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  <title>P2435R0: 2021 Summer 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>
<style type="text/css">
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    th, td {
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      padding: 0px 10px;
    }
    th {
      text-align: center;
    }

    del { background: #fcc; color: #000; text-decoration: line-through; }
    ins { background: #cfc; color: #000; }
    blockquote .highlight:not(.idl) { background: initial; margin: initial; padding: 0.5em }
    blockquote ul { background: inherit; }
    blockquote code.highlight:not(.idl) { padding: initial; }
    blockquote c-[a] { color: inherit; } /* Keyword.Declaration */
    blockquote c-[b] { color: inherit; } /* Keyword.Type */
    blockquote c-[c] { color: inherit; } /* Comment */
    blockquote c-[d] { color: inherit; } /* Comment.Multiline */
    blockquote c-[e] { color: inherit; } /* Name.Attribute */
    blockquote c-[f] { color: inherit; } /* Name.Tag */
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    blockquote c-[k] { color: inherit; } /* Keyword */
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    blockquote c-[m] { color: inherit; } /* Literal.Number */
    blockquote c-[n] { color: inherit; } /* Name */
    blockquote c-[o] { color: inherit; } /* Operator */
    blockquote c-[p] { color: inherit; } /* Punctuation */
    blockquote c-[s] { color: inherit; } /* Literal.String */
    blockquote c-[t] { color: inherit; } /* Literal.String.Single */
    blockquote c-[u] { color: inherit; } /* Literal.String.Double */
    blockquote c-[cp] { color: inherit; } /* Comment.Preproc */
    blockquote c-[c1] { color: inherit; } /* Comment.Single */
    blockquote c-[cs] { color: inherit; } /* Comment.Special */
    blockquote c-[kc] { color: inherit; } /* Keyword.Constant */
    blockquote c-[kn] { color: inherit; } /* Keyword.Namespace */
    blockquote c-[kp] { color: inherit; } /* Keyword.Pseudo */
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    blockquote c-[ld] { color: inherit; } /* Literal.Date */
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    blockquote c-[no] { color: inherit; } /* Name.Constant */
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    blockquote c-[nn] { color: inherit; } /* Name.Namespace */
    blockquote c-[py] { color: inherit; } /* Name.Property */
    blockquote c-[ow] { color: inherit; } /* Operator.Word */
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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 4f053d00e, updated Tue Aug 10 14:13:32 2021 -0700" name="generator">
  <link href="https://wg21.link/P2435" rel="canonical">
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<style>
table, th, tr, td {
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}
@media (prefers-color-scheme: dark) {
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  <div class="head">
   <p data-fill-with="logo"></p>
   <h1 class="p-name no-ref" id="title">P2435R0<br>2021 Summer 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="2021-09-09">2021-09-09</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_p2435_2021_summer_library_evolution_poll_outcomes/blob/main/2021_summer_library_evolution_poll_outcomes.bs">GitHub</a>
     <dt>Issue Tracking:
     <dd><a href="https://github.com/brycelelbach/wg21_p2435_2021_summer_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>[P2138R4]</span> Rules of Design &lt;=> Wording Engagement</span></a>
      <li><a href="#poll-2"><span class="secno">3.2</span> <span class="content">Poll 2: <span>[P2372R1]</span> Fixing Locale Handling In Chrono Formatters</span></a>
      <li><a href="#poll-3"><span class="secno">3.3</span> <span class="content">Poll 3: <span>[P1206R6]</span> <code class="highlight"><c- n>ranges</c-><c- o>::</c-><c- n>to</c-></code></span></a>
      <li><a href="#poll-4"><span class="secno">3.4</span> <span class="content">Poll 4: <span>[P0533R8]</span> <code class="highlight"><c- k>constexpr</c-></code> For <code class="highlight"><c- o>&lt;</c-><c- n>cmath</c-><c- o>></c-></code> And <code class="highlight"><c- o>&lt;</c-><c- n>cstdlib</c-><c- o>></c-></code></span></a>
      <li><a href="#poll-5"><span class="secno">3.5</span> <span class="content">Poll 5: <span>[P2273R2]</span> Making <code class="highlight"><c- n>unique_ptr</c-></code> <code class="highlight"><c- k>constexpr</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 Summer 2021, the C++ Library Evolution group conducted a series of electronic
  decision polls <a data-link-type="biblio" href="#biblio-p2333r0">[P2333R0]</a>.
This paper provides the results of those polls and summarizes the results.</p>
   <p>In total, 36 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: Make a joint Library Evolution and Evolution plenary to adopt <a data-link-type="biblio" href="#biblio-p2138r4">[P2138R4]</a> (Rules of Design &lt;=> Wording Engagement) as the official process of
  the C++ Evolution groups. 
