Mercurial > hg > Members > tatsuki > functionaljava-master > core
view src/main/java/fj/Show.java @ 0:fe80c1edf1be
add getLoop
author | tatsuki |
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date | Fri, 20 Mar 2015 21:04:03 +0900 |
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package fj; import fj.data.Array; import fj.data.Either; import fj.data.LazyString; import fj.data.List; import fj.data.Natural; import fj.data.NonEmptyList; import fj.data.Option; import fj.data.Stream; import fj.data.Tree; import fj.data.Validation; import fj.data.hlist.HList; import fj.data.vector.V2; import fj.data.vector.V3; import fj.data.vector.V4; import fj.data.vector.V5; import fj.data.vector.V6; import fj.data.vector.V7; import fj.data.vector.V8; import java.math.BigDecimal; import java.math.BigInteger; import static fj.Function.compose; import static fj.P.p; import static fj.Unit.unit; import static fj.data.Stream.cons; import static fj.data.Stream.fromString; import static fj.data.Stream.join; import static fj.data.Stream.nil; import static fj.data.Stream.single; /** * Renders an object for display. * * @version %build.number% */ public final class Show<A> { private final F<A, Stream<Character>> f; private Show(final F<A, Stream<Character>> f) { this.f = f; } /** * Maps the given function across this show as a contra-variant functor. * * @param f The function to map. * @return A new show. */ public <B> Show<B> comap(final F<B, A> f) { return show(compose(this.f, f)); } /** * Returns the display rendering of the given argument. * * @param a The argument to display. * @return The display rendering of the given argument. */ public Stream<Character> show(final A a) { return f.f(a); } /** * Returns the display rendering of the given argument. * * @param a The argument to display. * @return The display rendering of the given argument. */ public List<Character> showl(final A a) { return show(a).toList(); } /** * Returns the display rendering of the given argument as a <code>String</code>. * * @param a The argument to display. * @return The display rendering of the given argument as a <code>String</code>. */ public String showS(final A a) { return Stream.asString(show(a)); } /** * Returns the transformation equivalent to this show. * * @return the transformation equivalent to this show. */ public F<A, String> showS_() { return new F<A, String>() { public String f(final A a) { return showS(a); } }; } /** * Returns the transformation equivalent to this show. * * @return the transformation equivalent to this show. */ public F<A, Stream<Character>> show_() { return f; } /** * Prints the given argument to the standard output stream with a new line. * * @param a The argument to print. * @return The unit value. */ public Unit println(final A a) { print(a); System.out.println(); return unit(); } /** * Prints the given argument to the standard output stream. * * @param a The argument to print. * @return The unit value. */ public Unit print(final A a) { final char[] buffer = new char[8192]; int c = 0; for (Stream<Character> cs = show(a); cs.isNotEmpty(); cs = cs.tail()._1()) { buffer[c] = cs.head(); c++; if (c == 8192) { System.out.print(buffer); c = 0; } } System.out.print(Array.copyOfRange(buffer, 0, c)); return unit(); } /** * Prints the given argument to the standard error stream with a new line. * * @param a The argument to print. */ public void printlnE(final A a) { System.err.println(showS(a)); } /** * Returns a show instance using the given function. * * @param f The function to use for the returned show instance. * @return A show instance. */ public static <A> Show<A> show(final F<A, Stream<Character>> f) { return new Show<A>(f); } /** * Returns a show instance using the given function. * * @param f The function to use for the returned show instance. * @return A show instance. */ public static <A> Show<A> showS(final F<A, String> f) { return new Show<A>(new F<A, Stream<Character>>() { public Stream<Character> f(final A