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  <title>P2451R0: 2021 September 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;
		}
		#toc .content:hover,
		#toc .content:focus {
			background: rgba(75%, 75%, 75%, .25);
			background: var(--a-hover-bg);
			border-bottom: 3px solid #054572;
			border-bottom: 3px solid var(--toclink-underline);
			margin-bottom: -3px;
		}
		#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 span:not(.dfn-paneled) {
			white-space: nowrap;
			color: transparent; }
		ul.index li a:hover + span,
		ul.index li a:focus + span {
			color: #707070;
			color: var(--indexinfo-text);
		}
	}

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

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

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

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

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

/** Outdated warning **********************************************************/

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outdated-spec {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

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outdated-warning {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	background: var(--outdated-bg);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	color: var(--outdated-text);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	box-shadow: 0 0 1em var(--outdated-shadow);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

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outdated-warning a {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

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

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outdated-warning button {
	color: var(--outdated-text);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	box-shadow: 0 0 1em var(--outdated-shadow);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

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outdated-warning a {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

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

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outdated-warning button {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

.outdated-warning span {
	display: block;
}

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

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

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

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

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



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

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

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

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

	@media not print {
		.overlarge {
			overflow-x: auto;
			/* See Lea Verou's explanation background-attachment:
			* http://lea.verou.me/2012/04/background-attachment-local/
			*
			background: top left  / 4em 100% linear-gradient(to right,  #ffffff, rgba(255, 255, 255, 0)) local,
						top right / 4em 100% linear-gradient(to left, #ffffff, rgba(255, 255, 255, 0)) local,
						top left  / 1em 100% linear-gradient(to right,  #c3c3c5, rgba(195, 195, 197, 0)) scroll,
						top right / 1em 100% linear-gradient(to left, #c3c3c5, rgba(195, 195, 197, 0)) scroll,
						white;
			background-repeat: no-repeat;
			*/
		}
	}
</style>
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      padding: 0px 10px;
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    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 */
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    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 */
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    blockquote c-[py] { color: inherit; } /* Name.Property */
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    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 a210b7d86, updated Thu Sep 16 13:45:19 2021 -0700" name="generator">
  <link href="https://wg21.link/P2451" rel="canonical">
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table, th, tr, td {
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  <div class="head">
   <p data-fill-with="logo"></p>
   <h1 class="p-name no-ref" id="title">P2451R0<br>2021 September 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="2021-09-28">2021-09-28</time></span></h2>
