adding topic ($_) support for map, grep, first and each on Array (res…

…olves issue #97)
MoeOrganization · May 3, 2013 · 1f0e138 · 1f0e138 · prakashk · May 6, 2013
1 parent a64d265
commit 1f0e138
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Showing 2 changed files with 41 additions and 11 deletions.
diff --git a/src/main/scala/org/moe/runtime/nativeobjects/MoeArrayObject.scala b/src/main/scala/org/moe/runtime/nativeobjects/MoeArrayObject.scala
@@ -76,26 +76,51 @@ class MoeArrayObject(
     array.map(_.unboxToString.get).mkString(sep.unboxToString.get)
   )
 
-  def map (r: MoeRuntime, f: MoeCode): MoeArrayObject = r.NativeObjects.getArray(
-    array.map(i => f.execute(new MoeArguments(List(i)))) : _*
-  )
+  def map (r: MoeRuntime, f: MoeCode): MoeArrayObject = {
+    val result = array.map({
+      (i) => 
+        f.getDeclarationEnvironment.setCurrentTopic(i)
+        f.execute(new MoeArguments(List(i)))
+    })
+    f.getDeclarationEnvironment.clearCurrentTopic
+    r.NativeObjects.getArray(result : _*)
+  }
 
-  def grep (r: MoeRuntime, f: MoeCode): MoeArrayObject = r.NativeObjects.getArray(
-    array.filter(i => f.execute(new MoeArguments(List(i))).isTrue) : _*
-  )
+  def grep (r: MoeRuntime, f: MoeCode): MoeArrayObject = {
+    val result = array.filter({
+      (i) => 
+        f.getDeclarationEnvironment.setCurrentTopic(i)
+        f.execute(new MoeArguments(List(i))).isTrue
+    })
+    f.getDeclarationEnvironment.clearCurrentTopic
+    r.NativeObjects.getArray(result : _*)
+  }
 
   def each (r: MoeRuntime, f: MoeCode): MoeUndefObject = {
-    array.foreach({ i => f.execute(new MoeArguments(List(i))); ()})
+    array.foreach({
+      (i) => 
+        f.getDeclarationEnvironment.setCurrentTopic(i)
+        f.execute(new MoeArguments(List(i)))
+        ()
+    })
+    f.getDeclarationEnvironment.clearCurrentTopic
     r.NativeObjects.getUndef
   }
 
+  def first (r: MoeRuntime, f: MoeCode): MoeObject = {
+    val result = array.dropWhile({
+      (i) => 
+        f.getDeclarationEnvironment.setCurrentTopic(i)
+        f.execute(new MoeArguments(List(i))).isFalse
+    })
+    f.getDeclarationEnvironment.clearCurrentTopic
+    result.head
+  }
+
   def reduce (r: MoeRuntime, f: MoeCode, init: Option[MoeObject]): MoeObject = init match {
     case Some(init_val) => array.foldLeft(init_val)({ (a, b) => f.execute(new MoeArguments(List(a, b))) })
     case None           => array.reduceLeft        ({ (a, b) => f.execute(new MoeArguments(List(a, b))) })
-  }
-
-  def first (r: MoeRuntime, f: MoeCode): MoeObject = 
-    array.dropWhile(i => f.execute(new MoeArguments(List(i))).isFalse).head
+  }  
 
   def max (r: MoeRuntime): MoeIntObject = r.NativeObjects.getInt(
       array.map(i => i.unboxToInt.get).max

diff --git a/t/001-literals/007-arrays.t b/t/001-literals/007-arrays.t
@@ -61,13 +61,16 @@ use Test::More;
     is(@x.join(", "), "10, 5, 3, 1", '... got the expected value from &join($sep)');
 
     is_deeply(@x.map(-> ($x) { $x + 10 }), [ 20, 15, 13, 11 ], '... got the expected value from &map');
+    is_deeply(@x.map(-> { $_ + 10 }), [ 20, 15, 13, 11 ], '... got the expected value from &map using $_');
 
     is_deeply(@x.grep(-> ($x) { ($x % 2) == 0 }), [ 10 ], '... got the expected value from &grep');
+    is_deeply(@x.grep(-> { ($_ % 2) == 0 }), [ 10 ], '... got the expected value from &grep using $_');
 
     is(@x.reduce(-> ($a, $b) { $a + $b }), 19, '... got the exepected value from &reduce');
     is(@x.reduce(-> ($a, $b) { $a + $b }, 100), 119, '... got the exepected value from &reduce($init)');    
 
     is(@x.first(-> ($x) { $x > 5 }), 10, '... got the exepected value from &first');
+    is(@x.first(-> { $_ > 5 }), 10, '... got the exepected value from &first using $_');
 
     is(@x.max, 10, '... got the exepected value from &max');
     is(@x.min, 1,  '... got the exepected value from &min');
@@ -91,6 +94,8 @@ use Test::More;
     my @x = [ 'foo', 'bar', 'baz' ];
     is(@x.each(-> ($x) { $x.chop }), undef, '... got the exepected value from &each');
     is_deeply(@x, [ 'fo', 'ba', 'ba' ], '... the array has been changed');
+    is(@x.each(-> { $_.chop }), undef, '... got the exepected value from &each using $_');
+    is_deeply(@x, [ 'f', 'b', 'b' ], '... the array has been changed');
 }
 
 {