a) { return fromString(f.f(a)); } }); } /** * Returns a show instance that uses {@link Object#toString()} to perform the display rendering. * * @return A show instance that uses {@link Object#toString()} to perform the display rendering. */ public static <A> Show<A> anyShow() { return new Show<A>(new F<A, Stream<Character>>() { public Stream<Character> f(final A a) { return Stream.fromString((a == null) ? "null" : a.toString()); } }); } /** * A show instance for the <code>boolean</code> type. */ public static final Show<Boolean> booleanShow = anyShow(); /** * A show instance for the <code>byte</code> type. */ public static final Show<Byte> byteShow = anyShow(); /** * A show instance for the <code>char</code> type. */ public static final Show<Character> charShow = anyShow(); /** * A show instance for the <code>double</code> type. */ public static final Show<Double> doubleShow = anyShow(); /** * A show instance for the <code>float</code> type. */ public static final Show<Float> floatShow = anyShow(); /** * A show instance for the <code>int</code> type. */ public static final Show<Integer> intShow = anyShow(); /** * A show instance for the <code>BigInteger</code> type. */ public static final Show<BigInteger> bigintShow = anyShow(); /** * A show instance for the <code>BigDecimal</code> type. */ public static final Show<BigDecimal> bigdecimalShow = anyShow(); /** * A show instance for the <code>long</code> type. */ public static final Show<Long> longShow = anyShow(); /** * A show instance for the <code>short</code> type. */ public static final Show<Short> shortShow = anyShow(); /** * A show instance for the {@link String} type. */ public static final Show<String> stringShow = anyShow(); /** * A show instance for the {@link StringBuffer} type. */ public static final Show<StringBuffer> stringBufferShow = anyShow(); /** * A show instance for the {@link StringBuilder} type. */ public static final Show<StringBuilder> stringBuilderShow = anyShow(); /** * A show instance for the {@link Option} type. * * @param sa Show for the element of the option. * @return A show instance for the {@link Option} type. */ public static <A> Show<Option<A>> optionShow(final Show<A> sa) { return new Show<Option<A>>(new F<Option<A>, Stream<Character>>() { public Stream<Character> f(final Option<A> o) { return o.isNone() ? fromString("None") : fromString("Some(").append(sa.f.f(o.some())).append(single(')')); } }); } /** * A show instance for the {@link Either} type. * * @param sa Show for the left side of the {@link Either}. * @param sb Show for the right side of the {@link Either}. * @return A show instance for the {@link Either} type. */ public static <A, B> Show<Either<A, B>> eitherShow(final Show<A> sa, final Show<B> sb) { return new Show<Either<A, B>>(new F<Either<A, B>, Stream<Character>>() { public Stream<Character> f(final Either<A, B> e) { return e.isLeft() ? fromString("Left(").append(sa.f.f(e.left().value())).append(single(')')) : fromString("Right(").append(sb.f.f(e.right().value())).append(single(')')); } }); } /** * A show instance for the {@link Validation} type. * * @param sa Show for the fail side of the {@link Validation}. * @param sb Show for the success side of the {@link Validation}. * @return A show instance for the {@link Validation} type. */ public static <A, B> Show<Validation<A, B>> validationShow(final Show<A> sa, final Show<B> sb) { return new Show<Validation<A, B>>(new F<Validation<A, B>, Stream<Character>>() { public Stream<Character> f(final Validation<A, B> v) { return v.isFail() ? fromString("Fail(").append(sa.f.f(v.fail())).append(single(')')) : fromString("Success(").append(sb.f.f(v.success())).append(single(')')); } }); } /** * A show instance for the {@link Stream} type. * * @param sa Show for the elements of the Stream. * @return A show instance for the {@link Stream} type. */ public static <A> Show<List<A>> listShow(final Show<A> sa) { return new Show<List<A>>(new F<List<A>, Stream<Character>>() { public Stream<Character> f(final List<A> as) { return streamShow(sa).show(as.toStream()); } }); } /** * A show instance for the {@link NonEmptyList} type. * * @param sa Show for the elements of the non-empty Stream. * @return A show instance for the {@link NonEmptyList} type. */ public static <A> Show<NonEmptyList<A>> nonEmptyListShow(final Show<A> sa) { return listShow(sa).comap(NonEmptyList.