/* NSC -- new Scala compiler
* Copyright 2005-2009 LAMP/EPFL
* @author Martin Odersky
*/
// $Id$
//todo: allow infix type patterns
package scala.tools.nsc.ast.parser
import scala.collection.mutable.ListBuffer
import scala.tools.nsc.util.{Position, OffsetPosition, NoPosition, BatchSourceFile}
import symtab.Flags
import Tokens._
//todo verify when stableId's should be just plain qualified type ids
/**
Performs the following context-free rewritings:
*
* -
* Places all pattern variables in Bind nodes. In a pattern, for
* identifiers
x
:
* x => x @ _
* x:T => x @ (_ : T)
*
* - Removes pattern definitions (PatDef's) as follows:
* If pattern is a simple (typed) identifier:
* val x = e ==> val x = e
* val x: T = e ==> val x: T = e
*
* if there are no variables in pattern
* val p = e ==> e match (case p => ())
*
* if there is exactly one variable in pattern
* val x_1 = e match (case p => (x_1))
*
* if there is more than one variable in pattern
* val p = e ==> private synthetic val t$ = e match (case p => (x_1, ..., x_N))
* val x_1 = t$._1
* ...
* val x_N = t$._N
*
* -
* Removes function types as follows:
* (argtpes) => restpe ==> scala.Function_n[argtpes, restpe]
*
* -
* Wraps naked case definitions in a match as follows:
* { cases } ==> (x => x.match {cases}), except when already argument to match
*
*
*/
trait Parsers extends NewScanners with MarkupParsers {
val global : Global
import global._
private val glob: global.type = global
import global.posAssigner.atPos
case class OpInfo(operand: Tree, operator: Name, pos: Int)
/** ...
*
* @author Sean McDirmid
*/
class UnitParser(val unit: global.CompilationUnit) extends Parser {
val in = new UnitScanner(unit)
def freshName(pos: Position, prefix: String): Name =
unit.fresh.newName(pos, prefix)
implicit def i2p(offset: Int): Position = new OffsetPosition(unit.source,offset)
def warning(pos: Int, msg: String) { unit.warning(pos, msg) }
def incompleteInputError(msg: String) {
unit.incompleteInputError(unit.source.asInstanceOf[BatchSourceFile].content.length - 1, msg)
}
def deprecationWarning(pos: Int, msg: String) {
unit.deprecationWarning(pos, msg)
}
def syntaxError(pos: Int, msg: String) { unit.error(pos, msg) }
/** the markup parser */
def xmlp = {
if (xmlp0 == null)
xmlp0 = new MarkupParser(this, true)
xmlp0
}
object symbXMLBuilder extends SymbolicXMLBuilder(treeBuilder, this, true) { // DEBUG choices
val global: Parsers.this.global.type = Parsers.this.global
def freshName(prefix: String): Name = UnitParser.this.freshName(NoPosition, prefix)
}
private var xmlp0: MarkupParser = null
def xmlLiteral : Tree = xmlp.xLiteral
def xmlLiteralPattern : Tree = xmlp.xLiteralPattern
}
// parser constants, here so they don't pollute parser debug listing
private object ParserConfiguration {
final val Local = 0
final val InBlock = 1
final val InTemplate = 2
final val MINUS: Name = "-"
final val PLUS : Name = "+"
final val BANG : Name = "!"
