Just another update

This commit is contained in:
Ingy döt Net 2015-02-20 00:35:01 -05:00
parent a25938f123
commit 00a190b0a6
6591 changed files with 94363 additions and 23227 deletions

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@ -1,53 +1,25 @@
interface Function<A, B> {
public B call(A x);
}
public class YCombinator {
interface RecursiveFunc<F> extends Function<RecursiveFunc<F>, F> { }
public static <A,B> Function<A,B> fix(final Function<Function<A,B>, Function<A,B>> f) {
RecursiveFunc<Function<A,B>> r =
new RecursiveFunc<Function<A,B>>() {
public Function<A,B> call(final RecursiveFunc<Function<A,B>> w) {
return f.call(new Function<A,B>() {
public B call(A x) {
return w.call(w).call(x);
}
});
}
};
return r.call(r);
}
public static void main(String[] args) {
Function<Function<Integer,Integer>, Function<Integer,Integer>> almost_fib =
new Function<Function<Integer,Integer>, Function<Integer,Integer>>() {
public Function<Integer,Integer> call(final Function<Integer,Integer> f) {
return new Function<Integer,Integer>() {
public Integer call(Integer n) {
if (n <= 2) return 1;
return f.call(n - 1) + f.call(n - 2);
}
};
}
};
Function<Function<Integer,Integer>, Function<Integer,Integer>> almost_fac =
new Function<Function<Integer,Integer>, Function<Integer,Integer>>() {
public Function<Integer,Integer> call(final Function<Integer,Integer> f) {
return new Function<Integer,Integer>() {
public Integer call(Integer n) {
if (n <= 1) return 1;
return n * f.call(n - 1);
}
};
}
};
Function<Integer,Integer> fib = fix(almost_fib);
Function<Integer,Integer> fac = fix(almost_fac);
System.out.println("fib(10) = " + fib.call(10));
System.out.println("fac(10) = " + fac.call(10));
}
import java.util.function.Function;
public interface YCombinator {
interface RecursiveFunction<F> extends Function<RecursiveFunction<F>, F> { }
public static <A,B> Function<A,B> Y(Function<Function<A,B>, Function<A,B>> f) {
RecursiveFunction<Function<A,B>> r = w -> f.apply(x -> w.apply(w).apply(x));
return r.apply(r);
}
public static void main(String... arguments) {
Function<Integer,Integer> fib = Y(f -> n ->
(n <= 2)
? 1
: (f.apply(n - 1) + f.apply(n - 2))
);
Function<Integer,Integer> fac = Y(f -> n ->
(n <= 1)
? 1
: (n * f.apply(n - 1));
);
System.out.println("fib(10) = " + fib.apply(10));
System.out.println("fac(10) = " + fac.apply(10));
}
}

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@ -1,23 +1,3 @@
import java.util.function.Function;
public class YCombinator {
interface RecursiveFunc<F> extends Function<RecursiveFunc<F>, F> { }
public static <A,B> Function<A,B> fix(Function<Function<A,B>, Function<A,B>> f) {
RecursiveFunc<Function<A,B>> r = w -> f.apply(x -> w.apply(w).apply(x));
return r.apply(r);
public static <A,B> Function<A,B> Y(Function<Function<A,B>, Function<A,B>> f) {
return x -> f.apply(Y(f)).apply(x);
}
public static void main(String[] args) {
Function<Integer,Integer> fib = fix(f -> n -> {
if (n <= 2) return 1;
return f.apply(n - 1) + f.apply(n - 2);
});
Function<Integer,Integer> fac = fix(f -> n -> {
if (n <= 1) return 1;
return n * f.apply(n - 1);
});
System.out.println("fib(10) = " + fib.apply(10));
System.out.println("fac(10) = " + fac.apply(10));
}
}

