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* Merge pull request #2088 from retronym/ticket/6146James Iry2013-02-072-0/+61
|\ | | | | SI-6146 More accurate prefixes for sealed subtypes.
| * SI-6146 More accurate prefixes for sealed subtypes.Jason Zaugg2013-02-072-0/+61
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When analysing exhaustivity/reachability of type tests and equality tests, the pattern matcher must construct a set of sealed subtypes based on the prefix of the static type of and the set of sealed descendent symbols of that type. Previously, it was using `memberType` for this purpose. In simple cases, this is sufficient: scala> class C { class I1; object O { class I2 } }; object D extends C defined class C defined module D scala> typeOf[D.type] memberType typeOf[C#I1].typeSymbol res0: u.Type = D.I1 But, as reported in this bug, it fails when there is an additional level of nesting: scala> typeOf[D.type] memberType typeOf[c.O.I2 forSome { val c: C }].typeSymbol res5: u.Type = C.O.I2 This commit introduces `nestedMemberType`, which uses `memberType` recursively up the prefix chain prefix chain. scala> nestedMemberType(typeOf[c.O.I2 forSome { val c: C }].typeSymbol, typeOf[D.type], typeOf[C].typeSymbol) res6: u.Type = D.O.Id
* | Merge pull request #2079 from JamesIry/2.10.x_SI-7070James Iry2013-02-075-5/+0
|\ \ | | | | | | SI-7070 Turn restriction on companions in pkg objs into warning
| * | SI-7070 Turn restriction on companions in pkg objs into warningJames Iry2013-02-065-5/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The implementation restriction created from SI-5954 in 3ef487ecb6733bfe3c13d89780ebcfc81f9a5ea0 has two problems. 1) The problematic code works fine if compile with sbt. That means the restriction is breaking some people needlessly. 2) It's not binary compatible. To fix all that this commit changes the error into a warning and removes the setting used to get around the restriction.
* | | Merge pull request #1995 from retronym/ticket/5082James Iry2013-02-071-0/+14
|\ \ \ | | | | | | | | SI-5082 Cycle avoidance between case companions
| * | | SI-5082 Cycle avoidance between case companionsJason Zaugg2013-02-071-0/+14
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We can synthesize the case companion unapply without forcing the info of the case class, by looking at the parameters in the `ClassDef` tree, rather than at `sym.caseFieldAccessors`. Access to non-public case class fields routed through the already-renamed case accessor methods. The renamings are conveyed via a back-channel (a per-run map, `renamedCaseAccessors`), rather than via the types to give us enough slack to avoid the cycle. Some special treatment of private[this] parameters is needed to avoid a misleading error message. Fortunately, we can determine this without forcing the info of the case class, by inspecting the parameter accessor trees. This change may allow us to resurrect the case class ProductN parentage, which was trialled but abandoned in the lead up to 2.10.0.
* | | SI-7100 Fixed infinite recursion in duplicatorsVlad Ureche2013-02-071-0/+6
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* | | Merge pull request #2059 from VladUreche/issue/7060James Iry2013-02-062-0/+12
|\ \ \ | |_|/ |/| | SI-7060 More conservative dead code elim marking
| * | SI-7060 More conservative dead code elim markingVlad Ureche2013-02-052-0/+12
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In dead code elimination, a DROP instruction that gets marked as useful and can be reached via several paths needs to also mark all the reaching definitions as useful, else we'll get unbalanced stacks on the two paths. A simplistic example: ``` BB1: CALL X // useful, leaves a LONG on the stack JUMP BB3 BB2: LOAD_FIELD Y // not useful JUMP BB3 BB3: DROP LONG // useful because "CALL X" is useful // but unless we mark "LOAD_FIELD Y" as useful too // we'll get unbalanced stacks when reaching BB3 ``` This patch addresses the unbalanced stack problem by adding all the reaching definitions of a useful DROP as useful instructions too.
* | Merge pull request #1992 from retronym/ticket/7033Adriaan Moors2013-02-041-0/+15
|\ \ | |/ |/| SI-7033 Be symful when creating factory methods.
| * SI-7033 Be symful when creating factory methods.Jason Zaugg2013-02-021-0/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Implicit class factory methods were synthesizing the reference to the class as `Ident(classDef.name)`, which was unhygienic in case of `implicit class X[X]`. To use symbols without causing a cycle, I switched from `REF(symbol)` to `Ident(symbol)`. The former calls into: at scala.reflect.internal.TreeGen.mkAttributedSelect(TreeGen.scala:184) at scala.reflect.internal.TreeGen.mkAttributedRef(TreeGen.scala:124) at scala.reflect.internal.TreeGen.mkAttributedRef(TreeGen.scala:130) at scala.tools.nsc.ast.TreeDSL$CODE$.REF(TreeDSL.scala:307) which forces the info of enclosing module and forms a cycle.