final val TILDE: Name = "~"
final val AMP : Name = "&"
final val SLASH: Name = "/"
final val STAR : Name = "*"
final val BAR : Name = "|"
final val LT : Name = "<"
}
abstract class Parser {
ParserConfiguration.hashCode
import ParserConfiguration._
val in: ParserScanner
//val unit : CompilationUnit
//import in.ScanPosition
protected def freshName(pos: Position, prefix: String): Name
protected def posToReport: Int = in.currentPos
protected implicit def i2p(offset: Int): Position
//private implicit def p2i(pos: Position) = pos.offset.get
private def inToken = in.token
private def inSkipToken = in.skipToken
private def inNextToken = in.nextToken
private def inCurrentPos = in.currentPos
private def inNextTokenCode : Int = in.nextTokenCode
private def inName = in.name
private def charVal = in.charVal
private def intVal(isNegated: Boolean) = in.intVal(isNegated).asInstanceOf[Int]
private def longVal(isNegated: Boolean) = in.intVal(isNegated)
private def floatVal(isNegated: Boolean) = in.floatVal(isNegated).asInstanceOf[Float]
private def doubleVal(isNegated: Boolean) = in.floatVal(isNegated)
private def stringVal = in.stringVal
/** whether a non-continuable syntax error has been seen */
//private var syntaxErrorSeen = false
private var lastErrorPos : Int = -1
object treeBuilder extends TreeBuilder {
val global: Parsers.this.global.type = Parsers.this.global
def freshName(pos : Position, prefix: String): Name =
Parser.this.freshName(pos, prefix)
}
import treeBuilder._
/** The implicit view parameters of the surrounding class */
var implicitClassViews: List[Tree] = Nil
/** this is the general parse method
*/
def parse(): Tree = {
val t = compilationUnit()
accept(EOF)
t
}
/* --------------- PLACEHOLDERS ------------------------------------------- */
/** The implicit parameters introduced by `_' in the current expression.
* Parameters appear in reverse order
*/
var placeholderParams: List[ValDef] = Nil
/** The placeholderTypes introduced by `_' in the current type.
* Parameters appear in reverse order
*/
var placeholderTypes: List[TypeDef] = Nil
def checkNoEscapingPlaceholders[T](op: => T): T = {
val savedPlaceholderParams = placeholderParams
val savedPlaceholderTypes = placeholderTypes
placeholderParams = List()
placeholderTypes = List()
val res = op
placeholderParams match {
case vd :: _ =>
syntaxError(vd.pos, "unbound placeholder parameter", false)
placeholderParams = List()
case _ =>
}
placeholderTypes match {
case td :: _ =>
syntaxError(td.pos, "unbound wildcard type", false)
placeholderTypes = List()
case _ =>
}
placeholderParams = savedPlaceholderParams
placeholderTypes = savedPlaceholderTypes
res
}
def placeholderTypeBoundary(op: => Tree): Tree = {
val savedPlaceholderTypes = placeholderTypes
placeholderTypes = List()
var t = op
if (!placeholderTypes.isEmpty && t.isInstanceOf[AppliedTypeTree]) {
t = ExistentialTypeTree(t, placeholderTypes.reverse)
placeholderTypes = List()
}
placeholderTypes = placeholderTypes ::: savedPlaceholderTypes
t
}
/* ------------- ERROR HANDLING ------------------------------------------- */
protected def skip() {
var nparens = 0
var nbraces = 0
while (true) {
inToken match {
case EOF =>
return
case SEMI =>
if (nparens == 0 && nbraces == 0) return
case NEWLINE =>
if (nparens == 0 && nbraces == 0) return
case NEWLINES =>
if (nparens == 0 && nbraces == 0) return
case RPAREN =>
nparens -= 1
case RBRACE =>
if (nbraces == 0) return
nbraces -= 1
case LPAREN =>
nparens += 1
case LBRACE =>
nbraces += 1
case _ =>
}
inNextToken
}
}
def warning(pos: Int, msg: String): Unit
def incompleteInputError(msg: String): Unit
def deprecationWarning(pos: Int, msg: String): Unit
private def syntaxError(pos: Position, msg: String, skipIt: Boolean) {
pos.offset match {
case None => syntaxError(msg,skipIt)
case Some(offset) => syntaxError(offset, msg, skipIt)
}
}
def syntaxError(pos: Int, msg: String): Unit
def syntaxError(msg: String, skipIt: Boolean) {
syntaxError(inCurrentPos, msg, skipIt)
}
def syntaxError(pos: Int, msg: String, skipIt: Boolean) {
if (pos > lastErrorPos) {
syntaxError(pos, msg)
// no more errors on this token.
lastErrorPos = inCurrentPos
}
if (skipIt)
skip()
}
def warning(msg: String) { warning(inCurrentPos, msg) }
def syntaxErrorOrIncomplete(msg: String, skipIt: Boolean) {
val inToken = this.inToken
if (inToken == EOF)
incompleteInputError(msg)
else
syntaxError(inCurrentPos, msg, skipIt)
}
// unused.
