From 9450d86881a92c402d6e947ee09a70b6ec619ecd Mon Sep 17 00:00:00 2001
From: Barak Michener <me@barakmich.com>
Date: Thu, 5 Feb 2015 21:13:30 -0500
Subject: [PATCH 1/2] bench: Add some grunty Not queries to the integration
 test (derived from existing queries)

---
 cayley_test.go | 53 ++++++++++++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 48 insertions(+), 5 deletions(-)

diff --git a/cayley_test.go b/cayley_test.go
index 75ebd00..53e555b 100644
--- a/cayley_test.go
+++ b/cayley_test.go
@@ -127,6 +127,41 @@ var benchmarkQueries = []struct {
 		},
 	},
 
+	// Exercises Not().Contains(), as above.
+	{
+		message: "the helpless checker, negated (films without Ingrid Bergman)",
+		long:    true,
+		query: `
+			g.V().As("person").In("name").In().In().Out("name").Except(g.V("Ingrid Bergman").In("name").In().In().Out("name")).Is("Casablanca").All()
+			`,
+		tag:    "person",
+		expect: [][]interface{}{},
+	},
+	{
+		message: "the helpless checker, negated (without actors Ingrid Bergman)",
+		long:    true,
+		query: `
+			g.V().As("person").In("name").Except(g.V("Ingrid Bergman").In("name")).In().In().Out("name").Is("Casablanca").All()
+			`,
+		tag: "person",
+		expect: [][]interface{}{
+			{map[string]string{"id": "Casablanca", "person": "Madeleine LeBeau"}},
+			{map[string]string{"id": "Casablanca", "person": "Joy Page"}},
+			{map[string]string{"id": "Casablanca", "person": "Claude Rains"}},
+			{map[string]string{"id": "Casablanca", "person": "S.Z. Sakall"}},
+			{map[string]string{"id": "Casablanca", "person": "Helmut Dantine"}},
+			{map[string]string{"id": "Casablanca", "person": "Conrad Veidt"}},
+			{map[string]string{"id": "Casablanca", "person": "Paul Henreid"}},
+			{map[string]string{"id": "Casablanca", "person": "Peter Lorre"}},
+			{map[string]string{"id": "Casablanca", "person": "Sydney Greenstreet"}},
+			{map[string]string{"id": "Casablanca", "person": "Leonid Kinskey"}},
+			{map[string]string{"id": "Casablanca", "person": "Lou Marcelle"}},
+			{map[string]string{"id": "Casablanca", "person": "Dooley Wilson"}},
+			{map[string]string{"id": "Casablanca", "person": "John Qualen"}},
+			{map[string]string{"id": "Casablanca", "person": "Humphrey Bogart"}},
+		},
+	},
+
 	//Q: Who starred in both "The Net" and "Speed" ?
 	//A: "Sandra Bullock"
 	{
@@ -585,26 +620,34 @@ func BenchmarkHelplessContainsChecker(b *testing.B) {
 	runBench(3, b)
 }
 
-func BenchmarkNetAndSpeed(b *testing.B) {
+func BenchmarkHelplessNotContainsFilms(b *testing.B) {
 	runBench(4, b)
 }
 
-func BenchmarkKeanuAndNet(b *testing.B) {
+func BenchmarkHelplessNotContainsActors(b *testing.B) {
 	runBench(5, b)
 }
 
-func BenchmarkKeanuAndSpeed(b *testing.B) {
+func BenchmarkNetAndSpeed(b *testing.B) {
 	runBench(6, b)
 }
 
-func BenchmarkKeanuOther(b *testing.B) {
+func BenchmarkKeanuAndNet(b *testing.B) {
 	runBench(7, b)
 }
 
-func BenchmarkKeanuBullockOther(b *testing.B) {
+func BenchmarkKeanuAndSpeed(b *testing.B) {
 	runBench(8, b)
 }
 
+func BenchmarkKeanuOther(b *testing.B) {
+	runBench(9, b)
+}
+
+func BenchmarkKeanuBullockOther(b *testing.B) {
+	runBench(10, b)
+}
+
 // reader is a test helper to filter non-io.Reader methods from the contained io.Reader.
 type reader struct {
 	r io.Reader

From cd35572b6c1703e9c6ffb25501fc51fd1a910a86 Mon Sep 17 00:00:00 2001
From: Barak Michener <me@barakmich.com>
Date: Thu, 5 Feb 2015 21:30:43 -0500
Subject: [PATCH 2/2] Update the docs, fixes #205

---
 docs/GremlinAPI.md | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/docs/GremlinAPI.md b/docs/GremlinAPI.md
index 5048f6e..144b425 100644
--- a/docs/GremlinAPI.md
+++ b/docs/GremlinAPI.md
@@ -289,6 +289,27 @@ var dFollows = g.V("D").Out("follows")
 // People followed by both C (B and D) and D (B and G) -- returns B (from C), B (from D), D and G.
 cFollows.Union(dFollows)
 ```
+####**`path.Except(query)`**
+
+Alias: `path.Difference`
+
+Arguments:
+
+  * `query`: Another query path, the result sets of which will be intersected and negated
+
+Removes all paths which match `query` from `path`.
+
+In a set-theoretic sense, this is (A - B). While `g.V().Except(path)` to achieve `U - B = !B` is supported, it's often very slow.
+
+Example:
+```javascript
+var cFollows = g.V("C").Out("follows")
+var dFollows = g.V("D").Out("follows")
+// People followed by both C (B and D) and D (B and G) -- returns B.
+cFollows.Except(dFollows)   // The set (D) -- what C follows that D does not also follow.
+// Equivalently, g.V("C").Out("follows").Except(g.V("D").Out("follows"))
+```
+
 
 ### Using Morphisms