test stackless iteration

src/func/instances/stackless.rs

@@ -262,6 +262,8 @@ impl<'a> Monad<'a> for StacklessInstance {
 
 #[cfg(test)]
 mod stackless_test {
+    use crate::func::*;
+
     use super::{test_suite, tests, Stackless};
 
     use super::StacklessInstance as T;
@@ -303,6 +305,17 @@ mod stackless_test {
         }
     }
 
+    fn iterate(n: u32) -> Stackless<'static, u32> {
+        T::iterate_mut((n, 0), |(a, b)| {
+            if a > 0 {
+                ControlFlow::Continue((a - 1, b + 1))
+            } else {
+                ControlFlow::Break(b)
+            }
+            .into()
+        })
+    }
+
     #[test]
     fn test_factorial() {
         assert_eq!(factorial(10).evaluate(), 3628800);
@@ -313,4 +326,10 @@ mod stackless_test {
         let n = 1000;
         assert_eq!(dumb(n).evaluate(), n);
     }
+
+    #[test]
+    fn test_iterate() {
+        let n = 1000;
+        assert_eq!(iterate(n).evaluate(), n);
+    }
 }