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<title>Issue 193: Heap operations description incorrect</title>
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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#TC1">TC1</a> status.</em></p>
<h3 id="193"><a href="lwg-defects.html#193">193</a>. Heap operations description incorrect</h3>
<p><b>Section:</b> 26.8.8 <a href="https://wg21.link/alg.heap.operations">[alg.heap.operations]</a> <b>Status:</b> <a href="lwg-active.html#TC1">TC1</a>
 <b>Submitter:</b> Markus Mauhart <b>Opened:</b> 1999-09-24 <b>Last modified:</b> 2024-01-25</p>
<p><b>Priority: </b>Not Prioritized
</p>
<p><b>View all other</b> <a href="lwg-index.html#alg.heap.operations">issues</a> in [alg.heap.operations].</p>
<p><b>View all issues with</b> <a href="lwg-status.html#TC1">TC1</a> status.</p>
<p><b>Duplicate of:</b> <a href="lwg-closed.html#216" title="setbase manipulator description flawed (Status: Dup)">216</a></p>
<p><b>Discussion:</b></p>
<p>25.3.6 [lib.alg.heap.operations] states two key properties of a heap [a,b), the first of them
is<br/>
<br/>
&nbsp;&nbsp;&nbsp; "(1) *a is the largest element"<br/>
<br/>
I think this is incorrect and should be changed to the wording in the proposed
resolution.</p>
<p>Actually there are two independent changes:</p>
<blockquote>
  <p>A-&quot;part of largest equivalence class" instead of "largest", cause 25.3
  [lib.alg.sorting] asserts "strict weak ordering" for all its sub clauses.</p>
  <p>B-Take 'an oldest' from that equivalence class, otherwise the heap functions  could not be used for a
  priority queue as explained in 23.2.3.2.2 [lib.priqueue.members] (where I assume that a "priority queue" respects  priority AND time).</p>
</blockquote>


<p id="res-193"><b>Proposed resolution:</b></p>
<p>Change 26.8.8 <a href="https://wg21.link/alg.heap.operations">[alg.heap.operations]</a> property (1) from:</p>
<blockquote>
  <p>(1) *a is the largest element</p>
</blockquote>
<p>to:</p>
<blockquote>
  <p>(1) There is no element greater than <code>*a</code></p>
</blockquote>





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