Added issue about the definition of 'mod' in calc().

Author: tabatkins

css3-values/Overview.html

@@ -1324,7 +1324,11 @@ <h3 id=calc><span class=secno>9.1. </span> Mathematical Expressions:
    href="#frequency-value"><code>&lt;frequency&gt;</code></a>, <a
    href="#angle-value"><code>&lt;angle&gt;</code></a>, <a
    href="#time-value"><code>&lt;time&gt;</code></a>, or <a
-   href="#number-value"><code>&lt;number&gt;</code></a> values are allowed.</p>
+   href="#number-value"><code>&lt;number&gt;</code></a> values are allowed.
+
+  <p class=issue>What definition of "mod" do we use? Should &lsquo;<code
+   class=css>calc(-3mod5)</code>&rsquo; return &lsquo;<code
+   class=css>-3</code>&rsquo; or &lsquo;<code class=css>2</code>&rsquo;?</p>
   <!-- http://lists.w3.org/Archives/Public/www-style/2010May/0001.html
 	This has notes on how we should handle things when calc() is extended to 
 	handle unit mult/div. -->

css3-values/Overview.src.html

@@ -885,6 +885,9 @@ <h3 id="calc">
 	<code>&lt;number&gt;</code>
 	values are allowed.</p>
 
+	<p class='issue'>What definition of "mod" do we use?  Should ''calc(-3mod5)''
+	return ''-3'' or ''2''?</p>
+
 	<!-- http://lists.w3.org/Archives/Public/www-style/2010May/0001.html
 	This has notes on how we should handle things when calc() is extended to 
 	handle unit mult/div. -->