<A>toList_()); } /** * A show instance for the {@link Tree} type. * * @param sa Show for the elements of the tree. * @return A show instance for the {@link Tree} type. */ public static <A> Show<Tree<A>> treeShow(final Show<A> sa) { return new Show<Tree<A>>(new F<Tree<A>, Stream<Character>>() { public Stream<Character> f(final Tree<A> a) { final Stream<Character> b = sa.f.f(a.root()) .append(p1Show(streamShow(treeShow(sa))).f.f(a.subForest())) .snoc(')'); return cons('(', p(b)); } }); } /** * A show instance for the {@link Stream} type. * * @param sa Show for the elements of the stream. * @return A show instance for the {@link Stream} type. */ public static <A> Show<Stream<A>> streamShow(final Show<A> sa) { return new Show<Stream<A>>(new F<Stream<A>, Stream<Character>>() { public Stream<Character> f(final Stream<A> as) { return join(as.map(sa.show_()).intersperse(fromString(",")).cons(fromString("<")).snoc(p(fromString(">")))); } }); } /** * A show instance for the {@link Array} type. * * @param sa Show for the elements of the array. * @return A show instance for the {@link Array} type. */ public static <A> Show<Array<A>> arrayShow(final Show<A> sa) { return new Show<Array<A>>(new F<Array<A>, Stream<Character>>() { public Stream<Character> f(final Array<A> as) { Stream<Character> b = nil(); for (int i = 0; i < as.length(); i++) { b = b.append(sa.f.f(as.get(i))); if (i != as.length() - 1) b = b.snoc(','); } b = b.snoc('}'); return cons('{', p(b)); } }); } /** * A show instance for the {@link Class} type. * * @return A show instance for the {@link Class} type. */ public static <A> Show<Class<A>> classShow() { return new Show<Class<A>>(new F<fj.Class<A>, Stream<Character>>() { public Stream<Character> f(final Class<A> c) { return anyShow().show(c.clas()); } }); } /** * A show instance for the {@link P1 tuple-1} type. * * @param sa Show for the first element of the tuple. * @return A show instance for the {@link P1 tuple-1} type. */ public static <A> Show<P1<A>> p1Show(final Show<A> sa) { return new Show<P1<A>>(new F<P1<A>, Stream<Character>>() { public Stream<Character> f(final P1<A> p) { return cons('(', p(sa.show(p._1()))).snoc(')'); } }); } /** * A show instance for the {@link P2 tuple-2} type. * * @param sa Show for the first element of the tuple. * @param sb Show for the second element of the tuple. * @return A show instance for the {@link P2 tuple-2} type. */ public static <A, B> Show<P2<A, B>> p2Show(final Show<A> sa, final Show<B> sb) { return new Show<P2<A, B>>(new F<P2<A, B>, Stream<Character>>() { public Stream<Character> f(final P2<A, B> p) { return cons('(', p(sa.show(p._1()))).snoc(',').append(sb.show(p._2())).snoc(')'); } }); } /** * A show instance for the {@link P3 tuple-3} type. * * @param sa Show for the first element of the tuple. * @param sb Show for the second element of the tuple. * @param sc Show for the third element of the tuple. * @return A show instance for the {@link P3 tuple-3} type. */ public static <A, B, C> Show<P3<A, B, C>> p3Show(final Show<A> sa, final Show<B> sb, final Show<C> sc) { return new Show<P3<A, B, C>>(new F<P3<A, B, C>, Stream<Character>>() { public Stream<Character> f(final P3<A, B, C> p) { return cons('(', p(sa.show(p._1()))).snoc(',').append(sb.show(p._2())).snoc(',') .append(sc.show(p._3())).snoc(')'); } }); } /** * A show instance for the {@link P4 tuple-4} type. * * @param sa Show for the first element of the tuple. * @param sb Show for the second element of the tuple. * @param sc Show for the third element of the tuple. * @param sd Show for the fourth element of the tuple. * @return A show