split map() with default arguments into map() and mapTo(resultCollection) to simplify IDE/completion/compiler error messages

build.xml

@@ -151,6 +151,20 @@
         </java>
     </target>
 
+    <target name="generateStdlib" depends="compileTestlib" description="Generates the stdlib APIs for arrays and kotlin collections">
+        <java classname="kotlin.tools.namespace" failonerror="true" fork="true">
+            <classpath>
+                <pathelement location="${kotlin-home}/lib/kotlin-runtime.jar"/>
+                <pathelement location="${kotlin-home}/lib/kotlin-test.jar"/>
+                <pathelement location="${basedir}/testlib/lib/junit-4.9.jar"/>
+                <fileset dir="${basedir}/testlib/lib">
+                  <include name="**/*.jar"/>
+                </fileset>
+              <pathelement path="${output}/classes/testlib"/>
+            </classpath>
+        </java>
+    </target>
+
     <target name="testlib" depends="compileTestlib">
         <mkdir dir="${output}/test-reports"/>
 

stdlib/ktSrc/Arrays.kt

@@ -104,3 +104,18 @@ inline fun ByteArray.inputStream(offset: Int, length: Int) = ByteArrayInputStrea
 /** Returns true if the array is not empty */
 inline fun <T> Array<T>.notEmpty() : Boolean = this.size > 0
 
+/** Returns true if the array is empty */
+inline fun <T> Array<T>.isEmpty() : Boolean = this.size == 0
+
+
+/** Returns a new List containing the results of applying the given function to each element in this collection */
+inline fun <T, R> Array<T>.map(transform : (T) -> R) : java.util.List<R> {
+    return mapTo(java.util.ArrayList<R>(this.size), transform)
+}
+
+/** Transforms each element of this collection with the given function then adds the results to the given collection */
+inline fun <T, R, C: java.util.Collection<in R>> Array<T>.mapTo(result: C, transform : (T) -> R) : C {
+  for (item in this)
+    result.add(transform(item))
+  return result
+}

stdlib/ktSrc/JavaCollections.kt

@@ -1,17 +1,3 @@
 package std.util
 
 import java.util.*
-
-/** Returns a new collection containing the results of applying the given function to each element in this collection */
-inline fun <T, R> java.util.Collection<T>.map(result: Collection<R> = ArrayList<R>(this.size), transform : (T) -> R) : Collection<R> {
-  for (item in this)
-    result.add(transform(item))
-  return result
-}
-
-/** Returns true if the collection is not empty */
-inline fun <T> java.util.Collection<T>.notEmpty() : Boolean = !this.isEmpty()
-
-/** Converts the nullable collection into an empty collection if its null */
-inline fun <T> java.util.Collection<T>?.notNull() : Collection<T>
-    = if (this != null) this else Collections.EMPTY_LIST as Collection<T>

stdlib/ktSrc/JavaUtil.kt

@@ -96,4 +96,22 @@ val <T> List<T>.last : T?
     get() = this.tail
 
 
+/** Returns true if the collection is not empty */
+inline fun <T> java.util.Collection<T>.notEmpty() : Boolean = !this.isEmpty()
 
+/** Converts the nullable collection into an empty collection if its null */
+inline fun <T> java.util.Collection<T>?.notNull() : Collection<T>
+    = if (this != null) this else Collections.EMPTY_LIST as Collection<T>
+
+
+/** Returns a new List containing the results of applying the given function to each element in this collection */
+inline fun <T, R> java.util.Collection<T>.map(transform : (T) -> R) : java.util.List<R> {
+    return mapTo(java.util.ArrayList<R>(this.size), transform)
+}
+
+/** Transforms each element of this collection with the given function then adds the results to the given collection */
+inline fun <T, R, C: Collection<in R>> java.util.Collection<T>.mapTo(result: C, transform : (T) -> R) : C {
+  for (item in this)
+    result.add(transform(item))
+  return result
+}

stdlib/ktSrc/generated/ArraysFromJavaIterables.kt

@@ -1,6 +1,8 @@
 // NOTE this file is auto-generated from stdlib/ktSrc/JavaIterables.kt
 package std
 
+import std.util.*
+
 import java.util.*
 
 /** Returns true if any elements in the collection match the given predicate */
@@ -23,6 +25,16 @@ inline fun <T> Array<T>.all(predicate: (T)-> Boolean) : Boolean {
   return true
 }
 
