An option for real repl output.

There have been many requests to expose the products of
the repl in some way outside in-memory. This does that.

  scala                        # usual in-memory behavior
  scala -Yrepl-outdir ""       # make up a temp dir
  scala -Yrepl-outdir /foo/bar # use /foo/bar

1 files changed, 48 insertions, 0 deletions

diff --git a/src/compiler/scala/tools/nsc/interpreter/ReplDir.scala b/src/compiler/scala/tools/nsc/interpreter/ReplDir.scala
new file mode 100644
index 0000000000..9fbf64acb5
--- /dev/null
+++ b/src/compiler/scala/tools/nsc/interpreter/ReplDir.scala
@@ -0,0 +1,48 @@
+/* NSC -- new Scala compiler
+ * Copyright 2005-2012 LAMP/EPFL
+ * @author  Paul Phillips
+ */
+
+package scala.tools.nsc
+package interpreter
+
+import io.VirtualDirectory
+import settings.MutableSettings
+import scala.reflect.io.{ AbstractFile, PlainDirectory, Directory }
+import scala.collection.generic.Clearable
+
+/** Directory to save .class files to. */
+trait ReplDir extends AbstractFile with Clearable { }
+
+private class ReplVirtualDir() extends VirtualDirectory("(memory)", None) with ReplDir { }
+private class ReplRealDir(dir: Directory) extends PlainDirectory(dir) with ReplDir {
+  def clear() = {
+    dir.deleteRecursively()
+    dir.createDirectory()
+  }
+}
+
+class ReplOutput(val dirSetting: MutableSettings#StringSetting) {
+  // outdir for generated classfiles - may be in-memory (the default),
+  // a generated temporary directory, or a specified outdir.
+  val dir: ReplDir = (
+    if (dirSetting.isDefault)
+      new ReplVirtualDir()
+    else if (dirSetting.value == "")
+      new ReplRealDir(Directory.makeTemp("repl"))
+    else
+      new ReplRealDir(Directory(dirSetting.value))
+  )
+
+  // print the contents hierarchically
+  def show(out: JPrintWriter) = {
+    def pp(root: AbstractFile, indentLevel: Int) {
+      val label = root.name
+      val spaces = "    " * indentLevel
+      out.println(spaces + label)
+      if (root.isDirectory)
+        root.toList sortBy (_.name) foreach (x => pp(x, indentLevel + 1))
+    }
+    pp(dir, 0)
+  }
+}