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miorelmiorel
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Add Java SimpleIterator goody (#165)
This makes it easy to implement an `Iterator` while providing only a `next()` method. The `hasNext()` method is then filled in for you via the `toIterator` method.
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7 files changed

+180
-3
lines changed

7 files changed

+180
-3
lines changed

‎tools/adventure-pack/goodies/java/build.gradle.kts‎

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@@ -48,3 +48,9 @@ tasks.register<KtfmtFormatTask>("ktfmtCustom") {
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source = project.fileTree(rootDir)
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include("*.gradle.kts")
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}
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tasks.withType<JavaCompile> {
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options.compilerArgs.add("-Xlint:all")
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options.compilerArgs.add("-Werror")
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options.isWarnings = true
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}

‎tools/adventure-pack/goodies/java/src/simple_iterator/SimpleIterator.java‎

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@@ -0,0 +1,52 @@
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package simple_iterator;
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import java.util.Iterator;
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import java.util.NoSuchElementException;
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public interface SimpleIterator<T> {
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public T next();
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static enum HasNextState {
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TRUE,
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FALSE,
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UNKNOWN,
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}
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public static <T> Iterator<T> toIterator(final SimpleIterator<T> iterator) {
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final HasNextState[] hasNextState = { HasNextState.UNKNOWN };
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final Object[] elementReserve = { null };
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return new Iterator<T>() {
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public boolean hasNext() {
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if (hasNextState[0] == HasNextState.UNKNOWN) {
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try {
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elementReserve[0] = iterator.next();
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hasNextState[0] = HasNextState.TRUE;
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} catch (NoSuchElementException e) {
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hasNextState[0] = HasNextState.FALSE;
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}
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}
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return hasNextState[0] == HasNextState.TRUE;
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}
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public T next() {
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if (hasNextState[0] == HasNextState.TRUE) {
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hasNextState[0] = HasNextState.UNKNOWN;
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@SuppressWarnings("unchecked")
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T element = (T) elementReserve[0];
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elementReserve[0] = null;
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return element;
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}
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if (hasNextState[0] == HasNextState.UNKNOWN) {
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return iterator.next();
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}
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throw new NoSuchElementException();
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}
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};
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}
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}

‎tools/adventure-pack/goodies/java/src/simple_iterator/goody.json‎

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@@ -0,0 +1,3 @@
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{
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"name": "SimpleIterator"
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}

‎tools/adventure-pack/goodies/java/src/to_iterable/AP.java‎

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@@ -2,7 +2,7 @@
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final class AP {
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5-
public static <T> Iterable<T> toIterable(Iterator<T> iterator) {
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public static <T> Iterable<T> toIterable(final Iterator<T> iterator) {
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return () -> iterator;
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}
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}

‎tools/adventure-pack/goodies/kotlin/build.gradle.kts‎

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@@ -44,3 +44,5 @@ tasks.register<KtfmtFormatTask>("ktfmtCustom") {
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include("*.gradle.kts")
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include("**/*.kt")
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}
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// TODO: Kotlin equivalent of -Xlint:all

‎tools/adventure-pack/src/app/__tests__/__snapshots__/equip-test.ts.snap‎

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@@ -10,6 +10,65 @@ record Pair<TFirst, TSecond>(TFirst first, TSecond second) {}
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/////////////////////////// END ADVENTURE PACK CODE ////////////////////////////"
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`;
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exports[`App can equip single goody: Java SimpleIterator 1`] = `
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"////////////////////////// BEGIN ADVENTURE PACK CODE ///////////////////////////
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// Adventure Pack commit fake-commit-hash
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// Running at: https://example.com/
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import java.util.Iterator;
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import java.util.NoSuchElementException;
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interface SimpleIterator<T> {
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public T next();
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static enum HasNextState {
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TRUE,
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FALSE,
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UNKNOWN,
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}
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public static <T> Iterator<T> toIterator(final SimpleIterator<T> iterator) {
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final HasNextState[] hasNextState = { HasNextState.UNKNOWN };
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final Object[] elementReserve = { null };
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return new Iterator<T>() {
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public boolean hasNext() {
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if (hasNextState[0] == HasNextState.UNKNOWN) {
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try {
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elementReserve[0] = iterator.next();
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hasNextState[0] = HasNextState.TRUE;
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} catch (NoSuchElementException e) {
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hasNextState[0] = HasNextState.FALSE;
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}
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}
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return hasNextState[0] == HasNextState.TRUE;
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}
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public T next() {
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if (hasNextState[0] == HasNextState.TRUE) {
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hasNextState[0] = HasNextState.UNKNOWN;
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@SuppressWarnings("unchecked")
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T element = (T) elementReserve[0];
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elementReserve[0] = null;
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return element;
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}
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if (hasNextState[0] == HasNextState.UNKNOWN) {
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return iterator.next();
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}
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throw new NoSuchElementException();
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}
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};
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}
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}
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/////////////////////////// END ADVENTURE PACK CODE ////////////////////////////"
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`;
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exports[`App can equip single goody: Java UnionFind 1`] = `
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"////////////////////////// BEGIN ADVENTURE PACK CODE ///////////////////////////
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// Adventure Pack commit fake-commit-hash
@@ -118,7 +177,7 @@ import java.util.Iterator;
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final class AP {
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private AP() {}
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public static <T> Iterable<T> toIterable(Iterator<T> iterator) {
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public static <T> Iterable<T> toIterable(final Iterator<T> iterator) {
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return () -> iterator;
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}
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}

‎tools/adventure-pack/src/app/__tests__/__snapshots__/render-test.ts.snap‎

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@@ -6,6 +6,61 @@ exports[`App can render goody: Java Pair 1`] = `
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record Pair<TFirst, TSecond>(TFirst first, TSecond second) {}"
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`;
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exports[`App can render goody: Java SimpleIterator 1`] = `
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"package simple_iterator;
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import java.util.Iterator;
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import java.util.NoSuchElementException;
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interface SimpleIterator<T> {
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public T next();
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static enum HasNextState {
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TRUE,
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FALSE,
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UNKNOWN,
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}
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public static <T> Iterator<T> toIterator(final SimpleIterator<T> iterator) {
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final HasNextState[] hasNextState = { HasNextState.UNKNOWN };
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final Object[] elementReserve = { null };
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return new Iterator<T>() {
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public boolean hasNext() {
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if (hasNextState[0] == HasNextState.UNKNOWN) {
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try {
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elementReserve[0] = iterator.next();
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hasNextState[0] = HasNextState.TRUE;
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} catch (NoSuchElementException e) {
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hasNextState[0] = HasNextState.FALSE;
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}
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}
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return hasNextState[0] == HasNextState.TRUE;
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}
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public T next() {
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if (hasNextState[0] == HasNextState.TRUE) {
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hasNextState[0] = HasNextState.UNKNOWN;
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@SuppressWarnings("unchecked")
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T element = (T) elementReserve[0];
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elementReserve[0] = null;
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return element;
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}
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if (hasNextState[0] == HasNextState.UNKNOWN) {
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return iterator.next();
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}
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throw new NoSuchElementException();
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}
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};
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}
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}"
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`;
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exports[`App can render goody: Java UnionFind 1`] = `
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"package union_find;
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@@ -86,7 +141,7 @@ import java.util.Iterator;
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final class AP {
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private AP() {}
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public static <T> Iterable<T> toIterable(Iterator<T> iterator) {
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public static <T> Iterable<T> toIterable(final Iterator<T> iterator) {
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return () -> iterator;
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}
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}"

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