      <td>5 
      <td>14 
      <td>2 
      <td>6 
      <td>6 
      <td>No consensus. 
     <tr>
      <td style="padding-bottom: 16px;"> Poll 2: Send <a data-link-type="biblio" href="#biblio-p2372r1">[P2372R1]</a> (Fixing Locale Handling In Chrono Formatters) 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>21 
      <td>10 
      <td>0 
      <td>0 
      <td>0 
      <td>Unanimous consenus in favor. 
     <tr>
      <td style="padding-bottom: 16px;"> Poll 3: Send <a data-link-type="biblio" href="#biblio-p1206r6">[P1206R6]</a> (<code class="highlight"><c- n>ranges</c-><c- o>::</c-><c- n>to</c-></code>) to Library Working Group for C++23,
  classified as an addition (<a data-link-type="biblio" href="#biblio-p0592r4">[P0592R4]</a> bucket 3 item). 
      <td>19 
      <td>9 
      <td>0 
      <td>0 
      <td>0 
      <td>Unanimous consenus in favor. 
     <tr>
      <td style="padding-bottom: 16px;"> Poll 4: Send <a data-link-type="biblio" href="#biblio-p0533r8">[P0533R8]</a> (<code class="highlight"><c- k>constexpr</c-></code> For <code class="highlight"><c- o>&lt;</c-><c- n>cmath</c-><c- o>></c-></code> And <code class="highlight"><c- o>&lt;</c-><c- n>cstdlib</c-><c- o>></c-></code>) to Library
  Working Group for C++23, classified as an addition (<a data-link-type="biblio" href="#biblio-p0592r4">[P0592R4]</a> bucket 3 item). 
      <td>15 
      <td>13 
      <td>2 
      <td>1 
      <td>0 
      <td>Consensus in favor. 
     <tr>
      <td style="padding-bottom: 16px;"> Poll 5: Send <a data-link-type="biblio" href="#biblio-p2273r2">[P2273R2]</a> (Making <code class="highlight"><c- n>unique_ptr</c-></code> <code class="highlight"><c- k>constexpr</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>17 
      <td>16 
      <td>0 
      <td>0 
      <td>0 
      <td>Unanimous consenus 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-p2138r4">[P2138R4]</a> Rules of Design &lt;=> Wording Engagement</span><a class="self-link" href="#poll-1"></a></h3>
   <blockquote>
    <p>I don’t know what the solution is, but this document further solidifies and
ingrains our current patterns and processes. Which would be fine, except they
are not.</p>
    <p>Our current process is an exclusionary set of hurdles for anyone with out the
time and money to navigate our gauntlet. This proposal encourages the
gauntlet and possibly even adds more hurtles.</p>
    <p>Now, there should be hurtles. Particularly since we avoid compatibility
breaks, we need to get things right the first time. Decisions are
approximately forever.</p>
    <p>Also, we do too much to be able to keep track of everything, so pause points
that give people time to review and demarcate "this really is moving forward,
you better look at it", help those of us whom can’t be in multiple rooms at
once. (The alternative here is to trust your subgroups)</p>
    <p>So I’m conflicted.</p>
    <p>— Weakly Against</p>
   </blockquote>
   <blockquote>
    <p>This paper will have disastrous consequences on WG21 that the committee, its
members, and proposal writers are wholly unprepared to deal with. If the idea
is that, instead of an open process, we should endeavor to make improving C++
so difficult that it makes COBOL’s submission process look easy or similar by
comparison, then I suppose this paper is "working as intended". If this paper
moves through to plenary and is adopted I can see several people simply not
participating in C++ anymore.</p>
    <p>— Strongly Against</p>
   </blockquote>
   <blockquote>
    <p>It seems as a freezing current bad process which detract people and hinders
getting new committee members.</p>
    <p>— Weakly Against</p>
   </blockquote>
   <blockquote>
    <p>I’m in favor of strengthening, clarifying, and formalizing the criteria for
papers to advance, as I think it will improve quality. However, I worry that
this may add complexity to our process, which is already outdated and arcane.</p>
    <p>— Neutral</p>
   </blockquote>
   <blockquote>
    <p>While I think this describes current practice reasonably well, which is
helpful, (thus I weakly favor) I’m concerned that the this is might increase
the perceived barriers to entry to contributing to WG21.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>The problems this process aims to address are plainly real: lots of our
limited wording-group bandwidth is consumed by reviewing wording that is
unusably incomplete, and disagreements about the design intent of papers
approved by design groups have been very problematic. Also, distinguishing
papers with approved designs but no wording is simply good process
engineering, since they can’t be reviewed yet. However, it is not clear that
the design groups can reliably evaluate whether wording implements the design
intent without duplicating the wording group’s work. Also, wordsmiths' time
is also limited, and while there’s no requirement that they agree with a
proposal to review its initial wording, the natural tendency would be to
spend their limited time on those that they favor. It doesn’t seem right to
subject proposals to that sort of pocket veto. A wording review group would
