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  <title>P2333R0: 2021 Winter 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,
	#subtitle {
		/* #subtitle 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: none;
		border-bottom: 1px solid #707070;
		border-bottom: 1px solid var(--a-normal-underline);
		/* Need a bit of extending for it to look okay */
		padding: 0 1px 0;
		margin: 0 -1px 0;
	}
	a:visited {
		color: #034575;
		color: var(--a-visited-text);
		border-bottom-color: #bbb;
		border-bottom-color: var(--a-visited-underline);
	}

	/* Use distinguishing colors when user is interacting with the link */
	a[href]:focus,
	a[href]:hover {
		background: #f8f8f8;
		background: rgba(75%, 75%, 75%, .25);
		background: var(--a-hover-bg);
		border-bottom-width: 3px;
		margin-bottom: -2px;
	}
	a[href]:active {
		color: #c00;
		color: var(--a-active-text);
		border-color: #c00;
		border-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-top: 0.1rem;
		/* Larger, more consistently-sized click target */
		display: block;
		/* 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: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; }
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    blockquote code.highlight:not(.idl) { padding: initial; }
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    blockquote c-[kc] { color: inherit; } /* Keyword.Constant */
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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 b94c7e755, updated Fri Feb 19 16:28:59 2021 -0800" name="generator">
  <link href="https://wg21.link/P2333R0" rel="canonical">
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<style>
pre {
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}
.ins, ins, ins *, span.ins, span.ins * {
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  <div class="head">
   <p data-fill-with="logo"></p>
   <h1 class="p-name no-ref" id="title">P2333R0<br>2021 Winter Library Evolution Poll Outcomes</h1>
   <h2 class="no-num no-toc no-ref heading settled" id="subtitle"><span class="content">Published Proposal, <time class="dt-updated" datetime="2021-03-12">2021-03-12</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_p2333_2021_fall_library_evolution_poll_outcomes/blob/main/2021_fall_library_evolution_poll_outcomes.bs">GitHub</a>
     <dt>Issue Tracking:
     <dd><a href="https://github.com/brycelelbach/wg21_p2233_2021_fall_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="#summarized-poll-results"><span class="secno">2</span> <span class="content">Summarized Poll Results</span></a>
    <li>
     <a href="#detailed-results"><span class="secno">3</span> <span class="content">Selected Comments</span></a>
     <ol class="toc">
      <li><a href="#poll-1"><span class="secno">3.1</span> <span class="content">Poll 1: <span>[P0288R7]</span> The Feature Formerly Known As <code class="highlight"><c- n>any_invocable</c-></code></span></a>
      <li><a href="#poll-2"><span class="secno">3.2</span> <span class="content">Poll 2: <span>[P1642R5]</span> Freestanding [utilities], [ranges], And [iterators]</span></a>
      <li><a href="#poll-3"><span class="secno">3.3</span> <span class="content">Poll 3: <span>[P2216R2]</span> <code class="highlight"><c- n>std</c-><c- o>::</c-><c- n>format</c-></code> Improvements</span></a>
      <li><a href="#poll-4"><span class="secno">3.4</span> <span class="content">Poll 4: <span>[P2077R2]</span> Heterogeneous Erasure Overloads For Associative Containers</span></a>
      <li><a href="#poll-5"><span class="secno">3.5</span> <span class="content">Poll 5: <span>[P2136R2]</span> <code class="highlight"><c- n>invoke_r</c-></code></span></a>
      <li><a href="#poll-6"><span class="secno">3.6</span> <span class="content">Poll 6: <span>[P1951R0]</span> Default Arguments For <code class="highlight"><c- n>pair</c-></code>'s Forwarding Constructor</span></a>
      <li><a href="#poll-7"><span class="secno">3.7</span> <span class="content">Poll 7: <span>[P2231R0]</span> Missing <code class="highlight"><c- k>constexpr</c-></code> In <code class="highlight"><c- n>optional</c-></code> And <code class="highlight"><c- n>variant</c-></code></span></a>
      <li><a href="#poll-8"><span class="secno">3.8</span> <span class="content">Poll 8: <span>[P0901R8]</span> Size Feedback In <code class="highlight"><c- k>operator</c-> <c- k>new</c-></code></span></a>
      <li><a href="#poll-9"><span class="secno">3.9</span> <span class="content">Poll 9: <span>[P1478R6]</span> Byte-wise Atomic <code class="highlight"><c- n>memcpy</c-></code></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 Winter 2021, the C++ Library Evolution group conducted a series of electronic
  decision polls <a data-link-type="biblio" href="#biblio-p2289r0">[P2289R0]</a>.
