Rewrite determination of postfix/prefix form to use mrow-like definition.

w3c/mathml#184

Author: fred-wang

index.html

@@ -1474,29 +1474,19 @@ <h4>Dictionary-based attributes</h4>
                 on the <a>core operator</a>, then its value is used;
               </li>
               <li>If the embellished operator is the first <a>in-flow</a> child of an
-                <a>unknown MathML element</a>,
-                <a>&lt;math&gt;</a>,
+                <a>mrow-like element</a>,
                 <a>&lt;menclose&gt;</a>,
-                <a>&lt;merror&gt;</a>,
-                <a>&lt;mpadded&gt;</a>,
-                <a>&lt;mphantom&gt;</a>,
-                <a>&lt;mrow&gt;</a>,
-                <a>&lt;msqrt&gt;</a> or
-                <a>&lt;mstyle&gt;</a> with more than one <a>in-flow</a> child
+                <a>&lt;mpadded&gt;</a> or
+                <a>&lt;msqrt&gt;</a> with more than one <a>in-flow</a> child
                 (ignoring all <a>space-like</a> children) then it has
                 form <code>prefix</code>;
               </li>
               <li>Or, if the embellished operator is the last <a>in-flow</a> child of
                 an
-                <a>unknown MathML element</a>,
-                <a><code>&lt;math&gt;</code></a>,
+                <a>mrow-like element</a>,
                 <a><code>&lt;menclose&gt;</code></a>,
-                <a><code>&lt;merror&gt;</code></a>,
-                <a><code>&lt;mpadded&gt;</code></a>,
-                <a><code>&lt;mphantom&gt;</code></a>,
-                <a><code>&lt;mrow&gt;</code></a>,
-                <a><code>&lt;msqrt&gt;</code></a> or
-                <a><code>&lt;mstyle&gt;</code></a>
+                <a><code>&lt;mpadded&gt;</code></a> or
+                <a><code>&lt;msqrt&gt;</code></a>
                 with more than one <a>in-flow</a> child
                 (ignoring all <a>space-like</a> children) then it has
                 form <code>postfix</code>;