of course be well within its rights to suspect that a paper’s wording might
not be ready and deputize one of its members to ascertain that fact and
communicate it to the author (who would be just as capable of securing help
with it as they would be under this proposal).</p>
    <p>While the paper discusses means of accelerating urgent proposals, it is
nonetheless plain that this process would in general extend the review
process. That’s not intrinsically undesirable, but lengthening the process by
fiat (rather than, say, because implementation concerns have been raised) is
of questionable value. It’s a little unreasonable to require a notional
author of one paper to attend every in-person meeting (when those are
happening) for years in case one of the many reviews for it occurs at one of
them. In particular, having a "park for further design feedback" stage in
addition to a "Tentatively Wording" stage seems gratuitous.</p>
    <p>— Strongly Against</p>
   </blockquote>
   <blockquote>
    <p>This proposal will have the following effects if adopted by LEWG:</p>
    <ol>
     <li data-md>
      <p>It will cement a complex and baroque process even further into WG21.</p>
     <li data-md>
      <p>It will increase the already high gatekeeper discrimination of proposals.</p>
     <li data-md>
      <p>It will allow LWG to discriminate against LEWG by discounting their consensus findings.</p>
     <li data-md>
      <p>It will place unbounded decision power on individuals with undefined credentials.</p>
    </ol>
    <p>Hence it is unconscionable of me to vote anything but strongly against.</p>
    <p>— Strongly Against</p>
   </blockquote>
   <blockquote>
    <p>It’s not clear to me that injecting more delay into the process is going to
result in more actionable feedback and therefore a better quality standard.
It is also quite possible that the stringent gatekeeping would discourage
participation and therefore useful feedback.</p>
    <p>Additionally, I have not found LEWG wording review to be a worthwhile use of
valuable telecon time.</p>
    <p>— Weakly Against</p>
   </blockquote>
   <blockquote>
    <p>I’m not a fan of the requirement that wording must exist to advance out of
(L)EWG. My experience suggests that this actively causes harm. What we’ve
seen is that authors now see that they need wording, so they spend time
writing wording. The problem is, the wording is often bad anyway -- so you
end up with a paper with potentially pages of wording that doesn’t really
help explain the design because the authors spent time writing bad wording
that could have been spent writing clearer motivation, examples, prose, etc.
Or the author knows that they can’t write wording, so they go try to get
wording review for a paper that may just not be a good design, which ends up
not being a good use of the wordsmith’s time either. Even when the wording is
fine, it’s just actively distracting from the discussion - which should be at
this point about the design. So you get comments about wording issues that
are, frankly, completely irrelevant and wholly unproductive. I think the best
thing you could say about requiring wording is that it’s simply a waste of
time in that the author had to spend their time producing wording earlier
than necessary. The presented problem (papers show up to CWG/LWG with poor
wording) can be solved by just requiring that papers show up to CWG/LWG with
good wording - requiring EWG/LEWG to see it seems like a completely needless
extra step in the process.</p>
    <p>— Weakly Against</p>
   </blockquote>
   <blockquote>
    <p>I believe this will do a lot more harm than good, and try to solve non-problems.</p>
    <p>While C++20 finalization might have been somewhat hectic, our ability to
quickly fix issues encountered in 2019 and 2020 is a big part of the quality
of the final product. More stiffness is the last thing we need.</p>
    <p>This paper, by proposing a constant amount of process regardless of feature
size is negatively affecting incremental improvements and small papers.</p>
    <p>While many are excited by concepts and pattern matching or executors,  we
should not discourage papers that propose small incremental improvements like
a contain method on a string, or making std::move nodiscard.</p>
    <p>If our process is such that papers can be "too small to be worth our time"
there is an issue with our process. And while we should be mindful of our
ever-growing backlog, I do not believe making it harder for first-time
contributors to participate is a good way to solve this problem.</p>
    <p>If it takes 12+ months to add a small uncontroversial function, it simply
won’t be done and will leave c++ with rough edges. Same for specification
cleanups. New contributors will stop showing up.</p>
    <p>I trust the chair and our peers to ask of authors an amount of work that is
proportional to the perceived risk. I trust the existing process to be good
enough (nothing terrible happened in 20, in fact, it is a very successful
version). And I trust that being flexible gives the committee the opportunity
to improve and learn instead of settings in stone an imperfect process.