This paper provides the results of those polls and summarizes the results.</p>
   <p>In total, 31 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="summarized-poll-results"><span class="secno">2. </span><span class="content">Summarized Poll Results</span><a class="self-link" href="#summarized-poll-results"></a></h2>
   <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: Modify <a data-link-type="biblio" href="#biblio-p0288r7">[P0288R7]</a> (<code class="highlight"><c- n>any_invocable</c-></code>) by renaming <code class="highlight"><c- n>any_invocable</c-></code> to <code class="highlight"><c- n>move_only_function</c-></code> (as per <a data-link-type="biblio" href="#biblio-p2265r0">[P2265R0]</a> Renaming <code class="highlight"><c- n>any_invocable</c-></code>) and
  placing the facility in <code class="highlight"><c- o>&lt;</c-><c- n>functional</c-><c- o>></c-></code> instead of adding a new header, and
  then send the revised paper to LWG for C++23, classified as an addition
  (<a data-link-type="biblio" href="#biblio-p0592r4">[P0592R4]</a> bucket 3 item). 
      <td>9 
      <td>13 
      <td>4 
      <td>1 
      <td>2 
      <td>Consensus in favor. 
     <tr>
      <td style="padding-bottom: 16px;"> Poll 2: Send <a data-link-type="biblio" href="#biblio-p1642r5">[P1642R5]</a> (Freestanding [utilities], [ranges], And [iterators])
  to LWG, classified as an improvement of an existing feature (<a data-link-type="biblio" href="#biblio-p0592r4">[P0592R4]</a> bucket 2 item). 
      <td>13 
      <td>13 
      <td>0 
      <td>0 
      <td>0 
      <td>Unanimous consensus in favor. 
     <tr>
      <td style="padding-bottom: 16px;"> Poll 3: Send <a data-link-type="biblio" href="#biblio-p2216r2">[P2216R2]</a> (<code class="highlight"><c- n>std</c-><c- o>::</c-><c- n>format</c-></code> Improvements) to LWG 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>15 
      <td>11 
      <td>1 
      <td>0 
      <td>0 
      <td>Strong consensus in favor. 
     <tr>
      <td style="padding-bottom: 16px;"> Poll 4: Send <a data-link-type="biblio" href="#biblio-p2077r2">[P2077R2]</a> (Heterogeneous Erasure Overloads For Associative
  Containers) to LWG 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>12 
      <td>11 
      <td>0 
      <td>0 
      <td>0 
      <td>Unanimous consensus in favor. 
     <tr>
      <td style="padding-bottom: 16px;"> Poll 5: Send <a data-link-type="biblio" href="#biblio-p2136r2">[P2136R2]</a> (<code class="highlight"><c- n>invoke_r</c-></code>) to LWG 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>11 
      <td>12 
      <td>1 
      <td>0 
      <td>0 
      <td>Strong consensus in favor. 
     <tr>
      <td style="padding-bottom: 16px;"> Poll 6: Modify <a data-link-type="biblio" href="#biblio-p1951r0">[P1951R0]</a> (Default Arguments For <code class="highlight"><c- n>pair</c-></code>'s Forwarding
  Constructor) by rebasing the wording on the working draft, and then send the
  revised paper to LWG 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>14 
      <td>9 
      <td>2 
      <td>0 
      <td>0 
      <td>Strong consensus in favor. 
     <tr>
      <td style="padding-bottom: 16px;"> Poll 7: Modify <a data-link-type="biblio" href="#biblio-p2231r0">[P2231R0]</a> (Missing <code class="highlight"><c- k>constexpr</c-></code> In <code class="highlight"><c- n>optional</c-></code> And <code class="highlight"><c- n>variant</c-></code>) by
  adding bumps of the feature test macros <code class="highlight"><c- n>__cpp_lib_optional</c-></code> and <code class="highlight"><c- n>__cpp_lib_variant</c-></code>, and then send the revised paper to LWG 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>19 
      <td>8 
      <td>1 
      <td>0 
      <td>0 
      <td>Strong consensus in favor. 