   <div data-fill-with="spec-metadata">
    <dl>
     <dt class="editor">Author:
     <dd class="editor p-author h-card vcard"><a class="p-name fn u-email email" href="mailto:brycelelbach@gmail.com">Bryce Adelstein Lelbach (he/him/his) — Library Evolution Chair</a> (<span class="p-org org">NVIDIA</span>)
     <dt>Source:
     <dd><a href="https://github.com/brycelelbach/wg21_p2451_2021_september_library_evolution_poll_outcomes/blob/main/2021_september_library_evolution_poll_outcomes.bs">GitHub</a>
     <dt>Issue Tracking:
     <dd><a href="https://github.com/brycelelbach/wg21_p2451_2021_september_library_evolution_poll_outcomes/issues">GitHub</a>
     <dt>Project:
     <dd>ISO/IEC JTC1/SC22/WG21 14882: Programming Language — C++
     <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="#selected-poll-comments"><span class="secno">3</span> <span class="content">Selected Poll Comments</span></a>
     <ol class="toc">
      <li><a href="#poll-1"><span class="secno">3.1</span> <span class="content">Poll 1: <span>[P2418R0]</span> Add Support For <code class="highlight"><c- n>std</c-><c- o>::</c-><c- n>generator</c-></code>-like Types To <code class="highlight"><c- n>std</c-><c- o>::</c-><c- n>format</c-></code></span></a>
      <li><a href="#poll-2"><span class="secno">3.2</span> <span class="content">Poll 2: <span>[P2415R1]</span> What Is A <code class="highlight"><c- n>view</c-></code>?</span></a>
      <li><a href="#poll-3"><span class="secno">3.3</span> <span class="content">Poll 3: <span>[P2432R0]</span> Fix <code class="highlight"><c- n>istream_view</c-></code></span></a>
      <li><a href="#poll-4"><span class="secno">3.4</span> <span class="content">Poll 4: <span>[P2351R0]</span> Mark All Library Static Cast Wrappers As <code class="highlight"><c- p>[[</c-><c- n>nodiscard</c-><c- p>]]</c-></code></span></a>
      <li><a href="#poll-5"><span class="secno">3.5</span> <span class="content">Poll 5: <span>[P2291R2]</span> Add <code class="highlight"><c- k>constexpr</c-></code> Modifiers To Functions <code class="highlight"><c- n>to_chars</c-></code> And <code class="highlight"><c- n>from_chars</c-></code> For Integral Types In <code class="highlight"><c- o>&lt;</c-><c- n>charconv</c-><c- o>></c-></code> Header</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 September 2021, the C++ Library Evolution group conducted a series of
  electronic decision polls <a data-link-type="biblio" href="#biblio-p2436r0">[P2436R0]</a>.
This paper provides the results of those polls and summarizes the results.</p>
   <p>In total, 23 people participated in the polls.
Some participants opted to not vote on some polls.
Thank you to everyone who participated, and to the proposal 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 style="padding-bottom: 10px;">Poll 
      <th>SF 
      <th>WF 
      <th>N 
      <th>WA 
      <th>SA 
      <th>Outcome 
     <tr>
      <td style="padding-bottom: 16px;"> Poll 1: Send <a data-link-type="biblio" href="#biblio-p2418r0">[P2418R0]</a> (Add Support For <code class="highlight"><c- n>std</c-><c- o>::</c-><c- n>generator</c-></code>-like Types To <code class="highlight"><c- n>std</c-><c- o>::</c-><c- n>format</c-></code>) to Library Working Group for C++23, classified as an improvement
  of an existing feature (<a data-link-type="biblio" href="#biblio-p0592r4">[P0592R4]</a> bucket 2 item), with the recommendation
  that implementations retroactively apply it to C++20. 
      <td>12 
      <td>7 
      <td>0 
      <td>1 
      <td>0 
      <td>Consenus in favor. 
     <tr>
      <td style="padding-bottom: 16px;"> Poll 2: Send <a data-link-type="biblio" href="#biblio-p2415r1">[P2415R1]</a> (What Is A <code class="highlight"><c- n>view</c-></code>?) to Library Working Group for
  C++23, classified as an improvement of an existing feature (<a data-link-type="biblio" href="#biblio-p0592r4">[P0592R4]</a> bucket
  2 item), with the recommendation that implementations retroactively apply it
  to C++20. 
      <td>7 
      <td>6 
      <td>1 
      <td>1 
      <td>3 
      <td>Consensus in favor. 
     <tr>
      <td style="padding-bottom: 16px;"> Poll 3: Send <a data-link-type="biblio" href="#biblio-p2432r0">[P2432R0]</a> (Fix <code class="highlight"><c- n>istream_view</c-></code>) to Library Working Group for