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@ -1,8 +1,53 @@
import java.util.function.Function;
@FunctionalInterface
public interface SelfApplicable<OUTPUT> extends Function<SelfApplicable<OUTPUT>, OUTPUT> {
public default OUTPUT selfApply() {
return apply(this);
}
interface Function<A, B> {
public B call(A x);
}
public class YCombinator {
interface RecursiveFunc<F> extends Function<RecursiveFunc<F>, F> { }
public static <A,B> Function<A,B> fix(final Function<Function<A,B>, Function<A,B>> f) {
RecursiveFunc<Function<A,B>> r =
new RecursiveFunc<Function<A,B>>() {
public Function<A,B> call(final RecursiveFunc<Function<A,B>> w) {
return f.call(new Function<A,B>() {
public B call(A x) {
return w.call(w).call(x);
}
});
}
};
return r.call(r);
}
public static void main(String[] args) {
Function<Function<Integer,Integer>, Function<Integer,Integer>> almost_fib =
new Function<Function<Integer,Integer>, Function<Integer,Integer>>() {
public Function<Integer,Integer> call(final Function<Integer,Integer> f) {
return new Function<Integer,Integer>() {
public Integer call(Integer n) {
if (n <= 2) return 1;
return f.call(n - 1) + f.call(n - 2);
}
};
}
};
Function<Function<Integer,Integer>, Function<Integer,Integer>> almost_fac =
new Function<Function<Integer,Integer>, Function<Integer,Integer>>() {
public Function<Integer,Integer> call(final Function<Integer,Integer> f) {
return new Function<Integer,Integer>() {
public Integer call(Integer n) {
if (n <= 1) return 1;
return n * f.call(n - 1);
}
};
}
};
Function<Integer,Integer> fib = fix(almost_fib);
Function<Integer,Integer> fac = fix(almost_fac);
System.out.println("fib(10) = " + fib.call(10));
System.out.println("fac(10) = " + fac.call(10));
}
}

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@ -1,5 +1,8 @@
import java.util.function.Function;
import java.util.function.UnaryOperator;
@FunctionalInterface
public interface FixedPoint<FUNCTION> extends Function<UnaryOperator<FUNCTION>, FUNCTION> {}
public interface SelfApplicable<OUTPUT> extends Function<SelfApplicable<OUTPUT>, OUTPUT> {
public default OUTPUT selfApply() {
return apply(this);
}
}

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@ -1,43 +1,5 @@
import java.util.Arrays;
import java.util.Optional;
import java.util.function.Function;
import java.util.function.BiFunction;
import java.util.function.UnaryOperator;
@FunctionalInterface
public interface VarargsFunction<INPUTS, OUTPUT> extends Function<INPUTS[], OUTPUT> {
@SuppressWarnings("unchecked")
public OUTPUT apply(INPUTS... inputs);
public static <INPUTS, OUTPUT> VarargsFunction<INPUTS, OUTPUT> from(Function<INPUTS[], OUTPUT> function) {
return function::apply;
}
public static <INPUTS, OUTPUT> VarargsFunction<INPUTS, OUTPUT> upgrade(Function<INPUTS, OUTPUT> function) {
return inputs -> function.apply(inputs[0]);
}
public static <INPUTS, OUTPUT> VarargsFunction<INPUTS, OUTPUT> upgrade(BiFunction<INPUTS, INPUTS, OUTPUT> function) {
return inputs -> function.apply(inputs[0], inputs[1]);
}
@SuppressWarnings("unchecked")
public default <POST_OUTPUT> VarargsFunction<INPUTS, POST_OUTPUT> andThen(
VarargsFunction<OUTPUT, POST_OUTPUT> after) {
return inputs -> after.apply(apply(inputs));
}
@SuppressWarnings("unchecked")
public default Function<INPUTS, OUTPUT> toFunction() {
return input -> apply(input);
}
@SuppressWarnings("unchecked")
public default BiFunction<INPUTS, INPUTS, OUTPUT> toBiFunction() {
return (input, input2) -> apply(input, input2);
}
@SuppressWarnings("unchecked")
public default <PRE_INPUTS> VarargsFunction<PRE_INPUTS, OUTPUT> transformArguments(Function<PRE_INPUTS, INPUTS> transformer) {
return inputs -> apply((INPUTS[]) Arrays.stream(inputs).parallel().map(transformer).toArray());
}
}
public interface FixedPoint<FUNCTION> extends Function<UnaryOperator<FUNCTION>, FUNCTION> {}

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@ -1,74 +1,43 @@
import java.math.BigDecimal;
import java.math.BigInteger;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;
import java.util.Optional;
import java.util.function.Function;
import java.util.function.UnaryOperator;
import java.util.stream.Collectors;
import java.util.stream.LongStream;
import java.util.function.BiFunction;
@FunctionalInterface
public interface Y<FUNCTION> extends SelfApplicable<FixedPoint<FUNCTION>> {
public static void main(String... arguments) {
BigInteger TWO = BigInteger.ONE.add(BigInteger.ONE);
public interface VarargsFunction<INPUTS, OUTPUT> extends Function<INPUTS[], OUTPUT> {
@SuppressWarnings("unchecked")
public OUTPUT apply(INPUTS... inputs);
Function<Number, Long> toLong = Number::longValue;
Function<Number, BigInteger> toBigInteger = toLong.andThen(BigInteger::valueOf);
public static <INPUTS, OUTPUT> VarargsFunction<INPUTS, OUTPUT> from(Function<INPUTS[], OUTPUT> function) {
return function::apply;
}
/* Based on https://gist.github.com/aruld/3965968/#comment-604392 */
Y<VarargsFunction<Number, Number>> combinator = y -> f -> x -> f.apply(y.selfApply().apply(f)).apply(x);
FixedPoint<VarargsFunction<Number, Number>> fixedPoint = combinator.selfApply();
public static <INPUTS, OUTPUT> VarargsFunction<INPUTS, OUTPUT> upgrade(Function<INPUTS, OUTPUT> function) {
return inputs -> function.apply(inputs[0]);
}
VarargsFunction<Number, Number> fibonacci = fixedPoint.apply(
f -> VarargsFunction.upgrade(
toBigInteger.andThen(
n -> (n.compareTo(TWO) <= 0)
? 1
: new BigInteger(f.apply(n.subtract(BigInteger.ONE)).toString())
.add(new BigInteger(f.apply(n.subtract(TWO)).toString()))
)
)
);
public static <INPUTS, OUTPUT> VarargsFunction<INPUTS, OUTPUT> upgrade(BiFunction<INPUTS, INPUTS, OUTPUT> function) {
return inputs -> function.apply(inputs[0], inputs[1]);
}
VarargsFunction<Number, Number> factorial = fixedPoint.apply(
f -> VarargsFunction.upgrade(
toBigInteger.andThen(
n -> (n.compareTo(BigInteger.ONE) <= 0)
? 1
: n.multiply(new BigInteger(f.apply(n.subtract(BigInteger.ONE)).toString()))
)
)
);
@SuppressWarnings("unchecked")
public default <POST_OUTPUT> VarargsFunction<INPUTS, POST_OUTPUT> andThen(
VarargsFunction<OUTPUT, POST_OUTPUT> after) {
return inputs -> after.apply(apply(inputs));
}
VarargsFunction<Number, Number> ackermann = fixedPoint.apply(
f -> VarargsFunction.upgrade(
(BigInteger m, BigInteger n) -> m.equals(BigInteger.ZERO)
? n.add(BigInteger.ONE)
: f.apply(
m.subtract(BigInteger.ONE),
n.equals(BigInteger.ZERO)
? BigInteger.ONE
: f.apply(m, n.subtract(BigInteger.ONE))
)
).transformArguments(toBigInteger)
);
@SuppressWarnings("unchecked")
public default Function<INPUTS, OUTPUT> toFunction() {
return input -> apply(input);
}
Map<String, VarargsFunction<Number, Number>> functions = new HashMap<>();
functions.put("fibonacci", fibonacci);
functions.put("factorial", factorial);
functions.put("ackermann", ackermann);
@SuppressWarnings("unchecked")
public default BiFunction<INPUTS, INPUTS, OUTPUT> toBiFunction() {
return (input, input2) -> apply(input, input2);
}
Map<VarargsFunction<Number, Number>, Number[]> parameters = new HashMap<>();
parameters.put(functions.get("fibonacci"), new Number[]{20});
parameters.put(functions.get("factorial"), new Number[]{10});
parameters.put(functions.get("ackermann"), new Number[]{3, 2});
functions.entrySet().stream().parallel().map(
entry -> entry.getKey()
+ Arrays.toString(parameters.get(entry.getValue()))
+ " = "
+ entry.getValue().apply(parameters.get(entry.getValue()))
).forEach(System.out::println);
@SuppressWarnings("unchecked")
public default <PRE_INPUTS> VarargsFunction<PRE_INPUTS, OUTPUT> transformArguments(Function<PRE_INPUTS, INPUTS> transformer) {
return inputs -> apply((INPUTS[]) Arrays.stream(inputs).parallel().map(transformer).toArray());
}
}

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@ -1,3 +1,74 @@
factorial[10] = 3628800
ackermann[3, 2] = 29
fibonacci[20] = 6765
import java.math.BigDecimal;
import java.math.BigInteger;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;
import java.util.function.Function;
import java.util.function.UnaryOperator;
import java.util.stream.Collectors;
import java.util.stream.LongStream;
@FunctionalInterface
public interface Y<FUNCTION> extends SelfApplicable<FixedPoint<FUNCTION>> {
public static void main(String... arguments) {
BigInteger TWO = BigInteger.ONE.add(BigInteger.ONE);
Function<Number, Long> toLong = Number::longValue;
Function<Number, BigInteger> toBigInteger = toLong.andThen(BigInteger::valueOf);
/* Based on https://gist.github.com/aruld/3965968/#comment-604392 */
Y<VarargsFunction<Number, Number>> combinator = y -> f -> x -> f.apply(y.selfApply().apply(f)).apply(x);
FixedPoint<VarargsFunction<Number, Number>> fixedPoint = combinator.selfApply();
VarargsFunction<Number, Number> fibonacci = fixedPoint.apply(
f -> VarargsFunction.upgrade(
toBigInteger.andThen(
n -> (n.compareTo(TWO) <= 0)
? 1
: new BigInteger(f.apply(n.subtract(BigInteger.ONE)).toString())
.add(new BigInteger(f.apply(n.subtract(TWO)).toString()))
)
)
);
VarargsFunction<Number, Number> factorial = fixedPoint.apply(
f -> VarargsFunction.upgrade(
toBigInteger.andThen(
n -> (n.compareTo(BigInteger.ONE) <= 0)
? 1
: n.multiply(new BigInteger(f.apply(n.subtract(BigInteger.ONE)).toString()))
)
)
);
VarargsFunction<Number, Number> ackermann = fixedPoint.apply(
f -> VarargsFunction.upgrade(
(BigInteger m, BigInteger n) -> m.equals(BigInteger.ZERO)
? n.add(BigInteger.ONE)
: f.apply(
m.subtract(BigInteger.ONE),
n.equals(BigInteger.ZERO)
? BigInteger.ONE
: f.apply(m, n.subtract(BigInteger.ONE))
)
).transformArguments(toBigInteger)
);
Map<String, VarargsFunction<Number, Number>> functions = new HashMap<>();
functions.put("fibonacci", fibonacci);
functions.put("factorial", factorial);
functions.put("ackermann", ackermann);
Map<VarargsFunction<Number, Number>, Number[]> parameters = new HashMap<>();
parameters.put(functions.get("fibonacci"), new Number[]{20});
parameters.put(functions.get("factorial"), new Number[]{10});
parameters.put(functions.get("ackermann"), new Number[]{3, 2});
functions.entrySet().stream().parallel().map(
entry -> entry.getKey()
+ Arrays.toString(parameters.get(entry.getValue()))
+ " = "
+ entry.getValue().apply(parameters.get(entry.getValue()))
).forEach(System.out::println);
}
}

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@ -0,0 +1,3 @@
factorial[10] = 3628800
ackermann[3, 2] = 29
fibonacci[20] = 6765