From dcb25c73739f1b5d40e92cd07acae5f7940f82a6 Mon Sep 17 00:00:00 2001 From: Martin Odersky Date: Tue, 5 May 2015 22:18:46 +0200 Subject: Drop the requirement that extractors with `get` must implement Product We used to require that the result type of an extractor `get` is a product, or else the type of the `get` itself would be taken as the result type of the unapply. This is now relaxed so that we automatically select with _1, _2, ... as soon as there are multiple argument patterns, and (1) the result type is not a Seq, (2) the number of consecutive product conselectors matches the number of arguments. --- src/dotty/tools/dotc/typer/Applications.scala | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) (limited to 'src/dotty/tools/dotc/typer/Applications.scala') diff --git a/src/dotty/tools/dotc/typer/Applications.scala b/src/dotty/tools/dotc/typer/Applications.scala index 7a826fee8..ce181c0cc 100644 --- a/src/dotty/tools/dotc/typer/Applications.scala +++ b/src/dotty/tools/dotc/typer/Applications.scala @@ -51,9 +51,12 @@ object Applications { sels.takeWhile(_.exists).toList } - def getUnapplySelectors(tp: Type, args:List[untpd.Tree], pos: Position = NoPosition)(implicit ctx: Context): List[Type] = - if (defn.isProductSubType(tp) && args.length > 1) productSelectorTypes(tp, pos) - else tp :: Nil + def getUnapplySelectors(tp: Type, args: List[untpd.Tree], pos: Position = NoPosition)(implicit ctx: Context): List[Type] = + if (args.length > 1 && !(tp.derivesFrom(defn.SeqClass))) { + val sels = productSelectorTypes(tp, pos) + if (sels.length == args.length) sels + else tp :: Nil + } else tp :: Nil def unapplyArgs(unapplyResult: Type, unapplyFn:Tree, args:List[untpd.Tree], pos: Position = NoPosition)(implicit ctx: Context): List[Type] = { @@ -747,6 +750,7 @@ trait Applications extends Compatibility { self: Typer => case _ => args } if (argTypes.length != bunchedArgs.length) { + println(argTypes) ctx.error(d"wrong number of argument patterns for $qual; expected: ($argTypes%, %)", tree.pos) argTypes = argTypes.take(args.length) ++ List.fill(argTypes.length - args.length)(WildcardType) -- cgit v1.2.3