Enshrining some set of rules gives us less opportunity to improve and adapt
to a workload.</p>
    <p>I hope we can find ways to make the process more accessible, rather than
less. Small group wording reviews, wording guidances, etc would be a better
way to reduce the working group workloads. Asking new contributors to find a
wordsmith can be intimidating.</p>
    <p>Maybe one waiting period would be useful, but having to wait between design
and wording, and wording and plenary, while also asking the paper to leave
design with wording adds nothing. One period is enough. I do not believe that
giving more time to implementers or users to give feedback will stop people
from waking up in plenary. We know from experience that more time != more
feedback. In a face-to-face meeting context, this might also mean that an
author has to travel twice, which might not be possible. Maybe we can
advertise the status of papers more clearly so that no one is surprised.</p>
    <p>— Strongly Against</p>
   </blockquote>
   <blockquote>
    <p>It would indeed be useful to recognize the importance of providing wording. I
fear we might find our best wordsmiths overflowing with requests, however,
which explains why I used "weakly" instead of "strongly" for my vote.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>Having been asked about the process for getting a proposal into the standard,
I’m happy to have documentation to which I can point. I do have minor
concerns about finding wordsmiths, but I feel that can be worked out later if
it becomes truly problematic.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>We need a checklist and a description for how proposals flow through the
committee; it’s unreasonable to continue to do that in an ad-hoc manner.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>I very much like the process clarification and agree this has been the
historical golden standard.</p>
    <p>— Strongly Favor</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-p2372r1">[P2372R1]</a> Fixing Locale Handling In Chrono Formatters</span><a class="self-link" href="#poll-2"></a></h3>
   <blockquote>
    <p>Better to fix it now than live with it for 30 years.</p>
    <p>IMO, almost anything in C++20 is open for change/correction until C++23 is
released. Adoption isn’t that fast, and any code using new features must be
new code, and new code isn’t hard to fix.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>We want to enable locale-independent formatting as much as possible, while
also making explicit locale-dependent formatting possible where needed.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>It’s unfortunate that we shipped this broken, but we can’t reclaim
consistency unless we deal with this now, so we should do so.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>This fixes an unpleasant inconsistency in <code class="highlight"><c- n>std</c-><c- o>::</c-><c- n>format</c-></code>. I only wish the fix
had come two years ago; I dislike continuing to change C++20 after it has
shipped, as it adds uncertainty for implementers</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>Still not enjoying retroactive application [of changes to C++20].</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-p1206r6">[P1206R6]</a> <code class="highlight"><c- n>ranges</c-><c- o>::</c-><c- n>to</c-></code></span><a class="self-link" href="#poll-3"></a></h3>
   <blockquote>
    <p>Converting a range to a concrete container should be easier, and this makes
it so.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>A long-standing complaint from our developers comes from the verbosity of
converting one container to another. The additions proposed here should help
alleviate some of those complaints while also making ranges more attractive
for newcomers.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>I’ve recently worked on a project that started using boost::string_view
heavily (C++17 wasn’t available). I have become painfully aware of how
awkward it is to have views and ranges without convenient conversions between
a view and a container. We need something like ranges::to in the standard.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>The bullet points in the specification of ranges::to don’t allow for
construction using ranges::begin(r) and ranges::end(r), even though that is
described as one of the options earlier in the document.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>The new from_range_t design is a lot more extensible, easy to diagnose, and
efficient.</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-p0533r8">[P0533R8]</a> <code class="highlight"><c- k>constexpr</c-></code> For <code class="highlight"><c- o>&lt;</c-><c- n>cmath</c-><c- o>></c-></code> And <code class="highlight"><c- o>&lt;</c-><c- n>cstdlib</c-><c- o>></c-></code></span><a class="self-link" href="#poll-4"></a></h3>
   <blockquote>
    <p>It is a significant improvement in applicability of constexpr in real-world
projects dealing with FP arithmetic.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>The function proposed in the paper, are indeed looking to be "simple", i.e.
