antijoin bug v2

Author: frankmcsherry

README.md

@@ -25,11 +25,11 @@ fn main() {
 
     // .. and then start iterating rules!
     while iteration.changed() {
-        // nodes(a,c) <-  nodes(a,b), edges(b,c)
+        // nodes(a,c)  <-  nodes(a,b), edges(b,c)
         nodes_var.from_join(&nodes_var, &edges_var, |_b, &a, &c| (c,a));
     }
 
-    // extract a `Vec<(u32,u32)>` containing the final results.
-    let reachable = variable.complete();
+    // extract the final results.
+    let reachable: Vec<(u32,u32)> = variable.complete();
 }
 ```

src/join.rs

@@ -43,9 +43,7 @@ pub fn antijoin_into<Key: Ord, Val: Ord, Result: Ord, F: Fn(&Key, &Val)->Result>
         }
     }
 
-    // elements should be in-order, as just a filter.
-    let relation = Relation { elements: results };
-    output.insert(relation);
+    output.insert(results.into());
 }
 
 fn join_helper<K: Ord, V1, V2, F: FnMut(&K, &V1, &V2)>(mut slice1: &[(K,V1)], mut slice2: &[(K,V2)], mut result: F) {
@@ -54,12 +52,12 @@ fn join_helper<K: Ord, V1, V2, F: FnMut(&K, &V1, &V2)>(mut slice1: &[(K,V1)], mu
 
         if slice1[0].0 == slice2[0].0 {
 
-            let mut key1_count = 0;
+            let mut key1_count = 1;
             while key1_count < slice1.len() && slice1[0].0 == slice1[key1_count].0 {
                 key1_count += 1;
             }
 
-            let mut key2_count = 0;
+            let mut key2_count = 1;
             while key2_count < slice2.len() && slice2[0].0 == slice2[key2_count].0 {
                 key2_count += 1;
             }

src/lib.rs

@@ -149,7 +149,7 @@ impl<Tuple: Ord> Variable<Tuple> {
     /// pairs are symmetric, this should result in all pairs (x, y) for x and y in 0 .. 11.
     ///
     /// ```
-    /// use datafrog::*;
+    /// use datafrog::{Iteration, Relation};
     ///
     /// let mut iteration = Iteration::new();
     /// let variable = iteration.variable::<(usize, usize)>("source");
@@ -180,7 +180,7 @@ impl<Tuple: Ord> Variable<Tuple> {
     /// pairs (for 0, 3, 6, and 9) which should leave us with 16 total pairs.
     ///
     /// ```
-    /// use datafrog::*;
+    /// use datafrog::{Iteration, Relation};
     ///
     /// let mut iteration = Iteration::new();
     /// let variable = iteration.variable::<(usize, usize)>("source");
@@ -213,7 +213,7 @@ impl<Tuple: Ord> Variable<Tuple> {
     /// pairs (x, y) where x visits y as part of its Collatz journey.
     ///
     /// ```
-    /// use datafrog::*;
+    /// use datafrog::{Iteration, Relation};
     ///
     /// let mut iteration = Iteration::new();
     /// let variable = iteration.variable::<(usize, usize)>("source");
@@ -294,7 +294,9 @@ impl<Tuple: Ord> VariableTrait for Variable<Tuple> {
             let last = self.tuples.borrow_mut().pop().unwrap();
             recent = recent.merge(last);
         }
-        self.tuples.borrow_mut().push(recent);
+        if !recent.is_empty() {
+            self.tuples.borrow_mut().push(recent);
+        }
 
         // 2. Move self.to_add into self.recent.
         let to_add = self.to_add.borrow_mut().pop();