New issue from Thomas: "Clarify whether arithmetic expressions in [nu…

…meric.sat.func] are mathematical or C+"

xml/issue4030.xml

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+<?xml version='1.0' encoding='utf-8' standalone='no'?>
+<!DOCTYPE issue SYSTEM "lwg-issue.dtd">
+
+<issue num="4030" status="New">
+<title>Clarify whether arithmetic expressions in [numeric.sat.func] are mathematical or C++</title>
+<section><sref ref="[numeric.sat.func]"/></section>
+<submitter>Thomas K&ouml;ppe</submitter>
+<date>18 Dec 2023</date>
+<priority>99</priority>
+
+<discussion>
+<p>
+During the application of <paper num="P0543R0"/>, "Saturation arithmetic", it was pointed out that it 
+might not be entirely clear what we want something like "<tt>x</tt> + <tt>y</tt>" to mean. The paper does not 
+suggest any formatting for those symbols, and a non-normative note explains that the intention is for 
+the expression to be considered mathematically.
+<p/>
+I wonder if this is clear enough. Notes are not normative, and the document "shall be usable without notes". 
+I have formatted this as <tt>$\tcode{x} + \tcode{y}$</tt> throughout, i.e. the variables are in code font, 
+but the symbol is maths, not code. This is quite subtle. (See also 
+<a href="https://github.com/cplusplus/draft/pull/6686">GitHub discussion</a>.)
+<p/>
+I think it would be an improvement if we simply made the note not be a note. It seems to contain entirely reasonable, mandatory content.
+</p>
+</discussion>
+
+<resolution>
+<p>
+This wording is relative to <paper num="N4971"/>.
+</p>
+
+<ol>
+
+<li><p>Modify <sref ref="[numeric.sat.func]"/> as indicated:</p>
+
+<blockquote>
+<p>
+-1- <del>[<i>Note 1</i>:</del> In the following descriptions, an arithmetic operation is performed as a mathematical 
+operation with infinite range and then it is determined whether the mathematical result fits into the result type. 
+<del>&mdash; <i>end note</i>]</del>
+</p>
+</blockquote>
+
+</li>
+
+</ol>
+
+
+</resolution>
+
+</issue>