  C++23, classified as an improvement of an existing feature (<a data-link-type="biblio" href="#biblio-p0592r4">[P0592R4]</a> bucket
  2 item), with the recommendation that implementations retroactively apply it to
  C++20. 
      <td>6 
      <td>8 
      <td>4 
      <td>3 
      <td>1 
      <td>Weak consensus in favor. 
     <tr>
      <td style="padding-bottom: 16px;"> Poll 4: Send <a data-link-type="biblio" href="#biblio-p2351r0">[P2351R0]</a> (Mark All Library Static Cast Wrappers As <code class="highlight"><c- p>[[</c-><c- n>nodiscard</c-><c- p>]]</c-></code>) to Library Working Group for C++23, classified as an
  improvement of an existing feature (<a data-link-type="biblio" href="#biblio-p0592r4">[P0592R4]</a> bucket 2 item). 
      <td>7 
      <td>9 
      <td>4 
      <td>2 
      <td>2 
      <td>Weak consensus in favor. 
     <tr>
      <td style="padding-bottom: 16px;"> Poll 5: Send <a data-link-type="biblio" href="#biblio-p2291r2">[P2291R2]</a> (Add <code class="highlight"><c- k>constexpr</c-></code> Modifiers To Functions <code class="highlight"><c- n>to_chars</c-></code> And <code class="highlight"><c- n>from_chars</c-></code> For Integral Types In <code class="highlight"><c- o>&lt;</c-><c- n>charconv</c-><c- o>></c-></code> Header) to Library Working
  Group for C++23, classified as an improvement of an existing feature
  (<a data-link-type="biblio" href="#biblio-p0592r4">[P0592R4]</a> bucket 2 item). 
      <td>13 
      <td>7 
      <td>1 
      <td>0 
      <td>0 
      <td>Strong consensus in favor. 
   </table>
   <h2 class="heading settled" data-level="3" id="selected-poll-comments"><span class="secno">3. </span><span class="content">Selected Poll Comments</span><a class="self-link" href="#selected-poll-comments"></a></h2>
   <h3 class="heading settled" data-level="3.1" id="poll-1"><span class="secno">3.1. </span><span class="content">Poll 1: <a data-link-type="biblio" href="#biblio-p2418r0">[P2418R0]</a> Add Support For <code class="highlight"><c- n>std</c-><c- o>::</c-><c- n>generator</c-></code>-like Types To <code class="highlight"><c- n>std</c-><c- o>::</c-><c- n>format</c-></code></span><a class="self-link" href="#poll-1"></a></h3>
   <blockquote>
    <p>This fixes cooperation between major C++20 features (ranges and format). Without out, some ranges will be inherently not printable.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Without this change it will be impossible to format <code class="highlight"><c- n>std</c-><c- o>::</c-><c- n>generator</c-></code> and other types that are neither const-iterable nor copyable.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>An improvement, but yet another one that is not really suitable for a DR at this stage.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>I’ll all for fixes to C++20 (and I think this is one). In my mind, C++20 isn’t set in stone until C++23 is close to release.</p>
    <p>Also, I am quite fine to throw bitfields under the bus. Always.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>I support the general direction of the paper, but I think it’s too late for us to continue retroactively changing C++20. I would prefer we instead make a breaking change in C++23. We need to have clear deadlines and releases, but we shouldn’t be afraid to fix our mistakes. The more changes we make to C++20, the slower C++20 adoption will be.</p>
    <p>— Weakly Against</p>
   </blockquote>
   <h3 class="heading settled" data-level="3.2" id="poll-2"><span class="secno">3.2. </span><span class="content">Poll 2: <a data-link-type="biblio" href="#biblio-p2415r1">[P2415R1]</a> What Is A <code class="highlight"><c- n>view</c-></code>?</span><a class="self-link" href="#poll-2"></a></h3>
   <blockquote>
    <p>The view concept has seen so many changes since its initial proposal that its meaning has become muddled. This paper brings some much-needed clarity and is also a significant usability improvement.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>I see the essential feature of a view as "a thing that refers to another thing," rather than its asymptotic complexity. The <code class="highlight"><c- n>shared_ptr</c-></code> example of LWG3452 is compelling. Making a thing A refer to another thing B would best happen at A’s construction, so it makes sense to me to change the wording to focus on construction, rather than destruction. <code class="highlight"><c- n>owning_view</c-></code> sounds a bit funny ("owning" and "view" feel like opposites), but it does neatly solve the problem of dangling rvalue non-view ranges.