* | Merge pull request #2022 from lrytz/analyzerPlugins210Lukas Rytz2013-02-035-1/+22
|\ \ | | | | | | Analyzer Plugins
| * | Fix context for type checking early initializersLukas Rytz2013-02-031-0/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before: scala> class A { class C extends { val x: A = this } with AnyRef } <console>:7: error: type mismatch; found : A.this.C required: A class A { class C extends { val x: A = this } with AnyRef } ^ Note that the same thing is necessary and already done in Namers (see def createNamer). The whole logic of when and how to create contexts should be factored out and reused in Namer and Typer. ( My Hobby [1]: detecting compiler by just looking at its soruce [1] http://www.explainxkcd.com/wiki/index.php?title=Category:My_Hobby )
| * | SI-1803, plus documentation and cleanups in Namers, mainly in typeSigLukas Rytz2013-02-033-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - when typing (and naming) a ValDef, tpt and rhs are now type checked in the same context (the inner / ValDef context). this does not change any behavior, but is more uniform (same as for DefDef). martin told me (offline) that this change is desirable if it doesn't break anything. (it doesn't). - typeSig is now more uniform with a separate method for each case (methodSig, valDefSig, etc). methodSig was cleaned up (no more variables) and documented. the type returned by methodSig no longer contains / refers to type skolems, but to the actual type parameters (so we don't need to replace the skolems lateron). - documentation on constructor contexts, type skolems - more tests for SI-5543
| * | Keep annotations when computing lubsLukas Rytz2013-02-031-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | Integrates annotationsLub into lub. Also fixes SubstSymMap when mapping over annotaion trees. I don't understand what the previous code was supposed to achieve, but it crashed in some of my examples.
* | | SI-7022 Additional test case for value class w. boundsJason Zaugg2013-02-021-0/+9
| | | | | | | | | | | | | | | As reported against 2.10.0, and as fixed by SI-6482, which was backported in the previous commit.
* | | [backport] SI-6482, lost bounds in extension methods.Jason Zaugg2013-02-021-0/+11
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Squashed commit of the following: commit 5c156185306ba797c0443d9dccae0ae7ce462a1f Author: Paul Phillips <paulp@improving.org> Date: Sat Oct 6 15:42:50 2012 -0700 A little more housecleaning in ExtensionMethods. The only real contribution is readability. (cherry picked from commit 61f12faacaaccf366f9211ba6493fb042a91f1d2) Conflicts: src/compiler/scala/tools/nsc/transform/ExtensionMethods.scala commit 79f443edf584745d614e24fb9ca6644c6b18d439 Author: Paul Phillips <paulp@improving.org> Date: Sat Oct 6 14:22:19 2012 -0700 Incorporated pull request feedback. (cherry picked from commit 153ccb4757718cceb219988f30381f73362e6075) commit 707f580b0cdcb01e27ca4c76991dea427945b5bd Author: Paul Phillips <paulp@improving.org> Date: Sat Oct 6 10:20:45 2012 -0700 Fix for SI-6482, lost bounds in extension methods. That was a good one. How to create a new method with type parameters from multiple sources, herein. (cherry picked from commit ff9f60f420c090b6716c927ab0359b082f2299de) commit 8889c7a13f74bc175e48aa2209549089a974c2af Author: Paul Phillips <paulp@improving.org> Date: Fri Oct 5 22:19:52 2012 -0700 Responded to comment about how many isCoercibles there are. I make the case that there is only one. (cherry picked from commit 883f1ac88dd7cec5882d42d6b48d7f267d1f6e00)
* | Merge pull request #1975 from retronym/ticket/6601-revertJames Iry2013-02-012-0/+11
|\ \ | | | | | | Revert "SI-6601 Publicise derived value contstructor after pickler"
| * | A test case to guide the eventual fix for SI-6601.Jason Zaugg2013-01-272-0/+11
| |/ | | | | | | | | This demonstrates the need for the reversion in the previous commit.