     <tr>
      <td style="padding-bottom: 16px;"> Poll 8: Send <a data-link-type="biblio" href="#biblio-p0901r8">[P0901R8]</a> (Size Feedback In <code class="highlight"><c- k>operator</c-> <c- k>new</c-></code>) to CWG 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>12 
      <td>10 
      <td>0 
      <td>1 
      <td>0 
      <td>Consensus in favor. 
     <tr>
      <td style="padding-bottom: 16px;"> Poll 9: Send <a data-link-type="biblio" href="#biblio-p1478r6">[P1478R6]</a> (Byte-wise Atomic <code class="highlight"><c- n>memcpy</c-></code>) to LWG for the Concurrency
  TS v2, classified as an addition (<a data-link-type="biblio" href="#biblio-p0592r4">[P0592R4]</a> bucket 3 item). 
      <td>6 
      <td>11 
      <td>2 
      <td>1 
      <td>0 
      <td>Consensus in favor. 
   </table>
   <h2 class="heading settled" data-level="3" id="detailed-results"><span class="secno">3. </span><span class="content">Selected Comments</span><a class="self-link" href="#detailed-results"></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-p0288r7">[P0288R7]</a> The Feature Formerly Known As <code class="highlight"><c- n>any_invocable</c-></code></span><a class="self-link" href="#poll-1"></a></h3>
   <blockquote>
    <p>The name now fits into its surrounding facilities, and gives useful hints
about the properties of the function wrapper.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Consistency between function wrapper types (using the word <code class="highlight"><c- n>function</c-></code>) is
valuable, as is a prefix that distinguishes the semantics of <code class="highlight"><c- n>move_only_function</c-></code> from <code class="highlight"><c- n>function</c-></code>.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>I like this name change. It would be annoying for the "move-only flavor of <code class="highlight"><c- n>function</c-></code>" to have an entirely different name from <code class="highlight"><c- n>function</c-></code>.  Perhaps it
was a bad idea to name <code class="highlight"><c- n>function</c-></code> the way we did, but that ship has sailed,
and <code class="highlight"><c- n>any_invocable</c-></code> makes it worse in two different ways (<code class="highlight"><c- n>function</c-></code> not in
the name, and <code class="highlight"><c- n>any_</c-><c- o>*</c-></code> falsely suggests that <code class="highlight"><c- n>std</c-><c- o>::</c-><c- n>any</c-></code> is involved).</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>The name is good enough, and the facilities are overdue.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>The facility is plainly needed; no one has found a perfect name, but the
proposed name is acceptable.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>I do not much care for this rename, but it works.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>Basically, I am not sure that <code class="highlight"><c- n>move_only_function</c-></code> is the best name that
could be. To me it’s better than <code class="highlight"><c- n>any_invocable</c-></code> and that’s why I am weakly
in favor. But I am trying to look at that from the user perspective. As the
user I have <code class="highlight"><c- n>function</c-></code> and <code class="highlight"><c- n>move_only_function</c-></code>. From the name I cannot get
why I need <code class="highlight"><c- n>move_only_function</c-></code> and when it’s better than just <code class="highlight"><c- n>function</c-></code>. I
understand that it can work with move only callables but I believe <code class="highlight"><c- n>move_only_function</c-></code> should also work with copyable callables So, basically
user question is: "why do I need to use <code class="highlight"><c- n>move_only_function</c-></code> with a copyable
callable?". <code class="highlight"><c- n>unique_function</c-></code> would probably be better name. It’s consistent
with <code class="highlight"><c- n>unique_ptr</c-></code> and still owns the "copy" of the callable underneath (even
if it has a slightly different semantics comparing with <code class="highlight"><c- n>unique_ptr</c-></code>) Or we
should try to find something else.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>While I’m for placing the facility in <code class="highlight"><c- o>&lt;</c-><c- n>functional</c-><c- o>></c-></code>, I think <code class="highlight"><c- n>move_only_function</c-></code> is a unconscionable name: The target need not be move
only (it could be copyable or not movable at all) and the target need not be
a function. If the name is construed as describing the wrapper rather than
the target it’s still inaccurate: <code class="highlight"><c- n>is_function_v</c-><c- o>&lt;</c-><c- n>move_only_function</c-><c- o>&lt;</c-><c- p>...</c-><c- o>>></c-></code> is
always false.</p>
    <p>— Strongly Against</p>
   </blockquote>
   <blockquote>
    <p>In my experience, <code class="highlight"><c- n>any_invocable</c-></code> is used more often than <code class="highlight"><c- n>function</c-></code> - few