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>The O(1) requirement in views is problematic, this is a step in the right direction</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>The ranges library is in general overconstrained, requiring that user-supplied types be "well-behaved" in a complete, abstract sense rather than that they actually behave in use. Performance requirements in particular are questionable, since the library cannot act in reliance on them other than via a multiplicative factor.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>I am definitely in favor of the change to the complexity requirements. I don’t fully understand the other changes or the ramifications of them.</p>
    <p>— Neutral</p>
   </blockquote>
   <blockquote>
    <p>This change would do serious and lasting damage to the design of <code class="highlight"><c- n>std</c-><c- o>::</c-><c- n>ranges</c-></code>, further muddying the distinction between view and ranges, and opening subtle new opportunities for dangling references. No, no, no.</p>
    <p>— Strongly Against</p>
   </blockquote>
   <blockquote>
    <p>I really believe that rvalue/lvalue difference for meaning of <code class="highlight"><c- nl>views</c-><c- p>:</c-><c- n>all</c-></code> is too subtle, and we will pay for it in year. And I found it unfortunate that this change is bundled, with very useful and welcomed clarification on meaning of view.</p>
    <p>— Strongly Against</p>
   </blockquote>
   <blockquote>
    <p>There are subtleties here that I don’t understand and make me uncomfortable participating.</p>
    <p>— Did Not Participate</p>
   </blockquote>
   <blockquote>
    <p>I want to participate in this poll, but I don’t think I have the time/knowledge/experience with ranges to do so.</p>
    <p>I think it probably makes sense, but I’m not sure of all the ramifications. I would probably go with whatever Eric and Casey say. If the people with experience (ie the paper authors and the ranges authors) all agree with it than great (but I haven’t followed enough to even know their opinions).</p>
    <p>— Did Not Participate</p>
   </blockquote>
   <h3 class="heading settled" data-level="3.3" id="poll-3"><span class="secno">3.3. </span><span class="content">Poll 3: <a data-link-type="biblio" href="#biblio-p2432r0">[P2432R0]</a> Fix <code class="highlight"><c- n>istream_view</c-></code></span><a class="self-link" href="#poll-3"></a></h3>
   <blockquote>
    <p>This is an annoying and preventable inconsistency, and we should use the chance to fix this while we still can.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>It’s unfortunate to do that post-fact, and it should have been fixed years ago, but better have some (controlled) pain now as opposed to ongoing pain over the next decade or so.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>I really strongly encourage consistency. This problem will not impact large amount of users, and by the same reasoning, change that late is not breaking a lot of code.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>I’m all for fixing C++20 now, before it gets used by lots an lots of people. Adoption is always slow, we can continue to fix things.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>SF for adding <code class="highlight"><c- n>views</c-><c- o>::</c-><c- n>istream</c-></code>. WA on changing <code class="highlight"><c- n>istream_view</c-></code> (once we have <code class="highlight"><c- n>views</c-><c- o>::</c-><c- n>istream</c-></code>, nobody should be using <code class="highlight"><c- n>istream_view</c-></code>; it seems unnecessarily breaking all things considered). WF overall.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>Consistency by itself is a poor reason to change something in C++20, but given that there are numerous other retroactive changes being made, this change is a reasonable candidate for that set.</p>
    <p>— Neutral</p>
   </blockquote>
   <blockquote>
    <p>Consistency in the standard library would be nice, but [my users] don’t care about binary compatibility and will use whatever API is available at the time we need the feature.</p>
    <p>— Neutral</p>
   </blockquote>
   <blockquote>
