[tracker/parser] SPARQL: Support unary minus

[Jürg Billeter <juergbi src gnome org>]

commit 1a7aed5279c7ec512c27b5b207517fdc8039d06f
Author: Jürg Billeter <j bitron ch>
Date:   Wed Aug 12 13:02:45 2009 +0200

    SPARQL: Support unary minus

 src/libtracker-data/tracker-sparql-query.vala |    8 ++++++++
 1 files changed, 8 insertions(+), 0 deletions(-)
---
diff --git a/src/libtracker-data/tracker-sparql-query.vala b/src/libtracker-data/tracker-sparql-query.vala
index c610e1f..9f093ba 100644
--- a/src/libtracker-data/tracker-sparql-query.vala
+++ b/src/libtracker-data/tracker-sparql-query.vala
@@ -1214,6 +1214,14 @@ public class Tracker.SparqlQuery : Object {
 			translate_primary_expression (sql);
 			sql.append (")");
 			return;
+		} else if (accept (SparqlTokenType.PLUS)) {
+			translate_primary_expression (sql);
+			return;
+		} else if (accept (SparqlTokenType.MINUS)) {
+			sql.append ("-(");
+			translate_primary_expression (sql);
+			sql.append (")");
+			return;
 		}
 		translate_primary_expression (sql);
 	}