extend result error samples

src/func/instances/result.rs

@@ -250,7 +250,7 @@ impl<'a, T: Monad<'a>> MonadFailAny<'a> for ResultFailOver<T> {
 mod result_tests {
     use super::{test_suite, tests, ResultInstance};
 
-    type T = ResultInstance<bool>;
+    type T = ResultInstance<i32>;
 
     impl<'a> tests::Eqr<'a> for T {
         fn eqr<A: 'a + Send + PartialEq + std::fmt::Debug>(
@@ -264,8 +264,10 @@ mod result_tests {
 
     impl<'a> test_suite::FunctorTestSuite<'a> for T {
         fn sample<A: 'a + Send, F: FnMut(&'a (dyn Send + Sync + Fn(A) -> Self::F<A>))>(mut f: F) {
-            f(&|_| Err(false));
-            f(&|_| Err(true));
+            f(&|_| Err(0));
+            f(&|_| Err(1));
+            f(&|_| Err(2));
+            f(&|_| Err(3));
             f(&|a| Ok(a));
         }
     }