propagated Stream.flatMap and Android examples

3 files changed, 59 insertions, 33 deletions

diff --git a/build.xml b/build.xml
index e8dc3d1228..a46ea7a7bd 100644
--- a/build.xml
+++ b/build.xml
@@ -820,8 +820,6 @@ CLDC
 ANDROID
 ============================================================================ -->
 
-  <property name="dx.jar" value="${android.home}/tools/lib/dx.jar"/>
-
   <target name="android.sources"
           description="Create the source directory for Android library"
   >
@@ -843,7 +841,7 @@ ANDROID
     </copy>
   </target>
 
-  <target name="android.libraries" 
+  <target name="android.libraries"
           depends="setup.quick, android.sources"
           description="Builds the Scala library for Android">
     <fail message="Android home is not set or could not find android.jar in ${android.home}">
@@ -897,9 +895,9 @@ ANDROID
     </quick>
   </target>
 
-  <target name="android" depends="android.libraries"
+  <target name="android.build" depends="android.libraries"
           description="Convert this project's .class files into .dex files">
-    <java jar="${dx.jar}" fork="true" failonerror="true">
+     <java jar="${dx.jar}" fork="true" failonerror="true">
       <jvmarg value="-Djava.ext.dirs=${android.home}${file.separator}tools${file.separator}lib"/>
       <jvmarg value="-Xmx384M"/>
       <arg value="--dex"/>
@@ -918,7 +916,22 @@ ANDROID
       basedir="${android.dir}/lib/library"
       includes="scala/**/*.class"
     />
-    <!-- examples ? -->
+  </target>
+
+  <target name="android" depends="init">
+    <condition property="android.supported">
+      <and>
+        <not><contains string="${java.version}" substring="1.4"/></not>
+        <contains string="${java.vendor}" substring="Sun"/>
+      </and>
+    </condition>
+    <if><isset property="android.supported"/><then>
+      <antcall target="android.build">
+        <param name="dx.jar" value="${android.home}/tools/lib/dx.jar"/>
+      </antcall>
+    </then><else>
+      <echo message="The Android library build requires Sun Java 1.5 or newer"/>
+    </else></if>
   </target>
 
 <!-- ===========================================================================
@@ -1751,7 +1764,7 @@ GENERATES A DISTRIBUTION
       <libset dir="${dist.current.dir}/lib" includes="${lib.jar.name},${dbc.jar.name}"/>
       <srcset dir="${dist.current.dir}/lib" includes="${libsrc.jar.name},${dbcsrc.jar.name}"/>
     </quicksbaz>
-  <!-- Create the Scala developper package -->
+  <!-- Create the Scala developer package -->
     <quicksbaz
       file="${dist.dir}/scala-devel-${version.number}.sbp"
       adfile="${dist.dir}/scala-devel-${version.number}.advert"
@@ -1812,15 +1825,23 @@ GENERATES A DISTRIBUTION
       <libset dir="${cldc.dir}/lib" includes="*.jar"/>
     </quicksbaz>
   <!-- Creates the Android package -->
-    <quicksbaz
-      file="${dist.dir}/scala-android-${version.number}.sbp"
-      adfile="${dist.dir}/scala-android-${version.number}.advert"
-      name="scala-android"
-      version="${version.number}"
-      desc="The Scala Android package contains everything needed to use Scala on Android."
-      link="${sbaz.universe}/scala-android-${version.number}.sbp">
-      <libset dir="${android.dir}/lib" includes="*.jar"/>
-    </quicksbaz>
+    <if><isset property="android.supported"/><then>
+      <copy todir="${dist.current.dir}/doc/scala-android/examples">
+        <fileset dir="${docs.dir}/android-examples">
+          <exclude name="**/R.java"/>
+        </fileset>
+      </copy>
+      <quicksbaz
+        file="${dist.dir}/scala-android-${version.number}.sbp"
+        adfile="${dist.dir}/scala-android-${version.number}.advert"
+        name="scala-android"
+        version="${version.number}"
+        desc="The Scala Android package contains everything needed to use Scala on Android."
+        link="${sbaz.universe}/scala-android-${version.number}.sbp">
+        <libset dir="${android.dir}/lib" includes="*.jar"/>
+        <docset dir="${dist.current.dir}/doc/scala-android" includes="**"/>
+      </quicksbaz>
+    </then></if>
   </target>
 
   <target name="build.archive" depends="build.dist">
diff --git a/src/library/scala/Stream.scala b/src/library/scala/Stream.scala
index a771e1d217..1415e3ad06 100644
--- a/src/library/scala/Stream.scala
+++ b/src/library/scala/Stream.scala
@@ -58,7 +58,7 @@ object Stream {
       }
     }
 
-    def unapply[A](str: Stream[A]): Option[(A,Stream[A])] =
+    def unapply[A](str: Stream[A]): Option[(A, Stream[A])] =
       if(str.isEmpty)
         None
       else
@@ -113,7 +113,7 @@ object Stream {
   def range(start: Int, end: Int, step: Int): Stream[Int] = {
     def loop(lo: Int): Stream[Int] =
       if (lo >= end) empty
-      else cons(lo, loop(lo + step));
+      else cons(lo, loop(lo + step))
     loop(start)
   }
 
@@ -131,7 +131,7 @@ object Stream {
   def range(start: Int, end: Int, step: Int => Int): Stream[Int] = {
     def loop(lo: Int): Stream[Int] =
       if (lo >= end) empty
-      else cons(lo, loop(step(lo)));
+      else cons(lo, loop(step(lo)))
     loop(start)
   }
 