* | Merge pull request #1998 from JamesIry/2.10.x_6963_2Adriaan Moors2013-02-012-0/+26
|\ \ | | | | | | SI-6963 Add version to -Xmigration
| * | SI-6963 Add version to -XmigrationJames Iry2013-01-292-0/+26
| |/ | | | | | | | | | | | | | | | | Adds an optional version parameter to the -Xmigration compiler setting. Doing -Xmigration without version number behaves as it used to by dumping every possible migration warning. This commit adds a ScalaVersion class (plus ancillary stuff), and a ScalaVersionSetting.
* | Merge pull request #2015 from paulp/rc1-backportsPaul Phillips2013-01-3110-0/+114
|\ \ | | | | | | 10 backports
| * | SI-6595, lost modifiers in early defs.Paul Phillips2013-01-302-0/+19
| | | | | | | | | | | | | | | | | | | | | | | | [backport] Saw this by accident; the trees created for early defs would wholesale replace the modifiers with PRESUPER rather than combining them. FINAL was lost that way, as would be any other modifiers which might be valid there.
| * | SI-6072, crasher with overloaded eq.Paul Phillips2013-01-301-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | [backport] You don't want to do name-based selections in later phases if you can help it, because there is nobody left to resolve your overloads. If as in this example you're calling a known method, use the symbol. Review by @hubertp.
| * | SI-5604, selections on package objects.Paul Phillips2013-01-305-0/+31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [backport] mkAttributedSelect, which creates a Select tree based on a symbol, has been a major source of package object bugs, because it has not been accurately identifying selections on package objects. When selecting foo.bar, if foo turns out to be a package object, the created Select tree must be foo.`package`.bar However mkAttributedSelect was only examining the owner of the symbol, which means it would work if the package object defined bar directly, but not if it inherited it.
| * | SI-5859, inapplicable varargs.Paul Phillips2013-01-301-0/+15
| | | | | | | | | | | | | | | [backport] And other polishing related to varargs handling.
| * | SI-5130, precision disappearing from refinement.Paul Phillips2013-01-301-0/+46
| | | | | | | | | | | | | | | [backport] Remove some code, win a prize.
* | | Merge pull request #1989 from adriaanm/rework-pr-1945Paul Phillips2013-01-312-32/+0
|\ \ \ | | | | | | | | SI-6968 Simple Tuple patterns aren't irrefutable
| * | | SI-6968 Simple Tuple patterns aren't irrefutableJason Zaugg2013-01-272-32/+0
| | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Reverts part of c82ecab. The parser can't assume that a pattern `(a, b)` will match, as results of `.isInstanceOf[Tuple2]` can't be statically known until after the typer. The reopens SI-1336, SI-5589 and SI-4574, in exchange for fixing this regression SI-6968. Keeping all of those fixed will require a better definition of irrefutability, and some acrobatics to ensure safe passage to the ambiguous trees through typechecking.
* | | Merge pull request #1997 from retronym/ticket/7035Paul Phillips2013-01-301-0/+15
|\ \ \ | | | | | | | | SI-7035 Centralize case field accessor sorting.
| * | | SI-7035 Centralize case field accessor sorting.Jason Zaugg2013-01-281-0/+15
| |/ / | | | | | | | | | | | | | | | It is both burdensome and dangerous to expect callers to reorder these. This was seen in the field permutation in the unapply method; a regression in 2.10.0.
* | / SI-6516, macros comparing types with == instead of =:=.Paul Phillips2013-01-301-0/+19
| |/ |/| | | | | | | | | | | | | | | I gift-wrapped this ticket four months ago: 'I think it will be enough to say "tpe =:= MacroContextClass.tpe" rather than == .' Indeed. Had to open my own gift. Thanks, paulp!
* | SI-6551 Expand test case into uncomfortable areas.Jason Zaugg2013-01-291-11/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | trait T { type U } class A(val a: T) extends AnyVal { def foo[TT <: a.U] = 0 } It works! But it's pure serendipity. After extmethods, the careful student of ASTs will find: object A { final def foo$extension[TT >: Nothing <: A.this.a.U]($this: A): Int = 0; } `A.this` doesn't belong. For now we just include this case under our test umbrella.
* | SI-6651 Substitute `this` in extension method sigsJason Zaugg2013-01-291-0/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This allows for the likes of: class A[X](val x: X) extends AnyVal { def foo(xy: x.Y) {} } We have to do this in both directions, when synthesizing the extension method in `Extender#transform`, and later on when Erasure tries to find the corresponding extension methods by backing out the original signatures from the signatures of the synthesized methods in the companion. In the first case, we have to be careful to use a stable reference to the `self` parameter, which can satisfy the dependent types.
