Aladdin - Scala Bugtracking

	[#834]	project: compiler	priority: medium	category: bug
	submitter	assigned to	status	date submitted
	Lex	Martin	fixed	2006-11-24 14:58:13.0
subject	return in a closure in a method in a method
code	object Test { def response: String = { def check: Option[String] = { val closure: String=>Nothing = p => return Some("deep return") // should return from check closure("whatever") } check return "ok" } def main(args: Array[String]) { Console.println(response) } }
what happened	exception when traversing def check: scala.Option[java.lang.String] = { val closure: (java.lang.String) => scala.Nothing = ((p: java.lang.String) => return new scala.Some[java.lang.S\ tring]("deep return")); closure.apply("whatever") } exception when traversing { def check: scala.Option[java.lang.String] = { val closure: (java.lang.String) => scala.Nothing = ((p: java.lang.String) => return new scala.Some[java.lang\ .String]("deep return")); closure.apply("whatever") }; check; return "ok" } exception when traversing def response: java.lang.String = { def check: scala.Option[java.lang.String] = { val closure: (java.lang.String) => scala.Nothing = ((p: java.lang.String) => return new scala.Some[java.lang\ .String]("deep return")); closure.apply("whatever") }; check; return "ok" } exception when traversing java.lang.Object with scala.ScalaObject { def this(): object Test = { Test.super.this(); () }; def response: java.lang.String = { def check: scala.Option[java.lang.String] = { val closure: (java.lang.String) => scala.Nothing = ((p: java.lang.String) => return new scala.Some[java.la\ ng.String]("deep return")); closure.apply("whatever") }; check; return "ok" }; def main(args: scala.Array[java.lang.String]): scala.Unit = scala.Console.println(Test.this.response) } exception when traversing final class Test extends java.lang.Object with scala.ScalaObject { def this(): object Test = { Test.super.this(); () }; def response: java.lang.String = { def check: scala.Option[java.lang.String] = { val closure: (java.lang.String) => scala.Nothing = ((p: java.lang.String) => return new scala.Some[java.la\ ng.String]("deep return")); closure.apply("whatever") }; check; return "ok" }; def main(args: scala.Array[java.lang.String]): scala.Unit = scala.Console.println(Test.this.response) } exception when traversing package { final class Test extends java.lang.Object with scala.ScalaObject { def this(): object Test = { Test.super.this(); () }; def response: java.lang.String = { def check: scala.Option[java.lang.String] = { val closure: (java.lang.String) => scala.Nothing = ((p: java.lang.String) => return new scala.Some[java.\ lang.String]("deep return")); closure.apply("whatever") }; check; return "ok" }; def main(args: scala.Array[java.lang.String]): scala.Unit = scala.Console.println(Test.this.response) } } Exception in thread "main" scala.tools.nsc.symtab.Types$TypeError: type _ escapes its defining scope as part of \ type _ at scala.tools.nsc.typechecker.Contexts$Context.error(Contexts.scala:252) at scala.tools.nsc.typechecker.Infer$Inferencer.error(Infer.scala:245) at scala.tools.nsc.typechecker.Typers$Typer$checkNoEscaping$.check(Typers.scala:338) at scala.tools.nsc.typechecker.Typers$Typer$checkNoEscaping$.locals(Typers.scala:318) at scala.tools.nsc.typechecker.Typers$Typer.typedCase(Typers.scala:1164) at scala.tools.nsc.typechecker.Typers$Typer$$anonfun$39.apply(Typers.scala:1171) at scala.tools.nsc.typechecker.Typers$Typer$$anonfun$39.apply(Typers.scala:1170) at scala.List$.loop$0(List.scala:244) at scala.List$.mapConserve(List.scala:261) at scala.tools.nsc.typechecker.Typers$Typer.typedCases(Typers.scala:1170) at scala.tools.nsc.typechecker.Typers$Typer.typed1(Typers.scala:1998) at scala.tools.nsc.typechecker.Typers$Typer.typed(Typers.scala:2221) at scala.tools.nsc.typechecker.Typers$Typer.typedBlock(Typers.scala:1131) at