diff --git a/parse.py b/parse.py
index 0f11950..0847b21 100644
--- a/parse.py
+++ b/parse.py
@@ -150,14 +150,14 @@
         log.log(log.PARSER, log.DEBUG, "Parsed language version %s" % (version))
         return version
 
-    def parse_value(self, type, value):
+    def parse_value(self, context, subject, type, value):
+        context = ParseContext(context, "parsing %s value" % (subject))
         if type == "symbol":
             return Reference(value)
         elif type == "text":
             return Text(value)
         else:
-            log.log(log.PARSER, log.NORMAL, "Unexpected type %s" % (type))
-            return None
+            raise ParseError(context, "Unexpected value type '%s'" % (type))
 
     def parse_arguments(self, context, terminator):
         context = ParseContext(context, "parsing arguments until '%s'" % (terminator))
@@ -170,20 +170,14 @@
                 else:
                     raise ParseError(context, "Unexpected keyword '%s' in arguments" % (token.value))
             else:
-                arg = self.parse_value(token.type, token.value)
-                if not arg:
-                    log.log(log.PARSER, log.NORMAL, "While parsing argument")
-                    return None
+                arg = self.parse_value(context, "argument", token.type, token.value)
                 log.log(log.PARSER, log.TRACE, "Parsed %s" % (arg))
                 args.append(arg)
 
     def parse_statement(self, context, terminator, type):
         context = ParseContext(context, "parsing %s statement" % (type))
         token = self.next()
-        subject = self.parse_value(token.type, token.value)
-        if not subject:
-            log.log(log.PARSER, log.NORMAL, "While parsing subject")
-            return None
+        subject = self.parse_value(context, "subject", token.type, token.value)
         token = self.next()
         if token.type == "keyword":
             if token.value == terminator: