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package name.panitz.util;
import java.util.Iterator;
import java.math.BigInteger;
import java.util.function.Function;
import java.util.function.Predicate;
public interface Iteratoren {
public static class IntRange implements Iterable<Integer>{
int from;
int to;
int step;
boolean infinite;
public IntRange(int from, int to, int step){/*ToDo*/}
public IntRange(int from, int to){/*ToDo*/}
public IntRange(int from){/*ToDo*/}
public IntRange(){/*ToDo*/}
}
public static class Fib implements Iterable<BigInteger> {
@Override public Iterator<BigInteger> iterator(){
return null; /*ToDo*/
}
public static void main(String[] args){
new Fib().forEach(x-> System.out.println(x));
}
}
public static class ArrayIterable<A> implements Iterable<A>{
A[] as;
public ArrayIterable(A[] as){
this.as = as;
}
}
public static class IterableString implements Iterable<Character> {
public IterableString(String str){
}
public static void main(String[] args){
for (char c:new IterableString("Hello world!")){
System.out.println(c);
}
}
}
public static class Lines implements Iterable<String> {
static String NEW_LINE = System.getProperty("line.separator");
public Lines(String str){
/*ToDo*/
}
@Override public Iterator<String> iterator() {
return /*ToDo*/;
}
public static void main(String[] args) {
for (String s:new Lines("hallo"+NEW_LINE+"welt!"))
System.out.println(s);
}
}
public static class Words implements Iterable<String>{
public Words(String text){
}
}
public class IndexIterable<A> implements Iterable<A> {
public IndexIterable(Function<Long, A> f) {
}
}
public static class GenerationIterable<A> implements Iterable<A> {
A a;
Function<A,A> f;
public GenerationIterable(A a, Function<A,A> f){
this.a = a;
this.f = f;
}
}
public static class OddIterable extends GenerationIterable<Long>{
public OddIterable() {
//hier der korrekte Aufruf....
}
}
public static record Limit<A>(Iterable<A> itA, long n)
implements Iterable<A>{
public Iterator<A> iterator(){
return new Iterator<>(){
Iterator<A> it = itA.iterator();
int i = 0;
/* ToDo */
};
}
}
public static record Maperable<A,R>(Iterable<A> itA, Function<A,R> f)
implements Iterable<R>{
public Iterator<R> iterator(){
return new Iterator<>(){
Iterator<A> it = itA.iterator();
/* ToDo */
};
}
}
public static record Filterable<A>(Iterable<A> itA, Predicate<A> p)
implements Iterable<A>{
public Iterator<A> iterator(){
return new MyIterator();
}
private class MyIterator implements Iterator<A>{
Iterator<A> it = itA.iterator();
A theNext = null;
MyIterator(){getTheNext();}
void getTheNext(){
/* ToDo store the element,
for which the predicate p holds in theNext */
}
public boolean hasNext(){return theNext!=null;}
public A next(){
var result = theNext;
getTheNext();
return result;}
}
}
}
Subato
