add failure wall command '--'

main/CommandSupport.scala

@@ -160,6 +160,8 @@ CompileSyntax + """
 	Compiled classes will be written to the 'classes' directory.
 	Cached information about the compilation will be written to 'cache'.
 """
+
+	val FailureWall = "--"
 	
 	def Load = "load"
 	def LoadLabel = "a project"

main/Main.scala

@@ -61,9 +61,13 @@ class xMain extends xsbti.AppMain
 import CommandSupport._
 object Commands
 {
-	def DefaultCommands = Seq(help, reload, read, history, exit, load, loadCommands, compile, discover,
+	def DefaultCommands = Seq(ignore, help, reload, read, history, exit, load, loadCommands, compile, discover,
 		projects, project, setOnFailure, ifLast, multi, shell, alias, append, act)
 
+	def ignore = nothing(Set(FailureWall))
+
+	def nothing(ignore: Set[String]) = Command.univ { s => Apply(){ case in if ignore(in.line) => s } }
+
 	def applicable(state: State): Stream[Apply] =
 		state.processors.toStream.flatMap(_.applies(state) )
 

main/State.scala

@@ -3,7 +3,8 @@
  */
 package sbt
 
-import java.io.File
+	import java.io.File
+	import CommandSupport.FailureWall
 
 case class State(project: Any)(
 	val configuration: xsbti.AppConfiguration,
@@ -50,10 +51,18 @@ object State
 		def get[T](key: AttributeKey[T]) = s.attributes.get(key)
 		def put[T](key: AttributeKey[T], value: T) = s.copy()(attributes = s.attributes.put(key, value))
 		def fail =
-			s.onFailure match
+		{
+			val remaining = s.commands.dropWhile(_ != FailureWall)
+			if(remaining.isEmpty)
 			{
-				case Some(c) => s.copy()(commands = c :: Nil, onFailure = None)
-				case None => exit(ok = false)
+				s.onFailure match
+				{
+					case Some(c) => s.copy()(commands = c :: Nil, onFailure = None)
+					case None => exit(ok = false)
+				}
 			}
+			else
+				s.copy()(commands = remaining)
+		}
 	}
 }