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IterateT, ListT done right (https://wiki.haskell.org/ListT_done_right)
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‎CHANGELOG.md

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@@ -15,6 +15,7 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/).
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- `MaybeT#or`, choose the first `MaybeT` that represents an effect around `just` a value
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- `StateMatcher, StateTMatcher, WriterTMatcher`
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- `ReaderT#and`, category composition between `ReaderT` instances: `(a -> m b) -> (b -> m c) -> (a -> m c)`
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- `IterateT`, [`ListT` done right](https://wiki.haskell.org/ListT_done_right)
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## [5.1.0] - 2019-10-13
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### Changed

‎src/main/java/com/jnape/palatable/lambda/internal/iteration/ImmutableQueue.java renamed to ‎src/main/java/com/jnape/palatable/lambda/internal/ImmutableQueue.java

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package com.jnape.palatable.lambda.internal.iteration;
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package com.jnape.palatable.lambda.internal;
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import com.jnape.palatable.lambda.adt.Maybe;
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import static com.jnape.palatable.lambda.functions.builtin.fn1.Constantly.constantly;
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import static com.jnape.palatable.lambda.functions.builtin.fn3.FoldLeft.foldLeft;
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abstract class ImmutableQueue<A> implements Iterable<A> {
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/**
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* Internal API. Use at your own peril.
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*/
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public abstract class ImmutableQueue<A> implements Iterable<A> {
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abstract ImmutableQueue<A> pushFront(A a);
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public abstract ImmutableQueue<A> pushFront(A a);
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abstract ImmutableQueue<A> pushBack(A a);
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public abstract ImmutableQueue<A> pushBack(A a);
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abstract Maybe<A> head();
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public abstract Maybe<A> head();
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abstract ImmutableQueue<A> tail();
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public abstract ImmutableQueue<A> tail();
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abstract ImmutableQueue<A> concat(ImmutableQueue<A> other);
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public abstract ImmutableQueue<A> concat(ImmutableQueue<A> other);
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final boolean isEmpty() {
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public final boolean isEmpty() {
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return head().fmap(constantly(false)).orElse(true);
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}
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public static <A> ImmutableQueue<A> singleton(A a) {
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return new NonEmpty<>(ImmutableStack.<A>empty().push(a), ImmutableStack.empty());
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}
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@Override
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public Iterator<A> iterator() {
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return new Iterator<A>() {
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private static final Empty<?> INSTANCE = new Empty<>();
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@Override
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ImmutableQueue<A> pushFront(A a) {
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public ImmutableQueue<A> pushFront(A a) {
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return new NonEmpty<>(ImmutableStack.<A>empty().push(a), ImmutableStack.empty());
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}
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@Override
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ImmutableQueue<A> pushBack(A a) {
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public ImmutableQueue<A> pushBack(A a) {
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return pushFront(a);
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}
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@Override
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ImmutableQueue<A> concat(ImmutableQueue<A> other) {
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public ImmutableQueue<A> concat(ImmutableQueue<A> other) {
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return other;
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}
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@Override
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Maybe<A> head() {
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public Maybe<A> head() {
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return Maybe.nothing();
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}
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@Override
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ImmutableQueue<A> tail() {
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public ImmutableQueue<A> tail() {
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return this;
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}
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}
@@ -87,27 +94,27 @@ private NonEmpty(ImmutableStack<A> outbound, ImmutableStack<A> inbound) {
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}
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@Override
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ImmutableQueue<A> pushFront(A a) {
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public ImmutableQueue<A> pushFront(A a) {
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return new NonEmpty<>(outbound.push(a), inbound);
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}
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@Override
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ImmutableQueue<A> pushBack(A a) {
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public ImmutableQueue<A> pushBack(A a) {
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return new NonEmpty<>(outbound, inbound.push(a));
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}
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@Override
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ImmutableQueue<A> concat(ImmutableQueue<A> other) {
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public ImmutableQueue<A> concat(ImmutableQueue<A> other) {
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return new NonEmpty<>(outbound, foldLeft(ImmutableStack::push, inbound, other));
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}
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@Override
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Maybe<A> head() {
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public Maybe<A> head() {
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return outbound.head();
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}
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@Override
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ImmutableQueue<A> tail() {
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public ImmutableQueue<A> tail() {
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ImmutableStack<A> outTail = outbound.tail();
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if (!outTail.isEmpty())
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return new NonEmpty<>(outTail, inbound);

‎src/main/java/com/jnape/palatable/lambda/internal/iteration/ImmutableStack.java renamed to ‎src/main/java/com/jnape/palatable/lambda/internal/ImmutableStack.java

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package com.jnape.palatable.lambda.internal.iteration;
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package com.jnape.palatable.lambda.internal;
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import com.jnape.palatable.lambda.adt.Maybe;
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import static com.jnape.palatable.lambda.functions.builtin.fn1.Constantly.constantly;
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abstract class ImmutableStack<A> implements Iterable<A> {
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/**
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* Internal API. Use at your own peril.
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*/
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public abstract class ImmutableStack<A> implements Iterable<A> {
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final ImmutableStack<A> push(A a) {
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public final ImmutableStack<A> push(A a) {
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return new Node<>(a, this);
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}
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abstract Maybe<A> head();
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public abstract Maybe<A> head();
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abstract ImmutableStack<A> tail();
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public abstract ImmutableStack<A> tail();
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final boolean isEmpty() {
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public final boolean isEmpty() {
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return head().fmap(constantly(false)).orElse(true);
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}
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private static final Empty<?> INSTANCE = new Empty<>();
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@Override
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Maybe<A> head() {
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public Maybe<A> head() {
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return Maybe.nothing();
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}
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@Override
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ImmutableStack<A> tail() {
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public ImmutableStack<A> tail() {
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return this;
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}
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}
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}
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@Override
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Maybe<A> head() {
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public Maybe<A> head() {
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return Maybe.just(head);
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}
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@Override
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ImmutableStack<A> tail() {
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public ImmutableStack<A> tail() {
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return tail;
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}
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}

‎src/main/java/com/jnape/palatable/lambda/internal/iteration/ConcatenatingIterable.java

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package com.jnape.palatable.lambda.internal.iteration;
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import com.jnape.palatable.lambda.internal.ImmutableQueue;
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import java.util.Iterator;
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import static com.jnape.palatable.lambda.functions.builtin.fn1.Flatten.flatten;

‎src/main/java/com/jnape/palatable/lambda/internal/iteration/TrampoliningIterator.java

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import com.jnape.palatable.lambda.functions.Fn0;
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import com.jnape.palatable.lambda.functions.Fn1;
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import com.jnape.palatable.lambda.functions.recursion.RecursiveResult;
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import com.jnape.palatable.lambda.internal.ImmutableQueue;
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import java.util.Iterator;
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import java.util.NoSuchElementException;

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