instance for the {@link P4 tuple-4} type. */ public static <A, B, C, D> Show<P4<A, B, C, D>> p4Show(final Show<A> sa, final Show<B> sb, final Show<C> sc, final Show<D> sd) { return new Show<P4<A, B, C, D>>(new F<P4<A, B, C, D>, Stream<Character>>() { public Stream<Character> f(final P4<A, B, C, D> p) { return cons('(', p(sa.show(p._1()))).snoc(',').append(sb.show(p._2())).snoc(',') .append(sc.show(p._3())).snoc(',').append(sd.show(p._4())).snoc(')'); } }); } /** * A show instance for the {@link P5 tuple-5} type. * * @param sa Show for the first element of the tuple. * @param sb Show for the second element of the tuple. * @param sc Show for the third element of the tuple. * @param sd Show for the fourth element of the tuple. * @param se Show for the fifth element of the tuple. * @return A show instance for the {@link P5 tuple-5} type. */ public static <A, B, C, D, E> Show<P5<A, B, C, D, E>> p5Show(final Show<A> sa, final Show<B> sb, final Show<C> sc, final Show<D> sd, final Show<E> se) { return new Show<P5<A, B, C, D, E>>(new F<P5<A, B, C, D, E>, Stream<Character>>() { public Stream<Character> f(final P5<A, B, C, D, E> p) { return cons('(', p(sa.show(p._1()))).snoc(',').append(sb.show(p._2())).snoc(',') .append(sc.show(p._3())).snoc(',').append(sd.show(p._4())).snoc(',').append(se.show(p._5())).snoc(')'); } }); } /** * A show instance for the {@link P6 tuple-6} type. * * @param sa Show for the first element of the tuple. * @param sb Show for the second element of the tuple. * @param sc Show for the third element of the tuple. * @param sd Show for the fourth element of the tuple. * @param se Show for the fifth element of the tuple. * @param sf Show for the sixth element of the tuple. * @return A show instance for the {@link P6 tuple-6} type. */ public static <A, B, C, D, E, F$> Show<P6<A, B, C, D, E, F$>> p6Show(final Show<A> sa, final Show<B> sb, final Show<C> sc, final Show<D> sd, final Show<E> se, final Show<F$> sf) { return new Show<P6<A, B, C, D, E, F$>>(new F<P6<A, B, C, D, E, F$>, Stream<Character>>() { public Stream<Character> f(final P6<A, B, C, D, E, F$> p) { return cons('(', p(sa.show(p._1()))).snoc(',').append(sb.show(p._2())).snoc(',') .append(sc.show(p._3())).snoc(',').append(sd.show(p._4())).snoc(',') .append(se.show(p._5())).snoc(',').append(sf.show(p._6())).snoc(')'); } }); } /** * A show instance for the {@link P7 tuple-7} type. * * @param sa Show for the first element of the tuple. * @param sb Show for the second element of the tuple. * @param sc Show for the third element of the tuple. * @param sd Show for the fourth element of the tuple. * @param se Show for the fifth element of the tuple. * @param sf Show for the sixth element of the tuple. * @param sg Show for the seventh element of the tuple. * @return A show instance for the {@link P7 tuple-7} type. */ public static <A, B, C, D, E, F$, G> Show<P7<A, B, C, D, E, F$, G>> p7Show(final Show<A> sa, final Show<B> sb, final Show<C> sc, final Show<D> sd, final Show<E> se, final Show<F$> sf, final Show<G> sg) { return new Show<P7<A, B, C, D, E, F$, G>>(new F<P7<A, B, C, D, E, F$, G>, Stream<Character>>() { public Stream<Character> f(final P7<A, B, C, D, E, F$, G> p) { return cons('(', p(sa.show(p._1()))).snoc(',').append(sb.show(p._2())).snoc(',') .append(sc.show(p._3())).snoc(',').append(sd.show(p._4())).snoc(',') .append(se.show(p._5())).snoc(',').append(sf.show(p._6())).snoc(',').append(sg.show(p._7())).snoc(')'); } }); } /** * A show instance for the {@link P8 tuple-8} type. * * @param sa Show for the first element of the tuple. * @param sb Show for the second element of the tuple. * @param sc Show for the third element of the tuple. * @param sd Show for the fourth element of the tuple. * @param se Show for the fifth element of the tuple. * @param sf Show for the sixth element of the tuple. * @param sg Show for the seventh element of the tuple. * @param sh Show for the eighth element of the tuple. * @return A show instance for the {@link P8 