geirm 00/11/01 15:13:03
Modified: src/java/org/apache/velocity/runtime/parser Parser.jjt
Log:
No functional change. (Started documenting.)
Resubmitting to ensure current Parser code (.jjt, .jj, .java) in synch. (.jj and
.java snuck in from jason)
Revision Changes Path
1.13 +20 -1
jakarta-velocity/src/java/org/apache/velocity/runtime/parser/Parser.jjt
Index: Parser.jjt
===================================================================
RCS file:
/home/cvs/jakarta-velocity/src/java/org/apache/velocity/runtime/parser/Parser.jjt,v
retrieving revision 1.12
retrieving revision 1.13
diff -u -r1.12 -r1.13
--- Parser.jjt 2000/11/01 01:10:34 1.12
+++ Parser.jjt 2000/11/01 23:13:00 1.13
@@ -52,6 +52,25 @@
* <http://www.apache.org/>.
*/
+/*
+ * Background
+ * ----------
+ *
+ * VTL == Velocity Template Language
+ *
+ * The problem with parsing VTL is that an input stream consists generally of
little
+ * bits of VTL mixed in with 'other stuff' (hereafter referred to as 'schmoo').
Unlike
+ * other languages, like C or Java, where the parser can punt whenever it
encounters
+ * input that doesn't conform to the grammar, the VTL parser can't do that.
+ *
+ * There are a few things that we do here :
+ * - define a set of parser states (DEFAULT, DIRECTIVE, REFERENCE, etc)
+ * - define for each parser state a set of tokens for each state
+ * - define the VTL grammar, expressed (mostly) in the productions such as
Text(), SetStatement(), etc.
+ *
+ * (cont)
+ */
+
options
{
/** The default package for this parser kit */
@@ -122,7 +141,7 @@
*
* @author <a href="mailto:[EMAIL PROTECTED]">Jason van Zyl</a>
* @author <a href="mailto:[EMAIL PROTECTED]">Geir Magnusson Jr.</a>
- * @version $Id: Parser.jjt,v 1.12 2000/11/01 01:10:34 geirm Exp $
+ * @version $Id: Parser.jjt,v 1.13 2000/11/01 23:13:00 geirm Exp $
*/
public class Parser
{