    <p>These are not things that need to be applied as a DR. We add functions to classes regularly. We add concepts. We even subtly change the results of things like "begin".</p>
    <p>In addition, this proposal needs more bake time, particularly since it has substantial chance of breaking things.</p>
    <p>— Weakly Against</p>
   </blockquote>
   <blockquote>
    <p>Changed from Weakly Favor [at the telecon] to Strongly against here. I think the best option is for us to deprecate <code class="highlight"><c- n>std</c-><c- o>::</c-><c- n>ranges</c-><c- o>::</c-><c- n>istream_view</c-></code> and add <code class="highlight"><c- n>std</c-><c- o>::</c-><c- n>views</c-><c- o>::</c-><c- n>istream</c-></code> in its place.</p>
    <p>— Strongly Against</p>
   </blockquote>
   <h3 class="heading settled" data-level="3.4" id="poll-4"><span class="secno">3.4. </span><span class="content">Poll 4: <a data-link-type="biblio" href="#biblio-p2351r0">[P2351R0]</a> Mark All Library Static Cast Wrappers As <code class="highlight"><c- p>[[</c-><c- n>nodiscard</c-><c- p>]]</c-></code></span><a class="self-link" href="#poll-4"></a></h3>
   <blockquote>
    <p>I encourage explicit <code class="highlight"><c- p>[[</c-><c- n>nodiscard</c-><c- p>]]</c-></code> markings in the standard -- they help catch real world bugs!</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>This matches existing practice and make the intent of these function clearer. It has a very low burden on the standard and implementers.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Although [I] would prefer <code class="highlight"><c- p>[[</c-><c- n>nodiscard</c-><c- p>]]</c-></code> be applied liberally to the standard library, [I] would also be satisfied with it as [Quality of Implementation (QoI)].</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>While the direct value of including attributes with no reliable, normative effect in the standard is questionable, there is a very real indirect effect: if implementations can expect that other implementations will issue warnings for the same code, they are less likely to withhold the warnings for compatibility reasons.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>I find the whole idea of <code class="highlight"><c- p>[[</c-><c- n>nodiscard</c-><c- p>]]</c-></code> backwards. The compiler should warn by default on discarded return values. I should have to do something special to get it to stop emitting a warning. If the compiler is doing its job, then nothing should need <code class="highlight"><c- p>[[</c-><c- n>nodiscard</c-><c- p>]]</c-></code> decoration. On the other hand, I wouldn’t mind if the standard library did this.</p>
    <p>— Neutral</p>
   </blockquote>
   <blockquote>
    <p>I am generally in favour of tightening the requirements of [Quality of Implementation (QoI)] to standardize high quality implementations. However In this case I think we can get the result with out prescribing all details.</p>
    <p>— Neutral</p>
   </blockquote>
   <blockquote>
    <p>I think blanket wording saying which functions should be treated as nodiscard would be superior to explicitly adding it to individual declarations.</p>
    <p>— Weakly Against</p>
   </blockquote>
   <blockquote>
    <p>It seems a waste of valuable LWG time to forward <code class="highlight"><c- p>[[</c-><c- n>nodiscard</c-><c- p>]]</c-></code> papers without first having reached agreement on whether we want such annotations in the standard at all. I also have serious reservations about the process employed where the mailing list discussion was supposedly tabled until the end of the year, then a month later the paper is suddenly submitted to electronic polling.</p>
    <p>— Strongly Against</p>
   </blockquote>
   <blockquote>
    <ul>
     <li data-md>
      <p>Has no normative effect.</p>
     <li data-md>
      <p>Poor use of LEWG time (and it won’t stop with just this <code class="highlight"><c- p>[[</c-><c- n>nodiscard</c-><c- p>]]</c-></code> paper).</p>
     <li data-md>
      <p>Poor use of WG21 time.</p>
     <li data-md>
      <p>There are many (if not all) bucket 3 items I would much rather have before this.</p>
     <li data-md>
      <p>No general rules for applying <code class="highlight"><c- p>[[</c-><c- n>nodiscard</c-><c- p>]]</c-></code>.</p>
     <li data-md>
      <p>Moves the standard towards being prescriptive, not descriptive.</p>
     <li data-md>
