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-rw-r--r--base/src/main/java/bjc/utils/data/internals/HalfBoundLazyPair.java177
1 files changed, 0 insertions, 177 deletions
diff --git a/base/src/main/java/bjc/utils/data/internals/HalfBoundLazyPair.java b/base/src/main/java/bjc/utils/data/internals/HalfBoundLazyPair.java
deleted file mode 100644
index 4803bc2..0000000
--- a/base/src/main/java/bjc/utils/data/internals/HalfBoundLazyPair.java
+++ /dev/null
@@ -1,177 +0,0 @@
-package bjc.utils.data.internals;
-
-import java.util.function.BiFunction;
-import java.util.function.Function;
-import java.util.function.Supplier;
-
-import bjc.utils.data.IHolder;
-import bjc.utils.data.IPair;
-import bjc.utils.data.Identity;
-import bjc.utils.data.LazyPair;
-
-/*
- * @NOTE
- * I am not convinced that this code works correctly. Tests should be
- * written to make sure things only ever get instantiated once.
- *
- * Namely, my main concern is to whether the places that bind the pair
- * without setting pairBound are doing the right thing.
- */
-/**
- * A lazy pair, with only one side bound.
- *
- * @author Ben Culkin
- */
-@SuppressWarnings("javadoc")
-public class HalfBoundLazyPair<OldType, NewLeft, NewRight> implements IPair<NewLeft, NewRight> {
- /* The supplier of the old value. */
- private final Supplier<OldType> oldSupplier;
-
- /* The function to transform the old value into a new pair. */
- private final Function<OldType, IPair<NewLeft, NewRight>> binder;
-
- /* The new bound pair. */
- private IPair<NewLeft, NewRight> boundPair;
- /* Has the pair been bound yet or not? */
- private boolean pairBound;
-
- /**
- * Create a new half-bound lazy pair.
- *
- * @param oldSupp
- * The supplier of the old value.
- *
- * @param bindr
- * The function to use to create the pair from the old value.
- */
- public HalfBoundLazyPair(final Supplier<OldType> oldSupp,
- final Function<OldType, IPair<NewLeft, NewRight>> bindr) {
- oldSupplier = oldSupp;
- binder = bindr;
- }
-
- @Override
- public <BoundLeft, BoundRight> IPair<BoundLeft, BoundRight> bind(
- final BiFunction<NewLeft, NewRight, IPair<BoundLeft, BoundRight>> bindr) {
- final IHolder<IPair<NewLeft, NewRight>> newPair = new Identity<>(boundPair);
- final IHolder<Boolean> newPairMade = new Identity<>(pairBound);
-
- final Supplier<NewLeft> leftSupp = () -> {
- if(!newPairMade.getValue()) {
- /* Bind the pair if it hasn't been bound yet. */
- newPair.replace(binder.apply(oldSupplier.get()));
- newPairMade.replace(true);
- }
-
- return newPair.unwrap((pair) -> pair.getLeft());
- };
-
- final Supplier<NewRight> rightSupp = () -> {
- if(!newPairMade.getValue()) {
- /* Bind the pair if it hasn't been bound yet. */
- newPair.replace(binder.apply(oldSupplier.get()));
- newPairMade.replace(true);
- }
-
- return newPair.unwrap((pair) -> pair.getRight());
- };
-
- return new BoundLazyPair<>(leftSupp, rightSupp, bindr);
- }
-
- @Override
- public <BoundLeft> IPair<BoundLeft, NewRight> bindLeft(
- final Function<NewLeft, IPair<BoundLeft, NewRight>> leftBinder) {
- final Supplier<NewLeft> leftSupp = () -> {
- IPair<NewLeft, NewRight> newPair = boundPair;
-
- if(!pairBound) {
- newPair = binder.apply(oldSupplier.get());
- }
-
- return newPair.getLeft();
- };
-
- return new HalfBoundLazyPair<>(leftSupp, leftBinder);
- }
-
- @Override
- public <BoundRight> IPair<NewLeft, BoundRight> bindRight(
- final Function<NewRight, IPair<NewLeft, BoundRight>> rightBinder) {
- final Supplier<NewRight> rightSupp = () -> {
- IPair<NewLeft, NewRight> newPair = boundPair;
-
- if(!pairBound) {
- newPair = binder.apply(oldSupplier.get());
- }
-
- return newPair.getRight();
- };
-
- return new HalfBoundLazyPair<>(rightSupp, rightBinder);
- }
-
- @Override
- public <OtherLeft, OtherRight, CombinedLeft, CombinedRight> IPair<CombinedLeft, CombinedRight> combine(
- final IPair<OtherLeft, OtherRight> otherPair,
- final BiFunction<NewLeft, OtherLeft, CombinedLeft> leftCombiner,
- final BiFunction<NewRight, OtherRight, CombinedRight> rightCombiner) {
- return otherPair.bind((otherLeft, otherRight) -> {
- return bind((leftVal, rightVal) -> {
- CombinedLeft cLeft = leftCombiner.apply(leftVal, otherLeft);
- CombinedRight cRight = rightCombiner.apply(rightVal, otherRight);
-
- return new LazyPair<>(cLeft, cRight);
- });
- });
- }
-
- @Override
- public <NewLeftType> IPair<NewLeftType, NewRight> mapLeft(final Function<NewLeft, NewLeftType> mapper) {
- final Supplier<NewLeftType> leftSupp = () -> {
- if(pairBound) return mapper.apply(boundPair.getLeft());
-
- final NewLeft leftVal = binder.apply(oldSupplier.get()).getLeft();
-
- return mapper.apply(leftVal);
- };
-
- final Supplier<NewRight> rightSupp = () -> {
- if(pairBound) return boundPair.getRight();
-
- return binder.apply(oldSupplier.get()).getRight();
- };
-
- return new LazyPair<>(leftSupp, rightSupp);
- }
-
- @Override
- public <NewRightType> IPair<NewLeft, NewRightType> mapRight(final Function<NewRight, NewRightType> mapper) {
- final Supplier<NewLeft> leftSupp = () -> {
- if(pairBound) return boundPair.getLeft();
-
- return binder.apply(oldSupplier.get()).getLeft();
- };
-
- final Supplier<NewRightType> rightSupp = () -> {
- if(pairBound) return mapper.apply(boundPair.getRight());
-
- final NewRight rightVal = binder.apply(oldSupplier.get()).getRight();
-
- return mapper.apply(rightVal);
- };
-
- return new LazyPair<>(leftSupp, rightSupp);
- }
-
- @Override
- public <MergedType> MergedType merge(final BiFunction<NewLeft, NewRight, MergedType> merger) {
- if(!pairBound) {
- boundPair = binder.apply(oldSupplier.get());
-
- pairBound = true;
- }
-
- return boundPair.merge(merger);
- }
-}