tuple-8} type. */ public static <A, B, C, D, E, F$, G, H> Show<P8<A, B, C, D, E, F$, G, H>> p8Show(final Show<A> sa, final Show<B> sb, final Show<C> sc, final Show<D> sd, final Show<E> se, final Show<F$> sf, final Show<G> sg, final Show<H> sh) { return new Show<P8<A, B, C, D, E, F$, G, H>>(new F<P8<A, B, C, D, E, F$, G, H>, Stream<Character>>() { public Stream<Character> f(final P8<A, B, C, D, E, F$, G, H> p) { return cons('(', p(sa.show(p._1()))).snoc(',').append(sb.show(p._2())).snoc(',') .append(sc.show(p._3())).snoc(',').append(sd.show(p._4())).snoc(',') .append(se.show(p._5())).snoc(',').append(sf.show(p._6())).snoc(',') .append(sg.show(p._7())).snoc(',').append(sh.show(p._8())).snoc(')'); } }); } /** * A show instance for a vector-2. * * @param ea A show for the elements of the vector. * @return A show instance for a vector-2. */ public static <A> Show<V2<A>> v2Show(final Show<A> ea) { return streamShow(ea).comap(V2.<A>toStream_()); } /** * A show instance for a vector-3. * * @param ea A show for the elements of the vector. * @return A show instance for a vector-3. */ public static <A> Show<V3<A>> v3Show(final Show<A> ea) { return streamShow(ea).comap(V3.<A>toStream_()); } /** * A show instance for a vector-4. * * @param ea A show for the elements of the vector. * @return A show instance for a vector-4. */ public static <A> Show<V4<A>> v4Show(final Show<A> ea) { return streamShow(ea).comap(V4.<A>toStream_()); } /** * A show instance for a vector-5. * * @param ea A show for the elements of the vector. * @return A show instance for a vector-5. */ public static <A> Show<V5<A>> v5Show(final Show<A> ea) { return streamShow(ea).comap(V5.<A>toStream_()); } /** * A show instance for a vector-6. * * @param ea A show for the elements of the vector. * @return A show instance for a vector-6. */ public static <A> Show<V6<A>> v6Show(final Show<A> ea) { return streamShow(ea).comap(V6.<A>toStream_()); } /** * A show instance for a vector-7. * * @param ea A show for the elements of the vector. * @return A show instance for a vector-7. */ public static <A> Show<V7<A>> v7Show(final Show<A> ea) { return streamShow(ea).comap(V7.<A>toStream_()); } /** * A show instance for a vector-8. * * @param ea A show for the elements of the vector. * @return A show instance for a vector-8. */ public static <A> Show<V8<A>> v8Show(final Show<A> ea) { return streamShow(ea).comap(V8.<A>toStream_()); } /** * A show instance for natural numbers. */ public static final Show<Natural> naturalShow = bigintShow.comap(new F<Natural, BigInteger>() { public BigInteger f(final Natural natural) { return natural.bigIntegerValue(); } }); /** * A show instance for streams that splits into lines. * * @param sa A show instance for the elements of a stream. * @return A show instance for streams that splits into lines. */ public static <A> Show<Stream<A>> unlineShow(final Show<A> sa) { return new Show<Stream<A>>(new F<Stream<A>, Stream<Character>>() { public Stream<Character> f(final Stream<A> as) { return join(as.map(sa.show_()).intersperse(fromString("\n"))); } }); } /** * A show instance for lazy strings. */ public static final Show<LazyString> lazyStringShow = show(new F<LazyString, Stream<Character>>() { public Stream<Character> f(final LazyString string) { return string.toStream(); } }); /** * A show instance for the empty heterogeneous Stream. */ public static final Show<HList.HNil> HListShow = showS(Function.<HList.HNil, String>constant("Nil")); /** * A show instance for heterogeneous Streams. * * @param e A show instance for the first element of the Stream. * @param l A show instance for the rest of the Stream. * @return a show instance for heterogeneous Streams. */ public static <E, L extends HList<L>> Show<HList.HCons<E, L>> HListShow(final Show<E> e, final Show<L> l) { return show(new F<HList.HCons<E, L>, Stream<Character>>() { public Stream<Character> f(final HList.HCons<E, L> c) { return e.show(c.head()).cons('[').append(l.show(c.tail())).snoc(']'); } }); } }