scala.tools.nsc.typechecker.Typers$Typer.typed1(Typers.scala:1878) at scala.tools.nsc.typechecker.Typers$Typer.typed(Typers.scala:2221) at scala.tools.nsc.typechecker.Typers$Typer.typed(Typers.scala:2253) at scala.tools.nsc.transform.UnCurry$UnCurryTransformer.scala$tools$nsc$transform$UnCurry$UnCurryTransformer$$n\ onLocalReturnTry(UnCurry.scala:170) at scala.tools.nsc.transform.UnCurry$UnCurryTransformer$$anonfun$17.apply(UnCurry.scala:437) at scala.tools.nsc.transform.UnCurry$UnCurryTransformer$$anonfun$17.apply(UnCurry.scala:423) at scala.tools.nsc.symtab.SymbolTable.atPhase(SymbolTable.scala:77) at scala.tools.nsc.transform.UnCurry$UnCurryTransformer.postTransform(UnCurry.scala:423) at scala.tools.nsc.transform.UnCurry$UnCurryTransformer.transform(UnCurry.scala:95) at scala.tools.nsc.ast.Trees$Transformer$$anonfun$30.apply(Trees.scala:1178) at scala.tools.nsc.ast.Trees$Transformer$$anonfun$30.apply(Trees.scala:1176) at scala.List$.loop$0(List.scala:244) at scala.List$.mapConserve(List.scala:261) at scala.tools.nsc.ast.Trees$Transformer.transformStats(Trees.scala:1176) at scala.tools.nsc.ast.Trees$Transformer.transform(Trees.scala:1098) at scala.tools.nsc.transform.TypingTransformers$TypingTransformer.transform(TypingTransformers.scala:46) at scala.tools.nsc.transform.UnCurry$UnCurryTransformer.mainTransform(UnCurry.scala:415) at scala.tools.nsc.transform.UnCurry$UnCurryTransformer.transform(UnCurry.scala:95) at scala.tools.nsc.ast.Trees$Transformer$$anonfun$20.apply(Trees.scala:1077) at scala.tools.nsc.ast.Trees$Transformer$$anonfun$20.apply(Trees.scala:1076) at scala.tools.nsc.ast.Trees$Transformer.atOwner(Trees.scala:1184) at scala.tools.nsc.transform.TypingTransformers$TypingTransformer.atOwner(TypingTransformers.scala:33) at scala.tools.nsc.transform.TypingTransformers$TypingTransformer.atOwner(TypingTransformers.scala:27) at scala.tools.nsc.ast.Trees$Transformer.transform(Trees.scala:1075) at scala.tools.nsc.transform.TypingTransformers$TypingTransformer.transform(TypingTransformers.scala:46) at scala.tools.nsc.transform.UnCurry$UnCurryTransformer.scala$tools$nsc$transform$UnCurry$UnCurryTransformer$$s\ uper$transform(UnCurry.scala:345) at scala.tools.nsc.transform.UnCurry$UnCurryTransformer$$anonfun$5.apply(UnCurry.scala:345) at scala.tools.nsc.transform.UnCurry$UnCurryTransformer$$anonfun$5.apply(UnCurry.scala:329) at scala.tools.nsc.transform.UnCurry$UnCurryTransformer.withNeedLift$0(UnCurry.scala:313) at scala.tools.nsc.transform.UnCurry$UnCurryTransformer.mainTransform(UnCurry.scala:328) at scala.tools.nsc.transform.UnCurry$UnCurryTransformer.transform(UnCurry.scala:95) at scala.tools.nsc.ast.Trees$Transformer$$anonfun$30.apply(Trees.scala:1178) at scala.tools.nsc.ast.Trees$Transformer$$anonfun$30.apply(Trees.scala:1176) at scala.List$.loop$0(List.scala:244) at scala.List$.mapConserve(List.scala:261) at scala.List$.loop$0(List.scala:248) at scala.List$.mapConserve(List.scala:261) at scala.tools.nsc.ast.Trees$Transformer.transformStats(Trees.scala:1176) at scala.tools.nsc.ast.Trees$Transformer.transform(Trees.scala:1096) at scala.tools.nsc.transform.TypingTransformers$TypingTransformer.scala$tools$nsc$transform$TypingTransformers$\ TypingTransformer$$super$transform(TypingTransformers.scala:44) at scala.tools.nsc.transform.TypingTransformers$TypingTransformer$$anonfun$0.apply(TypingTransformers.scala:44)\ at scala.tools.nsc.transform.TypingTransformers$TypingTransformer$$anonfun$0.apply(TypingTransformers.scala:44)\ at scala.tools.nsc.ast.Trees$Transformer.atOwner(Trees.scala:1184) at scala.tools.nsc.transform.TypingTransformers$TypingTransformer.atOwner(TypingTransformers.scala:33) at scala.tools.nsc.transform.TypingTransformers$TypingTransformer.atOwner(TypingTransformers.scala:27) at