# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1481416653 -3600
# Node ID ff3ebfe09afc76e3002252684ec1b3822642cb43
# Parent  01ac965a92a9c153dad924f30cf4e99161b7f43d
Produce an error when an argument is not supported by any known parameter.

diff -r 01ac965a92a9 -r ff3ebfe09afc translator.py
--- a/translator.py	Sat Dec 10 22:02:51 2016 +0100
+++ b/translator.py	Sun Dec 11 01:37:33 2016 +0100
@@ -1140,7 +1140,11 @@
                 # argument directly.
 
                 if parameters:
-                    argnum = parameters.index(arg.name)
+                    try:
+                        argnum = parameters.index(arg.name)
+                    except ValueError:
+                        raise TranslateError("Argument %s is not recognised." % arg.name,
+                                             self.get_namespace_path(), n)
                     args[argnum+1] = str(argexpr)
 
                 # Otherwise, store the details in a separate collection.