* | Merge pull request #1981 from retronym/backport/1187Adriaan Moors2013-01-281-0/+29
|\ \ | | | | | | [backport] SI-3577 BoundedWildcardType handling
| * | [backport] SI-3577 BoundedWildcardType handlingJason Zaugg2013-01-261-0/+29
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 3c91b32d699a9e29d685ac20c9805f96c9f2db2c Author: Jason Zaugg <jzaugg@gmail.com> Date: Fri Aug 24 01:16:47 2012 +0200 Mention BoundedWildcardType in "a standard type pattern match". (cherry picked from commit 00e46b3dbcea2b72fd3941b7ffc2efba382871e9) commit 0664be2b69b1ce013e937bc93f4e84b891676f1f Author: Jason Zaugg <jzaugg@gmail.com> Date: Fri Aug 24 01:05:07 2012 +0200 Make RefChecks#validateVariance aware of BoundedWildcardType. The only test case that I know for this will be neutered by the imminent fix for SI-6258; so I haven't been able to test this. But trying this manually, you can see that this patch defers the the SI-6258 to the erasure phase. Original: scala.MatchError: ? (of class scala.reflect.internal.Types$BoundedWildcardType) at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer$$anon$3.scala$tools$nsc$typechecker$RefChecks$RefCheckTransformer$$anon$$validateVariance$1(RefChecks.scala:894) at scala.tools.nsc.typechecker.RefChecks$RefCheckTransformer$$anon$3.validateVariance(RefChecks.scala:965) Modified: java.lang.ClassCastException: scala.reflect.internal.Types$TypeRef$$anon$6 cannot be cast to scala.reflect.internal.Types$TypeBounds at scala.reflect.internal.Types$TypeMap.mapOver(Types.scala:4160) at scala.reflect.internal.transform.Erasure$ErasureMap.apply(Erasure.scala:156) (cherry picked from commit 2b4e7183fd24113cca5e868456668fd05c848168) commit 6ad651c94faf463133c742feb2aee59ef782ea1f Author: Jason Zaugg <jzaugg@gmail.com> Date: Fri Aug 24 00:54:59 2012 +0200 SI-3577 Make varianceInType aware of BoundedWildcardType. (cherry picked from commit 21105654c40ed0c462142bcbb6c8eced77f8b07a)
* | Merge pull request #1936 from retronym/ticket/6891Adriaan Moors2013-01-282-0/+27
|\ \ | |/ |/| SI-6891 Fix value class + tailrec crasher.
| * SI-6891 Fix value class + tailrec crasher.Jason Zaugg2013-01-262-0/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | rhs.substituteSymbols(old, new) leaves us with: def loop#12225(x#12226: A#15491): scala#21.this.Unit#1615 = loop#12225(x#12226) In which the TermSymbol x#12226 has a stale info, pointing at the A#7274, the class type parameter, rather than A#15491, the corresponding type parameter of the synthetic backing method. I've improved `TreeSymSubstituter` to substitute not only `Tree#{tpe, symbol}`, but also `DefTree#sym.info`. The `pos` test that triggered the new code path are listed here: https://gist.github.com/4575687 AFAICS, no special treatment of Function, Return, or Import is needed in TreeSymSubstutor.
* | Merge pull request #1956 from JamesIry/SI-7011_2.10.xJames Iry2013-01-252-0/+8
|\ \ | | | | | | SI-7011 Fix finding constructor type in captured var definitions
| * | SI-7011 Fix finding constructor type in captured var definitionsJames Iry2013-01-232-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a captured var was initialized with an empty tree then finding the type of the empty tree was being handled improperly. The fix is to look for primary constructors on the tree's type symbol rather than the tree's symbol. A test is included. In order to make the problem more testable the debug logging of the issue is changed to a debug warn.
* | | Merge pull request #1910 from retronym/ticket/6976Paul Phillips2013-01-253-0/+44
|\ \ \ | | | | | | | | SI-6976 Fix value class separate compilation crasher.
| * | | SI-6976 Fix value class separate compilation crasher.Jason Zaugg2013-01-163-0/+44
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We can't guarantee that the owner of the value class is initialized, and if it isn't, the search for the companion module will turn up bubkis. This is a localized fix, but I'd be suprised if there weren't other places that suffered from the same problem. Wouldn't it be nicer to have something like: // doesn't force info sym.raw.info sym.raw.companionModule // forces info sym.info sym.companionModule
* | | | Merge pull request #1935 from retronym/ticket/6994Paul Phillips2013-01-242-0/+9
|\ \ \ \ | |_|/ / |/| | | SI-6994 Avoid spurious promiscuous catch warning
| * | | SI-6994 Avoid spurious promiscuous catch warningJason Zaugg2013-01-202-0/+9
| | |/ | |/| | | | | | | | | | It was being issued upon re-typechecking of a transformed tree. Now we disable the warning post-typer.
