Merge pull request johnhungerford#3 from getkyo/main

Add `.unless` extension

zikyo-core/shared/src/main/scala/zikyo/package.scala

@@ -80,11 +80,8 @@ package object zikyo:
         def fromAutoCloseable[A <: AutoCloseable, S](closeable: => A < S): A < (S & Resources) =
             acquireRelease(closeable)(c => IOs(c.close()))
 
-        def fromEither[E, A](either: Either[E, A])(using Tag[Aborts[E]]): A < (Aborts[E]) =
-            val aborts = Aborts[E]
-            println("HI")
-            aborts.get(either)
-        end fromEither
+        def fromEither[E, A](either: Either[E, A])(using Tag[Aborts[E]]): A < Aborts[E] =
+            Aborts[E].get(either)
 
         def fromFuture[A: Flat, S](future: => Future[A] < S): A < (S & Fibers) =
             future.map(f => Fibers.fromFuture(f))
@@ -341,6 +338,9 @@ package object zikyo:
         def tap[S1](f: A => Any < S1): A < (S & S1) =
             effect.map(a => f(a).as(a))
 
+        def unless[S1](condition: Boolean < S1): A < (S & S1 & Options) =
+            condition.map(c => if c then Options.empty else effect)
+
     end extension
 
     extension [A, S, E](effect: A < (S & Aborts[E]))

zikyo-core/shared/src/test/scala/zikyoTest/effectsTest.scala

@@ -70,6 +70,22 @@ class effectsTest extends ZiKyoTest:
             assert(handledEffectWhen2.pure == Some(false))
         }
 
+        "unless" in {
+            val effect = IOs("value").unless(Envs[Boolean].get)
+
+            def runEffect(b: Boolean) =
+                IOs.run {
+                    Envs[Boolean].run(b) {
+                        Options.run {
+                            effect
+                        }
+                    }
+                }.pure
+
+            assert(runEffect(true) == None)
+            assert(runEffect(false) == Some("value"))
+        }
+
         "tap" in {
             val effect: Int < IOs = IOs(42).tap(v => assert(42 == v))
             val handled           = IOs.run(effect)