@@ -170,7 +170,7 @@ object Stream {
    *  @return     the stream composed of n elements all equal to elem
    */
   def make[A](n: Int, elem: A): Stream[A] =
-    Stream.const(elem).take(n)
+    Stream.const(elem) take n
 }
 
 /**
@@ -237,7 +237,7 @@ trait Stream[+A] extends Seq.Projection[A] {
    *  @param rest   The stream that gets appended to this stream
    */
   override def append[B >: A](rest: => Iterable[B]): Stream[B] =
-    if (isEmpty) rest.toStream else Stream.cons(head, tail.append(rest))
+    if (isEmpty) rest.toStream else Stream.cons(head, tail append rest)
 
 
   /** An iterator returning the elements of this stream one by one.
@@ -288,7 +288,7 @@ trait Stream[+A] extends Seq.Projection[A] {
    */
   override def take(n: Int): Stream[A] =
     if (isEmpty || n <= 0) Stream.empty
-    else Stream.cons(head, tail.take(n-1))
+    else Stream.cons(head, tail take (n-1))
 
   /** Returns the stream without its <code>n</code> first elements.
    *  If the stream has less than <code>n</code> elements, the empty stream is returned.
@@ -313,7 +313,7 @@ trait Stream[+A] extends Seq.Projection[A] {
    */
   override def takeWhile(p: A => Boolean): Stream[A] =
     if (isEmpty || !p(head)) Stream.empty
-    else Stream.cons(head, tail.takeWhile(p))
+    else Stream.cons(head, tail takeWhile p)
 
   /** Returns the longest suffix of this stream whose first element
    *  does not satisfy the predicate <code>p</code>.
@@ -337,7 +337,7 @@ trait Stream[+A] extends Seq.Projection[A] {
    */
   override def map[B](f: A => B): Stream[B] =
     if (isEmpty) Stream.empty
-    else Stream.cons(f(head), tail.map(f))
+    else Stream.cons(f(head), tail map f)
 
   /** Apply the given function <code>f</code> to each element of this stream
    *  (while respecting the order of the elements).
@@ -374,11 +374,10 @@ trait Stream[+A] extends Seq.Projection[A] {
    *           predicate <code>p</code>.
    */
   override def forall(p: A => Boolean): Boolean = {
-    def loop(s: Stream[A]): Boolean = {
+    def loop(s: Stream[A]): Boolean =
       if (s.isEmpty) true
       else if (p(s.head)) loop(s.tail)
       else false
-    }
     loop(this)
   }
 
@@ -390,11 +389,10 @@ trait Stream[+A] extends Seq.Projection[A] {
    *           satisfies the predicate <code>p</code>.
    */
   override def exists(p: A => Boolean): Boolean = {
-    def loop(s: Stream[A]): Boolean = {
+    def loop(s: Stream[A]): Boolean =
       if (s.isEmpty) false
       else if (p(s.head)) true
       else loop(s.tail)
-    }
     loop(this)
   }
 
@@ -433,7 +431,14 @@ trait Stream[+A] extends Seq.Projection[A] {
    */
   override def flatMap[B](f: A => Iterable[B]): Stream[B] =
     if (isEmpty) Stream.empty
-    else Stream.fromIterator(f(head).elements) append (tail flatMap f)
+    else {
+      val s: Stream[B] = f(head) match {
+        case x: Stream[_] => x
+        case y: List[_]   => y.toStream
+        case z            => z.toList.toStream
+      }
+      s append (tail flatMap f)
+    }
 
   override def toStream = this
 
@@ -466,9 +471,9 @@ trait Stream[+A] extends Seq.Projection[A] {
    *              <code>Stream(a<sub>0</sub>, ..., a<sub>m</sub>)
    *              zip Stream(b<sub>0</sub>, ..., b<sub>n</sub>)</code> is invoked.
    */
-  def zip[B](that: Stream[B]): Stream[Tuple2[A, B]] =
+  def zip[B](that: Stream[B]): Stream[(A, B)] =
     if (this.isEmpty || that.isEmpty) Stream.empty
-    else Stream.cons(Tuple2(this.head, that.head), this.tail.zip(that.tail))
+    else Stream.cons((this.head, that.head), this.tail zip that.tail)
 
 
   /** Returns a stream that pairs each element of this stream
@@ -477,7 +482,7 @@ trait Stream[+A] extends Seq.Projection[A] {
    *  @return      the stream <code>Stream({a<sub>0</sub>,0}, {a<sub>0</sub>,1},...)</code>
    *               where <code>a<sub>i</sub></code> are the elements of this stream.
    */
-  def zipWithIndex: Stream[Tuple2[A, Int]] =
+  def zipWithIndex: Stream[(A, Int)] =
     zip(Stream.from(0))
 
   /** Prints elements of this stream one by one, separated by commas */
diff --git a/test/files/run/streams.scala b/test/files/run/streams.scala
index 1844fdb6ab..19bb9c943d 100644
--- a/test/files/run/streams.scala
+++ b/test/files/run/streams.scala
@@ -22,7 +22,7 @@ object Test extends Application {
   println(s2.dropWhile(_ > 0))
   println
 
-  val s3 = Stream.range(1, 100000)
+  val s3 = Stream.range(1, 100000) // ticket #153: Stackoverflow
   println(s3.length)
 
   // ticket #153