox as an extension of the C++ RNG engines" to Library Working Group for C++26.</span><a class="self-link" href="#poll-5-send-p2075r5-philox-as-an-extension-of-the-c-rng-engines-to-library-working-group-for-c26"></a></h3>
   <blockquote>
    <p>This proposal shows the strength of the C++ Standard Library’s random number generator design, in that it’s straightforward to add new generators.  The paper also highlights that the Philox engine has several implementations by hardware vendors.  The authors carefully explain and justify the features of <code class="highlight"><c- n>philox_engine</c-></code> that differ from the existing Standard engines.  In particular, I very much appreciate the presentation of alternative interfaces for <code class="highlight"><c- n>set_counter</c-></code>, and the explanation why <code class="highlight"><c- n>get_counter</c-></code> is not included.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>This random number engine is well-motivated and has extensive implementation experience. The state of the art for random number generation has advanced since we were standardizing the generators introduced in C++11.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Yes. And let’s get a trivial, lightweight RNG like PCG in there for the use-cases where the user doesn’t need such statistical-stringent generation and doesn’t want to rely on SIMD availability. More info (from https://github.com/colesbury/benchmark-rngs):
Time to get 100000000 philox randoms = 0.271853s
Time to get 100000000 philox_simd randoms = 0.117607s
Time to get 100000000 xoshiro256** randoms = 0.0561525s
Time to get 100000000 pcg64 randoms = 0.0990407s
Time to get 100000000 std::mt19937 randoms = 0.195286s</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Keeping up with the current state of RNGs was a promise C++ made, perhaps by accident. Making sure the standard library is useful is useful. I’m weakly in favor only because RNGs are not my domain.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>Been verified with ARM, AMD, NVIDIA, and Intel, and seems like a solid feature with field experience.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>This proposal needs more implementation and user experience. Moreover, none of the linked-to implementations match the specification. This is not standards-level quality.</p>
    <p>— Weakly Against</p>
   </blockquote>
   <h3 class="heading settled" data-level="3.6" id="poll-6-send-p2927r2-observing-exceptions-stored-in-exception_ptr-to-library-working-group-for-c26"><span class="secno">3.6. </span><span class="content">Poll 6: Send "[P2927R2] Observing exceptions stored in exception_ptr" to Library Working Group for C++26.</span><a class="self-link" href="#poll-6-send-p2927r2-observing-exceptions-stored-in-exception_ptr-to-library-working-group-for-c26"></a></h3>
   <blockquote>
    <p>Simplification after Kona 2023 was not discussed.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>I’ve wanted a facility like this a few times.  It always seemed silly to have an <code class="highlight"><c- n>exception_ptr</c-></code> -- the "exception equivalent of <code class="highlight"><c- n>any</c-></code>" -- in hand, and yet have to do a try-catch dance to get to the exception object.  This proposal fixes that.
The authors did a great job responding to LEWG feedback on how to make <code class="highlight"><c- n>exception_ptr_cast</c-></code> more usable (so users don’t have to worry about const qualification) while at the same time avoiding unimplementable cases.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>This paper solves an important problem, but I really wish we had followed the precedent set by any_cast and std::variant::get_if and required this function to take its parameter by pointer.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>exception_ptr_cast is the wrong name (too verbose). It should be exception_cast or try_cast.</p>
    <p>— Neutral</p>
   </blockquote>
   <h3 class="heading settled" data-level="3.7" id="poll-7-send-p2997r1-removing-the-common-reference-requirement-from-the-indirectly-invocable-concepts-to-library-working-group-for-c26"><span class="secno">3.7. </span><span class="content">Poll 7: Send "[P2997R1] Removing the common reference requirement from the indirectly invocable concepts" to Library Working Group for C++26.</span><a class="self-link" href="#poll-7-send-p2997r1-removing-the-common-reference-requirement-from-the-indirectly-invocable-concepts-to-library-working-group-for-c26"></a></h3>
   <blockquote>
    <p>Coroutines are leading to generators.  Generators lead to situations like the ones this paper fixes.  Even Python generators are single-pass, so it’s reasonable to give "ordinary" C++ users single-pass iterators that come from things like coroutines.  The authors make a strong argument that this would only affect usability (the requirements on users' callables) and not the algorithms themselves.
