lang/src/main/java/monads/Monad.java

@@ -1,13 +0,0 @@
-package monads;
-
-import java.util.function.Function;
-
-public interface Monad<T> {
-    static <U> Monad<U> unit(U value) {
-        return null;
-    }
-    <U> Monad<U> flatMap(Function<T, Monad<U>> mapper);
-    default <U> Monad<U> map(Function<T, U> mapper) {
-        return flatMap(t -> unit(mapper.apply(t)));
-    }
-}

lang/src/main/java/monads/OptionalExamples.java

@@ -1,69 +0,0 @@
-package monads;
-
-import java.util.Optional;
-
-import static monads.util.OptionalUtils.optionalAdd;
-
-public class OptionalExamples {
-
-    private final Soundcard soundcard;
-    private final Computer computer;
-    private final USB usb;
-
-    public OptionalExamples() {
-        usb = new USB("3.1");
-        soundcard = new Soundcard(usb);
-        computer = new Computer(soundcard);
-    }
-
-    private void nestedOptional() {
-        System.out.println("Nested optionals example");
-        var version = computer.getSoundcard()
-                .flatMap(Soundcard::getUSB)
-                .map(USB::getVersion)
-                .orElse("UNKNOWN");
-        System.out.printf("Version : %s%n", version);
-    }
-
-    private void addOptionals() {
-        System.out.println("Add optionals example");
-        assert optionalAdd(Optional.of(1), Optional.of(1)).equals(Optional.of(2));
-        assert optionalAdd(Optional.of(1), Optional.of(1)).equals(Optional.empty());
-    }
-
-    public static void main(String[] args) {
-        var examples = new OptionalExamples();
-        examples.nestedOptional();
-        examples.addOptionals();
-    }
-
-    private static class Computer {
-        private final Soundcard soundcard;
-
-        private Computer(Soundcard soundcard) {
-            this.soundcard = soundcard;
-        }
-
-        public Optional<Soundcard> getSoundcard() { return Optional.ofNullable(soundcard); }
-    }
-
-    private static class Soundcard {
-        private final USB usb;
-
-        private Soundcard(USB usb) {
-            this.usb = usb;
-        }
-
-        public Optional<USB> getUSB() { return Optional.ofNullable(usb); }
-    }
-
-    private static class USB {
-        private final String version;
-
-        private USB(String version) {
-            this.version = version;
-        }
-
-        public String getVersion(){ return version; }
-    }
-}

lang/src/main/java/monads/ResultExamples.java

@@ -1,37 +0,0 @@
-package monads;
-
-public class ResultExamples {
-    public static void main(String[] args) {
-//        var ok = Result.ok();
-    }
-
-    private static class Result<T> {
-        private final T value;
-        private final String error;
-
-        private Result(T value, String error) {
-            this.value = value;
-            this.error = error;
-        }
-
-        public static <U> Result<U> ok(U value) {
-            return new Result<>(value, null);
-        }
-
-        public static <U> Result<U> error(String error) {
-            return new Result<>(null, error);
-        }
-
-        public boolean isError() {
-            return error != null;
-        }
-
-        public String getError() {
-            return error;
-        }
-
-        public T getValue() {
-            return value;
-        }
-    }
-}

lang/src/main/java/monads/StreamExamples.java

@@ -1,33 +0,0 @@
-package monads;
-
-import java.util.stream.Stream;
-
-public class StreamExamples {
-    /**
-     * Given n > 0 find all pairs (i; j) where
-     * 1 < j <= i <= n and i + j is prime
-     */
-    private Stream<long[]> findPrimes(long n) {
-        return Stream.iterate(1, i -> i + 1)
-                .limit(n)
-                .flatMap(i -> Stream.iterate(1, j -> j + 1)
-                        .limit(n)
-                        .map(j -> new long[] {i, j})
-                ).filter(pair -> isPrime(pair[0] + pair[1]));
-    }
-
-    private boolean isPrime(long n) {
-        return Stream.iterate(2, i -> i + 1)
-                .limit((long) Math.sqrt(n))
-                .noneMatch(i -> n % i == 0);
-    }
-
-    public static void main(String[] args) {
-        StreamExamples examples = new StreamExamples();
-        var start = System.nanoTime();
-        var primes = (Long) examples.findPrimes(10L).count();
-        var end = System.nanoTime();
-        System.out.printf("Elapsed : %fs", (end - start) / 1_000_000_000.0);
-        //primes.map(Arrays::toString).forEach(System.out::println);
-    }
-}

lang/src/main/java/monads/util/OptionalUtils.java

@@ -1,23 +0,0 @@
-package monads.util;
-
-import java.util.Optional;
-import java.util.function.BiFunction;
-
-public final class OptionalUtils {
-    @SuppressWarnings("OptionalUsedAsFieldOrParameterType")
-    public static Optional<Integer> optionalAdd(Optional<Integer> val1, Optional<Integer> val2) {
-        return flatMap2(val1, val2, (first, second) -> Optional.of(first + second));
-    }
-
-    @SuppressWarnings("OptionalUsedAsFieldOrParameterType")
-    public static <T, U, R> Optional<R> flatMap2(
-            Optional<T> opt1,
-            Optional<U> opt2,
-            BiFunction<T, U, Optional<R>> mapper
-    ) {
-        return opt1.flatMap(a ->
-                opt2.flatMap(b ->
-                        mapper.apply(a, b)
-                ));
-    }
-}