From a1c00ae4b2df051c33384269b6b983746e537aee Mon Sep 17 00:00:00 2001 From: Paul Phillips Date: Tue, 17 Dec 2013 14:20:49 -0800 Subject: Dotless type application for infix operators. When you have an aesthetic expresion like def f(xs: Iterator[Int]) = ( xs takeWhile (_ < 1000) map (_ * -1) filter (_ % 2 == 0) flatMap (x => List(x, x)) reduceOption (_ + _) maxBy (_.toString) ) And then for whatever reason you have to perform explicit type application in the midst of that expression, it's aggravating in the extreme that it has (had) to be rewritten in its entirety to accommodate that change. So now you can perform type application in the middle of it. For reasons not entirely clear to me postfix operators are excluded. The discussion as well as the approval for the infix variation of it can be found at: https://groups.google.com/forum/#!msg/scala-language/eJl1wnkEz9M/hR984-lqC5EJ --- .../scala/tools/nsc/ast/parser/Parsers.scala | 22 ++++++++++++++-------- 1 file changed, 14 insertions(+), 8 deletions(-) (limited to 'src/compiler/scala/tools/nsc/ast/parser/Parsers.scala') diff --git a/src/compiler/scala/tools/nsc/ast/parser/Parsers.scala b/src/compiler/scala/tools/nsc/ast/parser/Parsers.scala index 91db1bb92a..2134058287 100644 --- a/src/compiler/scala/tools/nsc/ast/parser/Parsers.scala +++ b/src/compiler/scala/tools/nsc/ast/parser/Parsers.scala @@ -133,7 +133,7 @@ self => val global: Global import global._ - case class OpInfo(lhs: Tree, operator: TermName, offset: Offset) { + case class OpInfo(lhs: Tree, operator: TermName, targs: List[Tree], offset: Offset) { def precedence = Precedence(operator.toString) } @@ -795,10 +795,13 @@ self => private def opHead = opstack.head private def headPrecedence = opHead.precedence private def popOpInfo(): OpInfo = try opHead finally opstack = opstack.tail - private def pushOpInfo(top: Tree) { - val opinfo = OpInfo(top, in.name, in.offset) - opstack ::= opinfo + private def pushOpInfo(top: Tree): Unit = { + val name = in.name + val offset = in.offset ident() + val targs = if (in.token == LBRACKET) exprTypeArgs() else Nil + val opinfo = OpInfo(top, name, targs, offset) + opstack ::= opinfo } def checkHeadAssoc(leftAssoc: Boolean) = checkAssoc(opHead.offset, opHead.operator, leftAssoc) @@ -808,6 +811,9 @@ self => ) def finishPostfixOp(start: Int, base: List[OpInfo], opinfo: OpInfo): Tree = { + if (opinfo.targs.nonEmpty) + syntaxError(opinfo.offset, "type application is not allowed for postfix operators") + val od = stripParens(reduceExprStack(base, opinfo.lhs)) makePostfixSelect(start, opinfo.offset, od, opinfo.operator) } @@ -817,7 +823,7 @@ self => val operatorPos: Position = Position.range(rhs.pos.source, offset, offset, offset + operator.length) val pos = lhs.pos union rhs.pos union operatorPos withPoint offset - atPos(pos)(makeBinop(isExpr, lhs, operator, rhs, operatorPos)) + atPos(pos)(makeBinop(isExpr, lhs, operator, rhs, operatorPos, opinfo.targs)) } def reduceExprStack(base: List[OpInfo], top: Tree): Tree = reduceStack(isExpr = true, base, top) @@ -1893,9 +1899,9 @@ self => def isDelimiter = in.token == RPAREN || in.token == RBRACE def isCommaOrDelimiter = isComma || isDelimiter val (isUnderscore, isStar) = opstack match { - case OpInfo(Ident(nme.WILDCARD), nme.STAR, _) :: _ => (true, true) - case OpInfo(_, nme.STAR, _) :: _ => (false, true) - case _ => (false, false) + case OpInfo(Ident(nme.WILDCARD), nme.STAR, _, _) :: _ => (true, true) + case OpInfo(_, nme.STAR, _, _) :: _ => (false, true) + case _ => (false, false) } def isSeqPatternClose = isUnderscore && isStar && isSequenceOK && isDelimiter val preamble = "bad simple pattern:" -- cgit v1.2.3