not more complicated as few operators. Not including them, will lead to
user’s implementation, that may lead to more subtle bugs.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>The worries seemed to be about implementability with respect to errno, but
that aspect of the problem is now more documented and there seems to be
implementation experience on at least one library</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Despite the many concerns raised, I still don’t think this makes the status
quo any worse as regard to constexpr floating point inconsistencies between
compile-time and runtime. In fact, this might encourage implementers to
guarantee that the maths functions are correctly rounded at compile-time
regardless of the target behavior, like GCC does. This will allow many
look-up tables to be computed at compile-time instead of relying on code
generators.</p>
    <p>People will rely on target maths can make sure their operations are not
constant-folded. We should encourage more work in this area though!</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>I like P0533, however, sqrt should also be constexpr. It deserves special
treatment because the IEEE standard gives it special treatment: it is the
only operation, other than arithmetic operators and std::fma, required to be
exact (see IEEE 754-2008, sec 5.4.1). ("Exact" meaning that its error is less
than 0.5 ulp)</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>Not totally convinced this is the best strategy, but I don’t have a better
suggestion.</p>
    <p>— Neutral</p>
   </blockquote>
   <blockquote>
    <p>The motivation is there, but I’m uncomfortable building more on top of the
shaky foundation of constexpr floating point. We need a paper and plenary
approval on which things WG21 wants out of constexpr floating point. Do we
want compile time and runtime to produce the same results (this would be
hard). Do we want the same source to result in the same compile time results
across multiple implementations (i.e. do we want compile time calculations
portable)? Do we want always-precise results out of compile time
calculations? We don’t have a uniform answer here, and until we do, I can’t
be in favor of the proposal.</p>
    <p>I’m also not thrilled with the implementation experience on this proposal.
Something besides GCCs constant folding implementation really ought to be
provided. The existence of builtins isn’t sufficient.</p>
    <p>— Weakly 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-p2273r2">[P2273R2]</a> Making <code class="highlight"><c- n>unique_ptr</c-></code> <code class="highlight"><c- k>constexpr</c-></code></span><a class="self-link" href="#poll-5"></a></h3>
   <blockquote>
    <p>P2273’s intro says it all: without P2273, using new or delete in a
constexpr-context would force us back to a pre-c++11 memory-management era.</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>There seems to be no reason not to do this anymore (I’ve faced a situation
where this would have been useful just last week and was surprised it did not
work as I expected it to).</p>
    <p>— Strongly Favor</p>
   </blockquote>
   <blockquote>
    <p>It continues to be a goal to make compile-time programming as similar as
possible to runtime programming, to allow as much code as possible to be
shared between the two environments. There is no reason to encourage the use
of undesirable constructs like manual memory management by making the
preferred replacements unavailable during constant evaluation.</p>
    <p>— Weakly Favor</p>
   </blockquote>
   <blockquote>
    <p>This seems a straightforward change enabling some use cases; but the paper
itself does appear to lack strong motivation so I only weakly support it.</p>
    <p>— Weakly Favor</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-p0533r8">[P0533R8]
   <dd>Oliver Rosten, Edward Rosten. <a href="https://wg21.link/p0533r8"><cite>constexpr for cmath and cstdlib</cite></a>. 24 June 2021. URL: <a href="https://wg21.link/p0533r8">https://wg21.link/p0533r8</a>
   <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-p1206r6">[P1206R6]
   <dd>Corentin Jabot, Eric Niebler, Casey Carter. <a href="https://wg21.link/p1206r6"><cite>Conversions from ranges to containers</cite></a>. 3 August 2021. URL: <a href="https://wg21.link/p1206r6">https://wg21.link/p1206r6</a>
   <dt id="biblio-p2138r4">[P2138R4]
   <dd>Ville Voutilainen. <a href="https://wg21.link/p2138r4"><cite>Rules of Design&lt;=>Specification engagement</cite></a>. 19 April 2021. URL: <a href="https://wg21.link/p2138r4">https://wg21.link/p2138r4</a>
   <dt id="biblio-p2273r2">[P2273R2]
   <dd>Andreas Fertig. <a href="https://wg21.link/p2273r2"><cite>Making std::unique_ptr constexpr</cite></a>. 5 July 2021. URL: <a href="https://wg21.link/p2273r2">https://wg21.link/p2273r2</a>
   <dt id="biblio-p2333r0">[P2333R0]
   <dd>Bryce Adelstein Lelbach. <a href="https://wg21.link/p2333r0"><cite>2021 Winter Library Evolution Poll Outcomes</cite></a>. 12 March 2021. URL: <a href="https://wg21.link/p2333r0">https://wg21.link/p2333r0</a>
   <dt id="biblio-p2372r1">[P2372R1]
   <dd>Victor Zverovich, Corentin Jabot. <a href="https://wg21.link/p2372r1"><cite>Fixing locale handling in chrono formatters</cite></a>. 13 May 2021. URL: <a href="https://wg21.link/p2372r1">https://wg21.link/p2372r1</a>
  </dl>