It’s enough motivation just to improve the error messages.  The GCC 13.2 message in Section 2’s first example would be difficult to understand or explain for most users.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>This fixes a clear bug in these concepts and is a textbook example of a situation where we should make an exception to our general guideline of not modifying concepts after standardization.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>I think the behavior that this paper proposes is correct because the issue that is described in the proposal looks really weird from the users standpoint.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>Solid arguments, I agree that we shouldn’t "propagate" the Feature test macro promoted.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>This appears to be a minor bugfix.</p>
    <p>— Neutral</p>
   </blockquote>
   <h3 class="heading settled" data-level="3.8" id="poll-8-send-p2389r1-dextents-index-type-parameter-to-library-working-group-for-c26"><span class="secno">3.8. </span><span class="content">Poll 8: Send "[P2389R1] dextents Index Type Parameter" to Library Working Group for C++26.</span><a class="self-link" href="#poll-8-send-p2389r1-dextents-index-type-parameter-to-library-working-group-for-c26"></a></h3>
   <blockquote>
    <p>Users sometimes need to name <code class="highlight"><c- n>mdspan</c-></code> types.  They can’t always rely on CTAD.  As a result, users need to name <code class="highlight"><c- n>extents</c-></code> specializations. <code class="highlight"><c- n>dextents</c-></code> was designed to make the common case of all dynamic extents easy and concise.  Later changes to <code class="highlight"><c- n>extents</c-></code> took away some of that conciseness.  This proposal brings back some of that.  It does so without breaking backwards compatibility, by introducing a new name <code class="highlight"><c- n>dims</c-></code>.
Given that <code class="highlight"><c- n>dims</c-></code> has an optional <code class="highlight"><c- n>IndexType</c-></code> template parameter, one could argue that <code class="highlight"><c- n>dextents</c-></code> is no longer needed and should be deprecated.  On the other hand, it’s harmless to keep around.  We could always deprecate it in a separate paper.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>The status quo of dextents was clearly broken; since we didn’t want to do a source-breaking change, we needed to introduce an alternative, and the specification for dims here is the right one.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Reducing the syntactic noise around declaring mdspan is beneficial.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>Abbreviation and clarity is good, but I would be wary in future of providing such things for the sole purpose of code reduction. Where possible, reducing the count of necessary items to memorize in the C++ library should take priority over code reduction for expert users. I also oppose _t-style traits for this reason.</p>
    <p>— Weakly Against</p>
   </blockquote>
   <blockquote>
    <p>The proposed name seems to potentially confuse "dimension" and "rank". I realize that "dims" should be read as "number of dimensions", so that "dims&lt;3>" means "has 3 <a class="property css" data-link-type="property">dimension</a> values", but this seem subtle and easy to confuse with "has 3 dimensions" or "is 3-dimensional". Something like "std::ndims" or "std::dyn_rank" would avoid such issues.</p>
    <p>— Strongly Against</p>
   </blockquote>
   <h3 class="heading settled" data-level="3.9" id="poll-9-apply-the-policy-suggested-in-p3201r1-lewg-nodiscard-policy-to-sd-9"><span class="secno">3.9. </span><span class="content">Poll 9: Apply the policy suggested in "[P3201R1] LEWG nodiscard policy" to SD-9.</span><a class="self-link" href="#poll-9-apply-the-policy-suggested-in-p3201r1-lewg-nodiscard-policy-to-sd-9"></a></h3>
   <blockquote>
    <p>I think this is the best possible outcome for nodiscard policy</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Implementers bring a lot more information and better judgement to bear on the question of whether any particular interface should be marked <span>[noexcept]</span> than LEWG does.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Spending time on providing hints to implementors that they neither desire or necessarily respect is a waste of precious committee time. The proliferation of <span>[nodiscard]</span> in library implementation indicates that implementors are doing the right thing without committee input or requirement.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>While I undertstand that LEWG doesn’t want to spend time in nodiscard discussions, users still look at the Standard as a source of inspiration, precedents, and good practices. Having a policy that we don’t use <span>[nodiscard]</span> in the Standard text may start raise questions about the usefulness of nodiscard itself.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>"Has a spurious impact" is still ungrammatical/unclear. But the policy is correct.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Make less work for us. Yay!</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>I don’t understand how this is better than Wakely’s previous paper which at least attempts to provide categories for where we should use <span>[nodiscard]</span>, but it’s clearly better than attempting to enumerate those places like some alternate papers, and if this gets us to stop talking about it all the time - then sure.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>While I like the intent of making it completely QoI I do think a recommendation of what should be reasonably marked no discard in some official document (could be SD-9, the standard, etc) would help ensuring the quality of implementations is aligned with the expectations of their users.</p>
    <p>— Weakly Against</p>
   </blockquote>
   <p>Editor’s note: The policy contains a link to the paper, which contains the information on suggested locations where <code class="highlight"><c- p>[[</c-><c- n>nodiscard</c-><c- p>]]</c-></code> should appear, so the information remains avaliable (even if not as part of the policy itself).</p>
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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-p3213r0">[P3213R0]
   <dd>Inbal Levi; et al. <a href="https://wg21.link/p3213r0"><cite>2024-04 Library Evolution Polls</cite></a>. 15 May 2024. URL: <a href="https://wg21.link/p3213r0">https://wg21.link/p3213r0</a>
  </dl>