callbacks and predicates need or can be copied and therefore, <code class="highlight"><c- n>any_invocable</c-></code> is the more general solution, before even talking about the performances of <code class="highlight"><c- n>any_invocable</c-></code> being much more palatable than that of <code class="highlight"><c- n>function</c-></code>, const
correctness, etc.</p>
    <p>We should therefore nudge people toward <code class="highlight"><c- n>any_invocable</c-></code>, alas, <code class="highlight"><c- n>move_only_function</c-></code> makes the type look like an oddity that should not be
used through an usually long name, which unusually refers to a specific
property of the type.</p>
    <p>Why not <code class="highlight"><c- n>move_only_const_correct_function</c-></code> then?</p>
    <p>Moving away from the <code class="highlight"><c- n>any_</c-><c- o>*</c-></code> will continue to cause naming debates for future
type erased types.</p>
    <p>— Strongly 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-p1642r5">[P1642R5]</a> Freestanding [utilities], [ranges], And [iterators]</span><a class="self-link" href="#poll-2"></a></h3>
   <blockquote>
    <p>Anything that adds to freestanding makes it easier for many segments to use
the C++ library without hacks to get around the limitations.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Anything that is trivial to make freestanding should be, since the
implementation effort is necessary in general regardless.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>Maybe the choice of a <code class="highlight"><c- c1>// freestanding</c-></code> comment is unconventional, but it is
a direction towards a clearer definition of what’s available in a
freestanding environment.</p>
    <p>— Weakly Favor</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-p2216r2">[P2216R2]</a> <code class="highlight"><c- n>std</c-><c- o>::</c-><c- n>format</c-></code> Improvements</span><a class="self-link" href="#poll-3"></a></h3>
   <blockquote>
    <p>Compile time checking and compilation of format strings will increase runtime
performance and catch errors earlier in the design-code-build-test cycle.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>This is major improvement to <code class="highlight"><c- n>format</c-></code> both in terms of safety and binary
footprint. It is a good opportunity to make the API right before major
implementations ship the feature.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Losing the ability to wrap <code class="highlight"><c- n>format</c-></code> is concerning but <code class="highlight"><c- n>vformat</c-></code> is probably
an acceptable workaround for now. There may be a case for exposing the
compile-time checking functionality to users so that they can take advantage
of it in their wrappers.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>Changes like this should come sooner rather than later to minimize the
divergence of practical C++20 implementations.</p>
    <p>— Weakly Favor</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-p2077r2">[P2077R2]</a> Heterogeneous Erasure Overloads For Associative Containers</span><a class="self-link" href="#poll-4"></a></h3>
   <blockquote>
    <p>This fixes an embarrassing issue with associative containers, where the (to
users) obvious code is performance-penalized.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Since <code class="highlight"><c- n>find</c-></code> became heterogeneous the need to <code class="highlight"><c- n>find</c-></code> and then erase on an
iterator was klunky: No reason for erase not to be able to do this directly.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Improves consistency and symmetry of existing interface, as well as
opportunities for efficiency.</p>
    <p>— Weakly Favor</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-p2136r2">[P2136R2]</a> <code class="highlight"><c- n>invoke_r</c-></code></span><a class="self-link" href="#poll-5"></a></h3>
   <blockquote>
    <p>The fact that <code class="highlight"><c- n>is_invocable_r</c-></code> and friends existed without <code class="highlight"><c- n>invoke_r</c-></code> was
weird and led to ad hoc implementations thereof.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Not being able to specify the return type comes up with enough frequency that
fixing it is well worth the effort.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>This improves consistency with the existing type traits and provides a
capability sufficiently useful to already be employed by the standard library
in multiple places.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <h3 class="heading settled" data-level="3.6" id="poll-6"><span class="secno">3.6. </span><span class="content">Poll 6: <a data-link-type="biblio" href="#biblio-p1951r0">[P1951R0]</a> Default Arguments For <code class="highlight"><c- n>pair</c-></code>'s Forwarding Constructor</span><a class="self-link" href="#poll-6"></a></h3>
