<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>Issue 281: std::min() and max() requirements overly restrictive</title>
<meta property="og:title" content="Issue 281: std::min() and max() requirements overly restrictive">
<meta property="og:description" content="C++ library issue. Status: CD1">
<meta property="og:url" content="https://cplusplus.github.io/LWG/issue281.html">
<meta property="og:type" content="website">
<meta property="og:image" content="http://cplusplus.github.io/LWG/images/cpp_logo.png">
<meta property="og:image:alt" content="C++ logo">
<style>
  p {text-align:justify}
  li {text-align:justify}
  pre code.backtick::before { content: "`" }
  pre code.backtick::after { content: "`" }
  blockquote.note
  {
    background-color:#E0E0E0;
    padding-left: 15px;
    padding-right: 15px;
    padding-top: 1px;
    padding-bottom: 1px;
  }
  ins {background-color:#A0FFA0}
  del {background-color:#FFA0A0}
  table.issues-index { border: 1px solid; border-collapse: collapse; }
  table.issues-index th { text-align: center; padding: 4px; border: 1px solid; }
  table.issues-index td { padding: 4px; border: 1px solid; }
  table.issues-index td:nth-child(1) { text-align: right; }
  table.issues-index td:nth-child(2) { text-align: left; }
  table.issues-index td:nth-child(3) { text-align: left; }
  table.issues-index td:nth-child(4) { text-align: left; }
  table.issues-index td:nth-child(5) { text-align: center; }
  table.issues-index td:nth-child(6) { text-align: center; }
  table.issues-index td:nth-child(7) { text-align: left; }
  table.issues-index td:nth-child(5) span.no-pr { color: red; }
  @media (prefers-color-scheme: dark) {
     html {
        color: #ddd;
        background-color: black;
     }
     ins {
        background-color: #225522
     }
     del {
        background-color: #662222
     }
     a {
        color: #6af
     }
     a:visited {
        color: #6af
     }
     blockquote.note
     {
        background-color: rgba(255, 255, 255, .10)
     }
  }
</style>
</head>
<body>
<hr>
<p><em>This page is a snapshot from the LWG issues list, see the <a href="lwg-active.html">Library Active Issues List</a> for more information and the meaning of <a href="lwg-active.html#CD1">CD1</a> status.</em></p>
<h3 id="281"><a href="lwg-defects.html#281">281</a>. std::min() and max() requirements overly restrictive</h3>
<p><b>Section:</b> 26.8.9 <a href="https://wg21.link/alg.min.max">[alg.min.max]</a> <b>Status:</b> <a href="lwg-active.html#CD1">CD1</a>
 <b>Submitter:</b> Martin Sebor <b>Opened:</b> 2000-12-02 <b>Last modified:</b> 2016-01-28</p>
<p><b>Priority: </b>Not Prioritized
</p>
<p><b>View other</b> <a href="lwg-index-open.html#alg.min.max">active issues</a> in [alg.min.max].</p>
<p><b>View all other</b> <a href="lwg-index.html#alg.min.max">issues</a> in [alg.min.max].</p>
<p><b>View all issues with</b> <a href="lwg-status.html#CD1">CD1</a> status.</p>
<p><b>Duplicate of:</b> <a href="lwg-closed.html#486" title="min/max CopyConstructible requirement is too strict (Status: Dup)">486</a></p>
<p><b>Discussion:</b></p>
<p>The requirements in 25.3.7, p1 and 4 call for T to satisfy the
requirements of <code>LessThanComparable</code> ( [lessthancomparable])
and <code>CopyConstructible</code> (16.4.4.2 <a href="https://wg21.link/utility.arg.requirements">[utility.arg.requirements]</a>).
Since the functions take and return their arguments and result by
const reference, I believe the <code>CopyConstructible</code> requirement
is unnecessary.
</p>


<p id="res-281"><b>Proposed resolution:</b></p>
<p>Remove the <code>CopyConstructible</code> requirement. Specifically, replace
25.3.7, p1 with</p>
<p><b>-1- Requires:</b> Type T is <code>LessThanComparable</code> 
( [lessthancomparable]).
</p>
<p>and replace 25.3.7, p4 with</p>
<p><b>-4- Requires:</b> Type T is <code>LessThanComparable</code> 
( [lessthancomparable]).
</p>




</body>
</html>