      <p>Much better to have a standing document of these things instead of littering the standard with them.</p>
     <li data-md>
      <p>Controversial papers should not skip LEWG telecons and go straight to electronic polling.</p>
     <li data-md>
      <p>This is something implementors should be doing instead of spending valuable committee time legislating it.</p>
    </ul>
    <p>— Strongly Against</p>
   </blockquote>
   <h3 class="heading settled" data-level="3.5" id="poll-5"><span class="secno">3.5. </span><span class="content">Poll 5: <a data-link-type="biblio" href="#biblio-p2291r2">[P2291R2]</a> Add <code class="highlight"><c- k>constexpr</c-></code> Modifiers To Functions <code class="highlight"><c- n>to_chars</c-></code> And <code class="highlight"><c- n>from_chars</c-></code> For Integral Types In <code class="highlight"><c- o>&lt;</c-><c- n>charconv</c-><c- o>></c-></code> Header</span><a class="self-link" href="#poll-5"></a></h3>
   <blockquote>
    <p>Having finally specified these most basic operations in a way that is appropriate for the language, it only makes sense that they would be made available for compile time programming. The lack of floating-point support is an obviously necessary concession to practicality which can hopefully be eventually addressed.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>According to implementers this is not hard to provide and would allow constexpr format in the future, which is an useful feature to have. It would certainly help some constexpr libraries like CTRE, etc.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>This is a step in the right direction, we should make functionality available in constexpr context unless there is a good reason not to.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>This seems straightforward, and it has been tested, and it’s the kind of thing you would expect to be able to do at compile time.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>I know that this change will be a welcome one for implementers of libraries like CTRE. However, I’m concerned that this will require implementation heroics to prevent large compile time costs for all files that only include <code class="highlight"><c- o>&lt;</c-><c- n>charconv</c-><c- o>></c-></code> for use at runtime. Although there are obvious approaches that could be used to mitigate this, the paper doesn’t discuss the additional compile time overhead of moving integral <code class="highlight"><c- n>to_chars</c-></code>/<code class="highlight"><c- n>from_chars</c-></code> into the header nor possible mitigations.</p>
    <p>— Neutral</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-p0592r4">[P0592R4]
   <dd>Ville Voutilainen. <a href="https://wg21.link/p0592r4"><cite>To boldly suggest an overall plan for C++23</cite></a>. 25 November 2019. URL: <a href="https://wg21.link/p0592r4">https://wg21.link/p0592r4</a>
   <dt id="biblio-p2291r2">[P2291R2]
   <dd>Daniil Goncharov, Karaev Alexander. <a href="https://wg21.link/p2291r2"><cite>Add Constexpr Modifiers to Functions to_chars and from_chars for Integral Types in Header</cite></a>. 17 August 2021. URL: <a href="https://wg21.link/p2291r2">https://wg21.link/p2291r2</a>
   <dt id="biblio-p2351r0">[P2351R0]
   <dd>Hana Dusíková. <a href="https://wg21.link/p2351r0"><cite>Mark all library static cast wrappers as [[nodiscard]]</cite></a>. 25 April 2021. URL: <a href="https://wg21.link/p2351r0">https://wg21.link/p2351r0</a>
   <dt id="biblio-p2415r1">[P2415R1]
   <dd>Barry Revzin, Tim Song. <a href="https://wg21.link/p2415r1"><cite>What is a view?</cite></a>. 16 August 2021. URL: <a href="https://wg21.link/p2415r1">https://wg21.link/p2415r1</a>
   <dt id="biblio-p2418r0">[P2418R0]
   <dd>Victor Zverovich. <a href="https://wg21.link/p2418r0"><cite>Add support for std::generator-like types to std::format</cite></a>. 8 August 2021. URL: <a href="https://wg21.link/p2418r0">https://wg21.link/p2418r0</a>
   <dt id="biblio-p2432r0">[P2432R0]
   <dd>Nicolai Josuttis. <a href="https://wg21.link/p2432r0"><cite>Fixing istream_view</cite></a>. 27 August 2021. URL: <a href="https://wg21.link/p2432r0">https://wg21.link/p2432r0</a>
   <dt id="biblio-p2436r0">[P2436R0]
   <dd>Bryce Adelstein Lelbach. <a href="https://wg21.link/p2436r0"><cite>2021 September Library Evolution Polls</cite></a>. 14 September 2021. URL: <a href="https://wg21.link/p2436r0">https://wg21.link/p2436r0</a>
  </dl>