   <blockquote>
    <p>This fixes something that’s currently broken.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>This fixes the behavior of code that contains a silent performance bug, as
well as allowing certain cases involving non-movable types.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Eliminates a usage gotcha, so an improvement.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <h3 class="heading settled" data-level="3.7" id="poll-7"><span class="secno">3.7. </span><span class="content">Poll 7: <a data-link-type="biblio" href="#biblio-p2231r0">[P2231R0]</a> Missing <code class="highlight"><c- k>constexpr</c-></code> In <code class="highlight"><c- n>optional</c-></code> And <code class="highlight"><c- n>variant</c-></code></span><a class="self-link" href="#poll-7"></a></h3>
   <blockquote>
    <p>More constexpr in generic library code is better than the alternative
especially given the role optional &amp; variant have as "vocabulary types."</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>It’s silly to not consider this a fix for C++20, given the core-language
changes there, but the sooner the better.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>This is an important constexpr extension with good implementation experience.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <h3 class="heading settled" data-level="3.8" id="poll-8"><span class="secno">3.8. </span><span class="content">Poll 8: <a data-link-type="biblio" href="#biblio-p0901r8">[P0901R8]</a> Size Feedback In <code class="highlight"><c- k>operator</c-> <c- k>new</c-></code></span><a class="self-link" href="#poll-8"></a></h3>
   <blockquote>
    <p>Seems like a straightforward improvement: Hiding useful information is the
number one way to have non-zero cost abstractions.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>I feel like the size was always a required result for allocation. I like this
and would like it to become the primary allocation interface.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>This is a good addition to C++. My one concern is that sometimes more space
is allocated for performance, and sometimes memory is so constrained on
embedded systems that extra memory is not wanted unless it would have been
allocated anyway. This interface does not give the caller a way to
differentiate between those two requests.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>I appreciate the situation, but I’m not sure that the solution is at the
right level of abstraction.</p>
    <p>— Weakly Against</p>
   </blockquote>
   <h3 class="heading settled" data-level="3.9" id="poll-9"><span class="secno">3.9. </span><span class="content">Poll 9: <a data-link-type="biblio" href="#biblio-p1478r6">[P1478R6]</a> Byte-wise Atomic <code class="highlight"><c- n>memcpy</c-></code></span><a class="self-link" href="#poll-9"></a></h3>
   <blockquote>
    <p>This is a good candidate for something that should be added to the
Concurrency TS, as we need the feedback to answer the open questions.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>I’ve seen real world use cases where this facility would’ve allowed the code
written to be more correct.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Being able to utilize the (weak) semantics of actual memory operations is
much better than having formal undefined behavior that programmers are
incentivized to ignore.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>Specialized facility but definitely standard library material</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>I generally dislike the TS process, but this does seem to need much wider
feedback after implementation to answer the questions raised in the paper.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>Given the current backlog, putting this feature in a TS with an uncertain
future does not seem conductive to progress.</p>
    <p>— Weakly Against</p>
   </blockquote>
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  <h2 class="no-num no-ref heading settled" id="references"><span class="content">References</span><a class="self-link" href="#references"></a></h2>
  <h3 class="no-num no-ref heading settled" id="informative"><span class="content">Informative References</span><a class="self-link" href="#informative"></a></h3>
  <dl>
   <dt id="biblio-p0288r7">[P0288R7]
   <dd>Ryan McDougall, Matt Calabrese. <a href="https://wg21.link/p0288r7">any_invocable</a>. 3 September 2020. URL: <a href="https://wg21.link/p0288r7">https://wg21.link/p0288r7</a>
   <dt id="biblio-p0592r4">[P0592R4]
   <dd>Ville Voutilainen. <a href="https://wg21.link/p0592r4">To boldly suggest an overall plan for C++23</a>. 25 November 2019. URL: <a href="https://wg21.link/p0592r4">https://wg21.link/p0592r4</a>
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  </dl>