> inverted() {
/**
* A lens that focuses on a map while mapping its values with the mapping {@link Iso}.
*
- * Note that for this lens to be lawful, iso must be bijective: that is, every V must
- * uniquely and invertibly map to exactly one V2.
+ * Note that for this lens to be lawful, iso must be lawful.
*
* @param iso the mapping {@link Iso}
* @param the key type
diff --git a/src/main/java/com/jnape/palatable/lambda/monad/Monad.java b/src/main/java/com/jnape/palatable/lambda/monad/Monad.java
index 11b18d84c..4c3e2e18d 100644
--- a/src/main/java/com/jnape/palatable/lambda/monad/Monad.java
+++ b/src/main/java/com/jnape/palatable/lambda/monad/Monad.java
@@ -1,9 +1,12 @@
package com.jnape.palatable.lambda.monad;
+import com.jnape.palatable.lambda.functions.builtin.fn1.Id;
import com.jnape.palatable.lambda.functor.Applicative;
import java.util.function.Function;
+import static com.jnape.palatable.lambda.functions.builtin.fn1.Id.id;
+
/**
* Monads are {@link Applicative} functors that support a flattening operation to unwrap M<M<A>>
* -> M<A>. This flattening operation, coupled with {@link Applicative#zip(Applicative)}, gives rise to
@@ -53,7 +56,7 @@ default Monad fmap(Function fn) {
*/
@Override
default Monad zip(Applicative, M> appFn) {
- return appFn., M>>coerce().flatMap(ab -> fmap(ab::apply));
+ return appFn., M>>coerce().flatMap(this::fmap);
}
/**
@@ -71,4 +74,17 @@ default Monad discardL(Applicative appB) {
default Monad discardR(Applicative appB) {
return Applicative.super.discardR(appB).coerce();
}
+
+ /**
+ * Convenience static method equivalent to {@link Monad#flatMap(Function) flatMap}{@link Id#id() (id())};
+ *
+ * @param mma the outer monad
+ * @param the monad type
+ * @param the nested type parameter
+ * @param the nested monad
+ * @return the nested monad
+ */
+ static > MA join(Monad mma) {
+ return mma.flatMap(id()).coerce();
+ }
}
\ No newline at end of file
diff --git a/src/main/java/com/jnape/palatable/lambda/monoid/builtin/MergeMaps.java b/src/main/java/com/jnape/palatable/lambda/monoid/builtin/MergeMaps.java
new file mode 100644
index 000000000..104d6f7d5
--- /dev/null
+++ b/src/main/java/com/jnape/palatable/lambda/monoid/builtin/MergeMaps.java
@@ -0,0 +1,61 @@
+package com.jnape.palatable.lambda.monoid.builtin;
+
+import com.jnape.palatable.lambda.functions.Fn1;
+import com.jnape.palatable.lambda.functions.specialized.BiMonoidFactory;
+import com.jnape.palatable.lambda.functions.specialized.MonoidFactory;
+import com.jnape.palatable.lambda.monoid.Monoid;
+import com.jnape.palatable.lambda.semigroup.Semigroup;
+
+import java.util.Map;
+import java.util.function.BiFunction;
+import java.util.function.Supplier;
+
+/**
+ * A {@link Monoid} instance formed by {@link java.util.Map#merge(Object, Object, BiFunction)} and a semigroup over
+ * V. Combines together multiple maps using the provided semigroup for key collisions.
