[r2004-07-03 09:03:26 by afrisch] Manual

Original author: afrisch
Date: 2004-07-03 09:03:26+00:00

web/manual/types_patterns.xml

@@ -304,18 +304,24 @@ which represents concatenation.
 <code>%%R%%+?</code>,
 <code>%%R%%*?</code>. For types, there is no distinction in semantics between
 greedy and ungreedy. </li>
- <li>A sequence capture variable <code>%%x%%::%%R%%</code>.
+ <li>A sequence capture variable <code>%%x%%::%%R%%</code>
+(only for patterns, of course).
 The semantics is to capture in <code>%%x%%</code>  the subsequence
 matched by <code>%%R%%</code>. The same sequence capture variable
 can appear several times inside a regular expression, including
 under repetition operators; in that case, all the corresponding
-subsequences are concatenated together.
+subsequences are concatenated together. Two instances of the
+same sequence capture variable cannot be nested, as in
+<code>[x :: (1 x :: Int)]</code>.
 <br/>
 Note the difference between <code>[ x::Int ]</code> and
 <code>[ (x &amp; Int) ]</code>. Both accept sequences made of a single
 integer, but the first one binds <code>x</code> to a sequence
 (of a single integer), whereas the second one binds it to
 the integer itself.</li>
+<li>
+Grouping <code>(%%R%%)</code>. E.g.: <code>[ x::(Int Int) y ]</code>.
+</li>
 </ul>
 
 <p>