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<title>Issue 3373: {to,from}_chars_result and format_to_n_result need the
 "we really mean what we say" wording</title>
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 &quot;we really mean what we say&quot; wording">
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<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#C++20">C++20</a> status.</em></p>
<h3 id="3373"><a href="lwg-defects.html#3373">3373</a>. <code>{to,from}_chars_result</code> and <code>format_to_n_result</code> need the
 "we really mean what we say" wording</h3>
<p><b>Section:</b> 28.2.1 <a href="https://wg21.link/charconv.syn">[charconv.syn]</a>, 28.5.1 <a href="https://wg21.link/format.syn">[format.syn]</a> <b>Status:</b> <a href="lwg-active.html#C++20">C++20</a>
 <b>Submitter:</b> Tim Song <b>Opened:</b> 2020-01-16 <b>Last modified:</b> 2021-02-25</p>
<p><b>Priority: </b>0
</p>
<p><b>View all other</b> <a href="lwg-index.html#charconv.syn">issues</a> in [charconv.syn].</p>
<p><b>View all issues with</b> <a href="lwg-status.html#C++20">C++20</a> status.</p>
<p><b>Discussion:</b></p>
<p>
To ensure that <code>to_chars_result</code>, <code>from_chars_result</code>, and
<code>format_to_n_result</code> can be used in structured bindings, they need the
special wording we use to negate the general library permission to add private
data members and bases.
</p>

<p><i>[2020-02-01 Status set to Tentatively Ready after six positive votes on the reflector.]</i></p>



<p id="res-3373"><b>Proposed resolution:</b></p>
<p>This wording is relative to <a href="https://wg21.link/n4842">N4842</a>.</p>

<ol>
<li><p>Add a paragraph at the end of 28.2.1 <a href="https://wg21.link/charconv.syn">[charconv.syn]</a> as follows:</p>

<blockquote>
<p>
-?- The types <code>to_chars_result</code> and <code>from_chars_result</code> have the
data members and special members specified above. They have no base classes or
members other than those specified.
</p>
</blockquote>
</li>

<li><p>Add a paragraph at the end of 28.5.1 <a href="https://wg21.link/format.syn">[format.syn]</a> as follows:</p>

<blockquote>
<p>
-1- The class template <code>format_to_n_result</code> has the template parameters,
data members, and special members specified above. It has no base classes or
members other than those specified.
</p>
</blockquote>
</li>
</ol>





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