[PATCH] Allow lone "not" search operators

[Adrian Perez <aperez@igalia.com>]

As suggested by Keith in FLAG_PURE_NOT allows for expressions like:

  notmuch search NOT tag:inbox

Note that this way a search like:

  notmuch search foobar NOT tag:inbox

should not be written instead:

  notmuch search foobar AND NOT tag:inbox

In my opinion, the latter feels more natural and is somewhat more explicit.
It gives a better clue of what the search is about instead of assuming that
an implicit AND operator is there.

---
 lib/query.cc |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/lib/query.cc b/lib/query.cc
index a869f3e..75f22b3 100644
--- a/lib/query.cc
+++ b/lib/query.cc
@@ -97,7 +97,8 @@ notmuch_query_search_messages (notmuch_query_t *query,
 			      Xapian::QueryParser::FLAG_PHRASE |
 			      Xapian::QueryParser::FLAG_LOVEHATE |
 			      Xapian::QueryParser::FLAG_BOOLEAN_ANY_CASE |
-			      Xapian::QueryParser::FLAG_WILDCARD);
+			      Xapian::QueryParser::FLAG_WILDCARD |
+			      Xapian::QueryParser::FLAG_PURE_NOT);
 
 	if (strcmp (query_string, "") == 0) {
 	    final_query = mail_query;
-- 
1.6.5.2