scala.tools.nsc.transform.TypingTransformers$TypingTransformer.transform(TypingTransformers.scala:44) at scala.tools.nsc.transform.UnCurry$UnCurryTransformer.scala$tools$nsc$transform$UnCurry$UnCurryTransformer$$s\ uper$transform(UnCurry.scala:345) at scala.tools.nsc.transform.UnCurry$UnCurryTransformer$$anonfun$16.apply(UnCurry.scala:412) at scala.tools.nsc.transform.UnCurry$UnCurryTransformer$$anonfun$16.apply(UnCurry.scala:412) at scala.tools.nsc.transform.UnCurry$UnCurryTransformer.withInConstructorFlag$0(UnCurry.scala:321) at scala.tools.nsc.transform.UnCurry$UnCurryTransformer.mainTransform(UnCurry.scala:412) at scala.tools.nsc.transform.UnCurry$UnCurryTransformer.transform(UnCurry.scala:95) at scala.tools.nsc.ast.Trees$Transformer.transformTemplate(Trees.scala:1164) at scala.tools.nsc.ast.Trees$Transformer$$anonfun$17.apply(Trees.scala:1064) at scala.tools.nsc.ast.Trees$Transformer$$anonfun$17.apply(Trees.scala:1063) at scala.tools.nsc.ast.Trees$Transformer.atOwner(Trees.scala:1184) at scala.tools.nsc.transform.TypingTransformers$TypingTransformer.atOwner(TypingTransformers.scala:33) at scala.tools.nsc.transform.TypingTransformers$TypingTransformer.atOwner(TypingTransformers.scala:27) at scala.tools.nsc.ast.Trees$Transformer.transform(Trees.scala:1062) at scala.tools.nsc.transform.TypingTransformers$TypingTransformer.transform(TypingTransformers.scala:46) at scala.tools.nsc.transform.UnCurry$UnCurryTransformer.mainTransform(UnCurry.scala:415) at scala.tools.nsc.transform.UnCurry$UnCurryTransformer.transform(UnCurry.scala:95) at scala.tools.nsc.ast.Trees$Transformer$$anonfun$30.apply(Trees.scala:1178) at scala.tools.nsc.ast.Trees$Transformer$$anonfun$30.apply(Trees.scala:1176) at scala.List$.loop$0(List.scala:244) at scala.List$.mapConserve(List.scala:261) at scala.tools.nsc.ast.Trees$Transformer.transformStats(Trees.scala:1176) at scala.tools.nsc.ast.Trees$Transformer$$anonfun$16.apply(Trees.scala:1059) at scala.tools.nsc.ast.Trees$Transformer$$anonfun$16.apply(Trees.scala:1059) at scala.tools.nsc.ast.Trees$Transformer.atOwner(Trees.scala:1184) at scala.tools.nsc.transform.TypingTransformers$TypingTransformer.atOwner(TypingTransformers.scala:33) at scala.tools.nsc.transform.TypingTransformers$TypingTransformer.atOwner(TypingTransformers.scala:27) at scala.tools.nsc.ast.Trees$Transformer.transform(Trees.scala:1058) at scala.tools.nsc.transform.TypingTransformers$TypingTransformer.transform(TypingTransformers.scala:46) at scala.tools.nsc.transform.UnCurry$UnCurryTransformer.mainTransform(UnCurry.scala:415) at scala.tools.nsc.transform.UnCurry$UnCurryTransformer.transform(UnCurry.scala:95) at scala.tools.nsc.ast.Trees$Transformer.transformUnit(Trees.scala:1179) at scala.tools.nsc.transform.Transform$Phase.apply(Transform.scala:30) at scala.tools.nsc.Global$GlobalPhase.applyPhase(Global.scala:220) at scala.tools.nsc.Global$GlobalPhase$$anonfun$1.apply(Global.scala:209) at scala.tools.nsc.Global$GlobalPhase$$anonfun$1.apply(Global.scala:209) at scala.Iterator$class.foreach(Iterator.scala:341) at scala.collection.mutable.ListBuffer$$anon$0.foreach(ListBuffer.scala:244) at scala.tools.nsc.Global$GlobalPhase.run(Global.scala:209) at scala.tools.nsc.Global$Run.compileSources(Global.scala:475) at scala.tools.nsc.Global$Run.compile(Global.scala:547) at scala.tools.nsc.Main$.process(Main.scala:74) at scala.tools.nsc.Main$.main(Main.scala:96) at scala.tools.nsc.Main.main(Main.scala)
what expected	This should compile and print "deep return"
[back to overview]

Changes of this bug report

Lex edited on 2006-11-24 14:58:45.0

Lex edited on 2006-11-24 15:01:55.0

Err, actually, this should print "ok", not "deep return". Anyway, this return should be allowed.

Martin edited on 2006-11-27 15:15:21.0

The change in typed patterns triggered this, so this would probably affect all non-local returns, not just deep ones :-(