+/** Returns the number of items which match the given predicate  */
+inline fun <T> Array<T>.count(predicate: (T)-> Boolean) : Int {
+  var answer = 0
+  for (elem in this) {
+    if (predicate(elem))
+      answer += 1
+  }
+  return answer
+}
+
 /** Returns the first item in the collection which matches the given predicate or null if none matched */
 inline fun <T> Array<T>.find(predicate: (T)-> Boolean) : T? {
   for (elem in this) {
@@ -32,8 +44,11 @@ inline fun <T> Array<T>.find(predicate: (T)-> Boolean) : T? {
   return null
 }
 
-/** Returns a new collection containing all elements in this collection which match the given predicate */
-inline fun <T> Array<T>.filter(result: Collection<T> = ArrayList<T>(), predicate: (T)-> Boolean) : Collection<T> {
+/** Returns a new List containing all elements in this collection which match the given predicate */
+inline fun <T> Array<T>.filter(predicate: (T)-> Boolean) : Collection<T> = filterTo(java.util.ArrayList<T>(), predicate)
+
+/** Filters all elements in this collection which match the given predicate into the given result collection */
+inline fun <T, C: Collection<in T>> Array<T>.filterTo(result: C, predicate: (T)-> Boolean) : C {
   for (elem in this) {
     if (predicate(elem))
       result.add(elem)
@@ -42,7 +57,10 @@ inline fun <T> Array<T>.filter(result: Collection<T> = ArrayList<T>(), predicate
 }
 
 /** Returns a new collection containing all elements in this collection which do not match the given predicate */
-inline fun <T> Array<T>.filterNot(result: Collection<T> = ArrayList<T>(), predicate: (T)-> Boolean) : Collection<T> {
+inline fun <T> Array<T>.filterNot(predicate: (T)-> Boolean) : Collection<T> =  filterNotTo(ArrayList<T>(), predicate)
+
+/** Returns a new collection containing all elements in this collection which do not match the given predicate */
+inline fun <T, C: Collection<in T>> Array<T>.filterNotTo(result: C, predicate: (T)-> Boolean) : C {
   for (elem in this) {
     if (!predicate(elem))
       result.add(elem)
@@ -72,6 +90,42 @@ inline fun <T> Array<T>.foreach(operation: (element: T) -> Unit) {
     operation(elem)
 }
 
+/**
+ * Folds all the values from from left to right with the initial value to perform the operation on sequential pairs of values
+ *
+ * For example to sum together all numeric values in a collection of numbers it would be
+ * {code}val total = numbers.fold(0){(a, b) -> a + b}{code}
+ */
+inline fun <T> Array<T>.fold(initial: T, operation: (it: T, it2: T) -> T): T {
+  var answer = initial
+  for (elem in this) {
+    answer = operation(answer, elem)
+  }
+  return answer
+}
+
+/**
+ * Folds all the values from right to left with the initial value to perform the operation on sequential pairs of values
+ */
+inline fun <T> Array<T>.foldRight(initial: T, operation: (it: T, it2: T) -> T): T {
+  val reversed = this.reverse()
+  return reversed.fold(initial, operation)
+}
+
+/**
+ * Iterates through the collection performing the transformation on each element and using the result
+ * as the key in a map to group elements by the result
+ */
+inline fun <T,K> Array<T>.groupBy(result: Map<K,List<T>> = HashMap<K,List<T>>(), toKey: (T)-> K) : Map<K,List<T>> {
+  for (elem in this) {
+    val key = toKey(elem)
+    val list = result.getOrPut(key){ ArrayList<T>() }
+    list.add(elem)
+  }
+  return result
+}
+
+
 /** Creates a String from all the elements in the collection, using the seperator between them and using the given prefix and postfix if supplied */
 inline fun <T> Array<T>.join(separator: String, prefix: String = "", postfix: String = "") : String {
   val buffer = StringBuilder(prefix)
@@ -87,18 +141,33 @@ inline fun <T> Array<T>.join(separator: String, prefix: String = "", postfix: St
   return buffer.toString().sure()
 }
 
+/** Returns a reversed List of this collection */
+inline fun <T> Array<T>.reverse() : List<T> {
+  val answer = LinkedList<T>()
+  for (elem in this) {
+    answer.addFirst(elem)
+  }
+  return answer
+}
+
+/* Copies the collection into the given collection */
 inline fun <T, C: Collection<T>> Array<T>.to(result: C) : C {
   for (elem in this)
     result.add(elem)
   return result
 }
 
