Added a :type command to the repl, no review.

1 files changed, 9 insertions, 1 deletions

diff --git a/src/compiler/scala/tools/nsc/interpreter/ILoop.scala b/src/compiler/scala/tools/nsc/interpreter/ILoop.scala
index 53a3448c20..3d4ff7a20b 100644
--- a/src/compiler/scala/tools/nsc/interpreter/ILoop.scala
+++ b/src/compiler/scala/tools/nsc/interpreter/ILoop.scala
@@ -216,7 +216,8 @@ class ILoop(in0: Option[BufferedReader], protected val out: PrintWriter)
        NoArgs("quit", "exit the interpreter", () => Result(false, None)),
        NoArgs("replay", "reset execution and replay all previous commands", replay),
        LineArg("sh", "fork a shell and run a command", shCommand),
-       NoArgs("silent", "disable/enable automatic printing of results", verbosity)
+       NoArgs("silent", "disable/enable automatic printing of results", verbosity),
+       LineArg("type", "display the type of an expression without evaluating it", typeCommand)
     )
   }
 
@@ -315,6 +316,13 @@ class ILoop(in0: Option[BufferedReader], protected val out: PrintWriter)
     }
   }
 
+  private def typeCommand(line: String): Result = {
+    intp.typeOfExpression(line) match {
+      case Some(tp) => tp.toString
+      case _        => "Failed to determine type."
+    }
+  }
+
   private def javapCommand(line: String): Result = {
     if (line == "")
       return ":javap [-lcsvp] [path1 path2 ...]"