Panic instead of partially running actions (#234)

* Panic instead of ignoring errors in EGraph::step_rules

* Fix semi_naive_set_function test by moving lookup into query

* Fix herbie-tutorial test

* Add explicit panic message

src/lib.rs

@@ -840,15 +840,15 @@ impl EGraph {
             // run one iteration when n == 0
             if num_vars == 0 {
                 rule.matches += 1;
-                // we can ignore results here
                 stack.clear();
-                let _ = self.run_actions(stack, &[], &rule.program, true);
+                self.run_actions(stack, &[], &rule.program, true)
+                    .unwrap_or_else(|e| panic!("error while running actions for {name}: {e}"));
             } else {
                 for values in all_values.chunks(num_vars) {
                     rule.matches += 1;
-                    // we can ignore results here
                     stack.clear();
-                    let _ = self.run_actions(stack, values, &rule.program, true);
+                    self.run_actions(stack, values, &rule.program, true)
+                        .unwrap_or_else(|e| panic!("error while running actions for {name}: {e}"));
                 }
             }
 

tests/herbie-tutorial.egg

@@ -41,12 +41,10 @@
 (rule ((Num r))
       ((set (lower-bound (Num r)) r)
        (set (upper-bound (Num r)) r)))
-(rule ((= e (Add a b)))
-      ((set (lower-bound e)
-            (+ (lower-bound a) (lower-bound b)))))
-(rule ((= e (Add a b)))
-      ((set (upper-bound e)
-            (+ (upper-bound a) (upper-bound b)))))
+(rule ((= e (Add a b)) (= x (lower-bound a)) (= y (lower-bound b)))
+      ((set (lower-bound e) (+ x y))))
+(rule ((= e (Add a b)) (= x (upper-bound a)) (= y (upper-bound b)))
+      ((set (upper-bound e) (+ x y))))
 (rule ((= e (Mul a b)))
       ((set (lower-bound e)
             (min (* (lower-bound a) (lower-bound b))

tests/semi_naive_set_function.egg

@@ -96,7 +96,7 @@
 (function g (i64) i64 :merge (max old new))
 (set (g 0) 0)
 (set (g 1) 1)
-(rule ((= x (g x))) ((set (g (+ x 1)) (+ (g (- x 1)) 2))))
+(rule ((= x (g x)) (= y (g (- x 1)))) ((set (g (+ x 1)) (+ y 2))))
 
 (run 100)
 (print-table g)