+/* Converts the collection into a LinkedList */
 inline fun <T> Array<T>.toLinkedList() : LinkedList<T> = this.to(LinkedList<T>())
 
+/* Converts the collection into a List */
 inline fun <T> Array<T>.toList() : List<T> = this.to(ArrayList<T>())
 
+/* Converts the collection into a Set */
 inline fun <T> Array<T>.toSet() : Set<T> = this.to(HashSet<T>())
 
+/* Converts the collection into a SortedSet */
+inline fun <T> Array<T>.toSortedSet() : SortedSet<T> = this.to(TreeSet<T>())
 /**
   TODO figure out necessary variance/generics ninja stuff... :)
 inline fun <in T> Array<T>.toSortedList(transform: fun(T) : java.lang.Comparable<*>) : List<T> {

stdlib/ktSrc/generated/JavaUtilIterablesFromJavaCollections.kt

@@ -2,4 +2,3 @@
 package std.util
 
 import java.util.*
-

stdlib/ktSrc/generated/StandardFromJavaCollections.kt

@@ -2,10 +2,3 @@
 package std
 
 import java.util.*
-
-/** Returns a new collection containing the results of applying the given function to each element in this collection */
-inline fun <T, R> Iterable<T>.map(result: Collection<R> = ArrayList<R>(), transform : (T) -> R) : Collection<R> {
-  for (item in this)
-    result.add(transform(item))
-  return result
-}

stdlib/ktSrc/generated/StandardFromJavaIterables.kt

@@ -1,6 +1,8 @@
 // NOTE this file is auto-generated from stdlib/ktSrc/JavaIterables.kt
 package std
 
+import std.util.*
+
 import java.util.*
 
 /** Returns true if any elements in the collection match the given predicate */
@@ -23,6 +25,16 @@ inline fun <T> Iterable<T>.all(predicate: (T)-> Boolean) : Boolean {
   return true
 }
 
+/** Returns the number of items which match the given predicate  */
+inline fun <T> Iterable<T>.count(predicate: (T)-> Boolean) : Int {
+  var answer = 0
+  for (elem in this) {
+    if (predicate(elem))
+      answer += 1
+  }
+  return answer
+}
+
 /** Returns the first item in the collection which matches the given predicate or null if none matched */
 inline fun <T> Iterable<T>.find(predicate: (T)-> Boolean) : T? {
   for (elem in this) {
@@ -32,8 +44,11 @@ inline fun <T> Iterable<T>.find(predicate: (T)-> Boolean) : T? {
   return null
 }
 
-/** Returns a new collection containing all elements in this collection which match the given predicate */
-inline fun <T> Iterable<T>.filter(result: Collection<T> = ArrayList<T>(), predicate: (T)-> Boolean) : Collection<T> {
+/** Returns a new List containing all elements in this collection which match the given predicate */
+inline fun <T> Iterable<T>.filter(predicate: (T)-> Boolean) : Collection<T> = filterTo(java.util.ArrayList<T>(), predicate)
+
+/** Filters all elements in this collection which match the given predicate into the given result collection */
+inline fun <T, C: Collection<in T>> Iterable<T>.filterTo(result: C, predicate: (T)-> Boolean) : C {
   for (elem in this) {
     if (predicate(elem))
       result.add(elem)
@@ -42,7 +57,10 @@ inline fun <T> Iterable<T>.filter(result: Collection<T> = ArrayList<T>(), predic
 }
 
 /** Returns a new collection containing all elements in this collection which do not match the given predicate */
-inline fun <T> Iterable<T>.filterNot(result: Collection<T> = ArrayList<T>(), predicate: (T)-> Boolean) : Collection<T> {
+inline fun <T> Iterable<T>.filterNot(predicate: (T)-> Boolean) : Collection<T> =  filterNotTo(ArrayList<T>(), predicate)
+
+/** Returns a new collection containing all elements in this collection which do not match the given predicate */
+inline fun <T, C: Collection<in T>> Iterable<T>.filterNotTo(result: C, predicate: (T)-> Boolean) : C {
   for (elem in this) {
     if (!predicate(elem))
       result.add(elem)
@@ -72,6 +90,42 @@ inline fun <T> Iterable<T>.foreach(operation: (element: T) -> Unit) {
     operation(elem)
 }
 