+ *
+ * @param The key parameter type of the Map
+ * @param The value parameter type of the Map
+ * @see Monoid
+ * @see java.util.Map
+ */
+public final class MergeMaps implements BiMonoidFactory>, Semigroup, Map> {
+
+ private static final MergeMaps INSTANCE = new MergeMaps();
+
+ private MergeMaps() {
+ }
+
+ @Override
+ public Monoid> apply(Supplier> mSupplier, Semigroup semigroup) {
+ return Monoid.>monoid((x, y) -> {
+ Map copy = mSupplier.get();
+ copy.putAll(x);
+ y.forEach((k, v) -> copy.merge(k, v, semigroup.toBiFunction()));
+ return copy;
+ }, mSupplier);
+ }
+
+ @SuppressWarnings("unchecked")
+ public static MergeMaps mergeMaps() {
+ return INSTANCE;
+ }
+
+ public static MonoidFactory, Map> mergeMaps(Supplier> mSupplier) {
+ return MergeMaps.mergeMaps().apply(mSupplier);
+ }
+
+ public static Monoid> mergeMaps(Supplier> mSupplier, Semigroup semigroup) {
+ return mergeMaps(mSupplier).apply(semigroup);
+ }
+
+ public static Fn1, Map> mergeMaps(Supplier> mSupplier, Semigroup semigroup,
+ Map x) {
+ return mergeMaps(mSupplier, semigroup).apply(x);
+ }
+
+ public static Map mergeMaps(Supplier> mSupplier, Semigroup semigroup, Map x,
+ Map y) {
+ return mergeMaps(mSupplier, semigroup, x).apply(y);
+ }
+}
diff --git a/src/main/java/com/jnape/palatable/lambda/semigroup/builtin/AddAll.java b/src/main/java/com/jnape/palatable/lambda/semigroup/builtin/AddAll.java
deleted file mode 100644
index fe22ba5c2..000000000
--- a/src/main/java/com/jnape/palatable/lambda/semigroup/builtin/AddAll.java
+++ /dev/null
@@ -1,44 +0,0 @@
-package com.jnape.palatable.lambda.semigroup.builtin;
-
-import com.jnape.palatable.lambda.functions.Fn1;
-import com.jnape.palatable.lambda.monoid.Monoid;
-import com.jnape.palatable.lambda.semigroup.Semigroup;
-
-import java.util.Collection;
-
-/**
- * The {@link Semigroup} instance formed under mutative concatenation for an arbitrary {@link Collection}. The
- * collection subtype (C) must support {@link Collection#addAll(Collection)}.
- *
- * For the {@link Monoid}, see {@link com.jnape.palatable.lambda.monoid.builtin.AddAll}.
- *
- * @see Semigroup
- * @deprecated in favor of the now non-modifying {@link com.jnape.palatable.lambda.monoid.builtin.AddAll monoid}
- */
-@Deprecated
-public final class AddAll> implements Semigroup {
-
- private static final AddAll INSTANCE = new AddAll();
-
- private AddAll() {
- }
-
- @Override
- public C apply(C xs, C ys) {
- xs.addAll(ys);
- return xs;
- }
-
- @SuppressWarnings("unchecked")
- public static > AddAll addAll() {
- return INSTANCE;
- }
-
- public static > Fn1 addAll(C xs) {
- return AddAll.addAll().apply(xs);
- }
-
- public static > C addAll(C xs, C ys) {
- return addAll(xs).apply(ys);
- }
-}
diff --git a/src/test/java/com/jnape/palatable/lambda/functions/EffectTest.java b/src/test/java/com/jnape/palatable/lambda/functions/EffectTest.java
index 1b22b349b..9f5dabd60 100644
--- a/src/test/java/com/jnape/palatable/lambda/functions/EffectTest.java
+++ b/src/test/java/com/jnape/palatable/lambda/functions/EffectTest.java
@@ -1,22 +1,51 @@
package com.jnape.palatable.lambda.functions;
+import com.jnape.palatable.lambda.adt.Unit;
import org.junit.Test;
-import java.util.function.Consumer;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.concurrent.atomic.AtomicInteger;
+import static com.jnape.palatable.lambda.adt.Unit.UNIT;
+import static com.jnape.palatable.lambda.functions.Effect.effect;
import static com.jnape.palatable.lambda.functions.builtin.fn1.Constantly.constantly;
-import static com.jnape.palatable.lambda.functions.specialized.Noop.noop;
+import static java.util.Arrays.asList;
+import static org.junit.Assert.assertEquals;
public class EffectTest {
@Test
- @SuppressWarnings("unused")
public void covariantReturns() {
- Effect effect = noop();
- Effect