Differences

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--- syntax [2011/09/26 09:53] – created Patrick Michel
+++ syntax [2012/07/25 12:14] (current) – Patrick Michel
@@ Line 1: / Line 1: @@
 ====== XCend File Syntax ======
+<fs 150%>The page is incomplete and outdated</fs>.
 A XCend file consists mainly of a ''pattern'', which has to be an ''element'' at the root:
@@ Line 9: / Line 11: @@
 </code>
-In general a pattern is a sequence of ''element'' and ''attribute'' declarations:
+In general, a pattern is a sequence of ''element'' and ''attribute'' declarations:
 <code xcend>
-element <name> (?|*|+)? {
+element <name> (?|* (<name>)?)? {
   <body>
 }
@@ Line 23: / Line 25: @@
 </code>
-Elements can be optional, repeated or repeated but have to appear at least once. Attributes can only be optional.
+Elements can be //optional// or //repeated//, attributes can only be optional. For repeated elements, the implicit disambiguation identifier can be renamed and accessed like a normal attribute.
+You can also specify choices between elements and attributes, which means that only one has to exist.
+<code xcend>
+element choice {
+  element a {} | element b {} | attribute c {}
+}
+</code>
 A body can either be empty, pattern, type or enumeration declaration:
 <code xcend>
-element types {
+element empty {
 }