From f8d8a77b1fa8ddf45fa762e35d6d347a1361a868 Mon Sep 17 00:00:00 2001
From: timofey <tim@ongoteam.yaconnect.com>
Date: Sun, 15 Oct 2023 14:26:40 +0000
Subject: [PATCH] void_can_be_exressed_via_replace

---
 src/func/test_suite.rs |  3 +++
 src/func/tests.rs      | 14 ++++++++++++++
 2 files changed, 17 insertions(+)

diff --git a/src/func/test_suite.rs b/src/func/test_suite.rs
index 93eaeee..86d4f08 100644
--- a/src/func/test_suite.rs
+++ b/src/func/test_suite.rs
@@ -75,5 +75,8 @@ pub fn monad_follows_laws<'a, T: Monad<'a> + FunctorTestSuite<'a>>() -> R {
     T::sample(|pa| {
         res += fmap_can_be_expressed_via_bind::<T, _, _>(|x| x + 3, || pa(2));
     });
+    T::sample(|pa| {
+        res += void_can_be_exressed_via_replace::<T, _>(|| pa(2));
+    });
     res
 }
diff --git a/src/func/tests.rs b/src/func/tests.rs
index 185dfac..66d57ba 100644
--- a/src/func/tests.rs
+++ b/src/func/tests.rs
@@ -317,3 +317,17 @@ pub fn fmap_can_be_expressed_via_bind<
         T::bind(fa0(), move |a| T::pure(f(a))),
     )
 }
+
+pub fn void_can_be_exressed_via_replace<
+    'a,
+    T: Monad<'a> + Eqr<'a>,
+    A: 'a + Send + Debug + PartialEq,
+>(
+    fa0: impl Fn() -> T::F<A>,
+) -> R {
+    T::eqr(
+        "void via bind: void x  =  () <$ x",
+        T::void(fa0()),
+        T::replace(fa0(), ()),
+    )
+}