New issue from Hewill: "flat_set::erase(iterator) is underconstrained"

Author: Dani-Hub

xml/issue4384.xml

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+<?xml version='1.0' encoding='utf-8' standalone='no'?>
+<!DOCTYPE issue SYSTEM "lwg-issue.dtd">
+
+<issue num="4384" status="New">
+<title>`flat_set::erase(iterator)` is underconstrained
+</title>
+<section>
+<sref ref="[flat.set.defn]"/>
+<sref ref="[flat.multiset.defn]"/>
+</section>
+<submitter>Hewill Kang</submitter>
+<date>25 Sep 2025</date>
+<priority>99</priority>
+
+<discussion>
+<p>
+This is a follow-up of LWG <iref ref="3704"/> since we now have `flat_set` and `flat_multiset`.
+</p>
+</discussion>
+
+<resolution>
+<p>
+This wording is relative to <paper num="N5014"/>.
+</p>
+
+<ol>
+
+<li><p>Modify <sref ref="[flat.set.defn]"/> as indicated:</p>
+
+<blockquote>
+<pre>
+iterator erase(iterator position) <ins>requires (!same_as&lt;iterator, const_iterator&gt;)</ins>;
+iterator erase(const_iterator position);
+</pre>
+</blockquote>
+
+</li>
+
+<li><p>Modify <sref ref="[flat.multiset.defn]"/> as indicated:</p>
+
+<blockquote>
+<pre>
+iterator erase(iterator position) <ins>requires (!same_as&lt;iterator, const_iterator&gt;)</ins>;
+iterator erase(const_iterator position);
+</pre>
+</blockquote>
+
+</li>
+
+</ol>
+</resolution>
+
+</issue>