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author | Martin Odersky <odersky@gmail.com> | 2014-12-03 18:27:28 +0100 |
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committer | Martin Odersky <odersky@gmail.com> | 2014-12-03 18:27:35 +0100 |
commit | a612da844fc7c9e9cc920e4b9c0ecb65e0273d0c (patch) | |
tree | 6750a1d6664b743226a450a44a58dc167640d6c2 /src | |
parent | 8fb5e1e8ee69f14fec52056d43528755544870b7 (diff) | |
download | dotty-a612da844fc7c9e9cc920e4b9c0ecb65e0273d0c.tar.gz dotty-a612da844fc7c9e9cc920e4b9c0ecb65e0273d0c.tar.bz2 dotty-a612da844fc7c9e9cc920e4b9c0ecb65e0273d0c.zip |
Add new SeqLiterals phase.
Replaces SeqLiterals by JavaSeqLiterals, because the latter's
(array-)type is preserved after erasure.
Diffstat (limited to 'src')
-rw-r--r-- | src/dotty/tools/dotc/Compiler.scala | 1 | ||||
-rw-r--r-- | src/dotty/tools/dotc/transform/SeqLiterals.scala | 49 |
2 files changed, 50 insertions, 0 deletions
diff --git a/src/dotty/tools/dotc/Compiler.scala b/src/dotty/tools/dotc/Compiler.scala index 004a3868c..c414de130 100644 --- a/src/dotty/tools/dotc/Compiler.scala +++ b/src/dotty/tools/dotc/Compiler.scala @@ -48,6 +48,7 @@ class Compiler { new ExplicitOuter, new Splitter), List(new ElimByName, + new SeqLiterals, new InterceptedMethods, new Literalize, new Getters, diff --git a/src/dotty/tools/dotc/transform/SeqLiterals.scala b/src/dotty/tools/dotc/transform/SeqLiterals.scala new file mode 100644 index 000000000..021516454 --- /dev/null +++ b/src/dotty/tools/dotc/transform/SeqLiterals.scala @@ -0,0 +1,49 @@ +package dotty.tools.dotc +package transform + +import core._ +import Types._ +import dotty.tools.dotc.transform.TreeTransforms._ +import Contexts.Context +import Symbols._ +import Phases._ +import Decorators._ + +/** A transformer that eliminates SeqLiteral's, transforming `SeqLiteral(elems)` to an operation + * equivalent to + * + * JavaSeqLiteral(elems).toSeq + * + * Instead of `toSeq`, which takes an implicit, the appropriate "wrapArray" method + * is called directly. The reason for this step is that JavaSeqLiterals, being arrays + * keep a precise type after erasure, whereas SeqLiterals only get the erased type `Seq`, + */ +class SeqLiterals extends MiniPhaseTransform { thisTransformer => + import ast.tpd._ + + override def phaseName = "seqLiterals" + override def treeTransformPhase = thisTransformer.next + override def runsAfter: Set[Class[_ <: Phase]] = Set(classOf[PatternMatcher]) + + override def checkPostCondition(tree: Tree)(implicit ctx: Context): Unit = tree match { + case tpd: SeqLiteral => assert(tpd.isInstanceOf[JavaSeqLiteral]) + case _ => + } + + override def transformSeqLiteral(tree: SeqLiteral)(implicit ctx: Context, info: TransformerInfo): Tree = tree match { + case tree: JavaSeqLiteral => tree + case _ => + val arr = JavaSeqLiteral(tree.elems) + //println(i"trans seq $tree, arr = $arr: ${arr.tpe} ${arr.tpe.elemType}") + val elemtp = arr.tpe.elemType.bounds.hi + val elemCls = elemtp.classSymbol + val (wrapMethStr, targs) = + if (elemCls.isPrimitiveValueClass) (s"wrap${elemCls.name}Array", Nil) + else if (elemtp derivesFrom defn.ObjectClass) ("wrapRefArray", elemtp :: Nil) + else ("genericWrapArray", elemtp :: Nil) + ref(defn.ScalaPredefModule) + .select(wrapMethStr.toTermName) + .appliedToTypes(targs) + .appliedTo(arr) + } +} |