Implement functional notation for reply actions

* NEWS, doc/mailfromd.texi: Update.
* mfd/drivers.c (print_type_result, mark_type_result)
(optimize_type_result, code_type_result): Rewrite.
* mfd/gram.y: Rewrite action rules.
* mfd/lex.l (CODE,XCODE): Remove.
* mfd/opcodes (RESULT): Takes one immediate parameter.
(instr_result): Get arguments from stack.

1 files changed, 18 insertions, 1 deletions

diff --git a/NEWS b/NEWS
index b50d87a8..90b7a889 100644
--- a/NEWS
+++ b/NEWS
@@ -1,4 +1,4 @@
-Mailfromd NEWS -- history of user-visible changes. 2009-05-10
+Mailfromd NEWS -- history of user-visible changes. 2009-05-11
 Copyright (C) 2005, 2006, 2007, 2008, 2009 Sergey Poznyakoff
 See the end of file for copying conditions.
 
@@ -24,6 +24,23 @@ is not strictly necessary.  However, keep in mind that due to the
 specifics of MeTA1, the number of symbols that may be exported for
 each stage is limited (Mailfromd manual, section 11.1.2).
 
+* Reject and tempfail actions: Functional notation
+
+The reply actions `reject' and `tempfail' allow functional notation,
+i.e. their arguments can be supplied as to a function:
+
+  reject(550, 5.7.7, "IP address does not resolve")
+
+An important feature of this notation is that all three arguments are
+MFL expressions, which means that you can now compute the reply codes
+at run time:
+
+  reject(550 + %n, "5.7." %x, "Transaction rejected")
+
+An argument can be omitted, in which case the default value is used, e.g.:
+
+  reject(550 + %n, , "Transaction rejected")
+  
 * New functions
 
 A set of new functions is added that allow to access the headers