* / | SI-6942 more efficient unreachability analysisAdriaan Moors2013-01-173-0/+300
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Avoid blowing the stack/the analysis budget by more eagerly translating the propositions that model matches to CNF. First building a large proposition that represents the match, and then converting to CNF tends to blow the stack. Luckily, it's easy to convert to CNF as we go. The optimization relies on `CNF(P1 /\ ... /\ PN) == CNF(P1) ++ CNF(...) ++ CNF(PN)`: Normalizing a conjunction of propositions yields the same formula as concatenating the normalized conjuncts. CNF conversion is expensive for large propositions, so we push it down into the conjunction and then concatenate the resulting arrays of clauses (which is cheap). (CNF converts a free-form proposition into an `Array[Set[Lit]]`, where: - the Array's elements are /\'ed together; - and the Set's elements are \/'ed; - a Lit is a possibly negated variable.) NOTE: - removeVarEq may throw an AnalysisBudget.Exception - also reworked the interface used to build formula, so that we can more easily plug in SAT4J when the time comes
* | Merge pull request #1892 from retronym/ticket/6479Paul Phillips2013-01-151-0/+56
|\ \ | | | | | | SI-6479 Don't lift try exprs in label arguments.
| * | SI-6479 Don't lift try exprs in label arguments.Jason Zaugg2013-01-131-0/+56
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The new pattern matcher uses label jumps to GOTO the next case. Uncurry treated these like regular method arguments, and performed the liftedTree() transformation, which ensures that try expressions are only used in a statement position. Even try in statement position of a block used as such an argument are subject to the same transform. This transform stems from the JVM limitation, that try/catch does not leave a value on the stack. See b194446. This commit changes Uncurry to avoid this transform for arguments to label jumps. This avoids needlessly indirect code, and enables tail call elimination in more cases. As an example, Scala 2.10.0 transforms the last method of the enclosed test case to: try { case <synthetic> val x1: Int = 1; case5(){ if (2.==(x1)) { val x2: Int = x1; matchEnd4({ { def liftedTree2(): Unit = try { throw new scala.runtime.NonLocalReturnControl[Unit](nonLocalReturnKey1, ()) } catch { case (e @ (_: ClassNotFoundException)) => () }; liftedTree2() }; TailrecAfterTryCatch.this.bad() }) } else case6() }; case6(){ matchEnd4(throw new MatchError(x1)) }; matchEnd4(x: Unit){ x } } catch { case (ex @ (_: scala.runtime.NonLocalReturnControl[Unit @unchecked])) => if (ex.key().eq(nonLocalReturnKey1)) ex.value() else throw ex } After this patch: @scala.annotation.tailrec final def bad(): Unit = { case <synthetic> val x1: Int = 1; case5(){ if (2.==(x1)) { <synthetic> val x2: Int = x1; matchEnd4({ try { return () } catch { case (e @ (_: ClassNotFoundException)) => () }; TailrecAfterTryCatch.this.bad() }) } else case6() }; case6(){ matchEnd4(throw new MatchError(x1)) }; matchEnd4(x: Unit){ x } }
* | | Merge pull request #1878 from adriaanm/ticket-6925Adriaan Moors2013-01-142-0/+27
|\ \ \ | | | | | | | | SI-6925 use concrete type in applyOrElse's match's selecto
| * | | rework partial function synthesisAdriaan Moors2013-01-091-0/+18
| | | | | | | | | | | | | | | | | | | | no behavioral changes, just highly overdue cleanup some TODOs for further improvements
| * | | SI-6925 use concrete type in applyOrElse's match's selectorAdriaan Moors2013-01-091-0/+9
| | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix a regression introduced in 28483739c3: PartialFunction synthesis was broken so that we'd get: ``` scala> def f[T](xs: Set[T]) = xs collect { case x => x } f: [T](xs: Set[T])scala.collection.immutable.Set[_ <: T] ``` rather than ``` scala> def f[T](xs: Set[T]) = xs collect { case x => x } f: [T](xs: Set[T])scala.collection.immutable.Set[T] ```