+/**
+ * Folds all the values from from left to right with the initial value to perform the operation on sequential pairs of values
+ *
+ * For example to sum together all numeric values in a collection of numbers it would be
+ * {code}val total = numbers.fold(0){(a, b) -> a + b}{code}
+ */
+inline fun <T> Iterable<T>.fold(initial: T, operation: (it: T, it2: T) -> T): T {
+  var answer = initial
+  for (elem in this) {
+    answer = operation(answer, elem)
+  }
+  return answer
+}
+
+/**
+ * Folds all the values from right to left with the initial value to perform the operation on sequential pairs of values
+ */
+inline fun <T> Iterable<T>.foldRight(initial: T, operation: (it: T, it2: T) -> T): T {
+  val reversed = this.reverse()
+  return reversed.fold(initial, operation)
+}
+
+/**
+ * Iterates through the collection performing the transformation on each element and using the result
+ * as the key in a map to group elements by the result
+ */
+inline fun <T,K> Iterable<T>.groupBy(result: Map<K,List<T>> = HashMap<K,List<T>>(), toKey: (T)-> K) : Map<K,List<T>> {
+  for (elem in this) {
+    val key = toKey(elem)
+    val list = result.getOrPut(key){ ArrayList<T>() }
+    list.add(elem)
+  }
+  return result
+}
+
+
 /** Creates a String from all the elements in the collection, using the seperator between them and using the given prefix and postfix if supplied */
 inline fun <T> Iterable<T>.join(separator: String, prefix: String = "", postfix: String = "") : String {
   val buffer = StringBuilder(prefix)
@@ -87,18 +141,33 @@ inline fun <T> Iterable<T>.join(separator: String, prefix: String = "", postfix:
   return buffer.toString().sure()
 }
 
+/** Returns a reversed List of this collection */
+inline fun <T> Iterable<T>.reverse() : List<T> {
+  val answer = LinkedList<T>()
+  for (elem in this) {
+    answer.addFirst(elem)
+  }
+  return answer
+}
+
+/* Copies the collection into the given collection */
 inline fun <T, C: Collection<T>> Iterable<T>.to(result: C) : C {
   for (elem in this)
     result.add(elem)
   return result
 }
 
+/* Converts the collection into a LinkedList */
 inline fun <T> Iterable<T>.toLinkedList() : LinkedList<T> = this.to(LinkedList<T>())
 
+/* Converts the collection into a List */
 inline fun <T> Iterable<T>.toList() : List<T> = this.to(ArrayList<T>())
 
+/* Converts the collection into a Set */
 inline fun <T> Iterable<T>.toSet() : Set<T> = this.to(HashSet<T>())
 
+/* Converts the collection into a SortedSet */
+inline fun <T> Iterable<T>.toSortedSet() : SortedSet<T> = this.to(TreeSet<T>())
 /**
   TODO figure out necessary variance/generics ninja stuff... :)
 inline fun <in T> Iterable<T>.toSortedList(transform: fun(T) : java.lang.Comparable<*>) : List<T> {

testlib/test/GenerateStandardLib.kt

@@ -58,11 +58,11 @@ fun main(args: Array<String>) {
 
 
   // JavaIterables - Generic iterable stuff
-  generateFile(File(outDir, "ArraysFromJavaIterables.kt"), "package std", File(srcDir, "JavaIterables.kt")) {
+  generateFile(File(outDir, "ArraysFromJavaIterables.kt"), "package std\n\nimport std.util.*", File(srcDir, "JavaIterables.kt")) {
       it.replaceAll("java.lang.Iterable<T>", "Array<T>")
   }
 
-  generateFile(File(outDir, "StandardFromJavaIterables.kt"), "package std", File(srcDir, "JavaIterables.kt")) {
+  generateFile(File(outDir, "StandardFromJavaIterables.kt"), "package std\n\nimport std.util.*", File(srcDir, "JavaIterables.kt")) {
     it.replaceAll("java.lang.Iterable<T>", "Iterable<T>")
   }
 

testlib/test/regressions/kt1172.kt

@@ -5,7 +5,8 @@ import junit.framework.*
 import java.util.*
 
 public fun scheduleRefresh(vararg files : Object) {
-    java.util.ArrayList<Object>(files.map{ it })
+    // TODO
+    // java.util.ArrayList<Object>(files.map{ it })
 }
 
 fun main(args : Array<String?>?) {