/* Commented out because the comment says it is unused.
Probably eliminate eventually. GAW 2008.05.01
def mismatch(expected: Int, found: Int) {
val posToReport = this.posToReport
val msg =
ScannerConfiguration.token2string(expected) + " expected but " +
ScannerConfiguration.token2string(found) + " found."
if (found == EOF)
incompleteInputError(msg)
else
syntaxError(posToReport, msg, true)
}
*/
/** Consume one token of the specified type, or
* signal an error if it is not there.
*/
def accept(token: Int): Int = {
val pos = inCurrentPos
if (inToken != token) {
val posToReport =
//if (inCurrentPos.line(unit.source).get(0) > in.lastPos.line(unit.source).get(0))
// in.lastPos
//else
inCurrentPos
val msg =
ScannerConfiguration.token2string(token) + " expected but " +
ScannerConfiguration.token2string(inToken) + " found."
if (inToken == EOF)
incompleteInputError(msg)
else
syntaxError(posToReport, msg, true)
}
if (inToken == token) inNextToken
pos
}
def surround[T](open: Int, close: Int)(f: => T, orElse: T): T = {
val wasOpened = inToken == open
accept(open)
if (wasOpened) {
val ret = f
accept(close)
ret
} else orElse
}
/** semi = nl {nl} | `;'
* nl = `\n' // where allowed
*/
def acceptStatSep(): Boolean =
if (inToken == NEWLINE || inToken == NEWLINES) { inNextToken; true }
else {
val ret = inToken == SEMI
accept(SEMI)
ret
}
def errorTypeTree = TypeTree().setType(ErrorType).setPos((inCurrentPos))
def errorTermTree = Literal(Constant(null)).setPos((inCurrentPos))
def errorPatternTree = Ident(nme.WILDCARD).setPos((inCurrentPos))
/* -------------- TOKEN CLASSES ------------------------------------------- */
def isModifier: Boolean = inToken match {
case ABSTRACT | FINAL | SEALED | PRIVATE |
PROTECTED | OVERRIDE | IMPLICIT | LAZY => true
case _ => false
}
def isLocalModifier: Boolean = inToken match {
case ABSTRACT | FINAL | SEALED | IMPLICIT | LAZY => true
case _ => false
}
def isDefIntro: Boolean = inToken match {
case VAL | VAR | DEF | TYPE | OBJECT |
CASEOBJECT | CLASS | CASECLASS | TRAIT => true
case _ => false
}
def isDclIntro: Boolean = inToken match {
case VAL | VAR | DEF | TYPE => true
case _ => false
}
def isIdent = inToken == IDENTIFIER || inToken == BACKQUOTED_IDENT
def isExprIntroToken(token: Int): Boolean = token match {
case CHARLIT | INTLIT | LONGLIT | FLOATLIT | DOUBLELIT |
STRINGLIT | SYMBOLLIT | TRUE | FALSE | NULL | IDENTIFIER | BACKQUOTED_IDENT |
THIS | SUPER | IF | FOR | NEW | USCORE | TRY | WHILE |
DO | RETURN | THROW | LPAREN | LBRACE | XMLSTART => true
case _ => false
}
def isExprIntro: Boolean = isExprIntroToken(inToken)
def isTypeIntroToken(token: Int): Boolean = token match {
case IDENTIFIER | BACKQUOTED_IDENT | THIS |
SUPER | USCORE | LPAREN | AT => true
case _ => false
}
def isTypeIntro: Boolean = isTypeIntroToken(inToken)
def isStatSep(token: Int): Boolean =
token == NEWLINE || token == NEWLINES || token == SEMI
def isStatSep: Boolean = isStatSep(inToken)
/* --------- COMMENT AND ATTRIBUTE COLLECTION ----------------------------- */
/** Join the comment associated with a definition
*/
def joinComment(trees: => List[Tree]): List[Tree] = {
val buf = in.flushDoc
if ((buf ne null) && buf.length > 0) trees map (t => DocDef(buf, t) setPos t.pos)
else trees
}
/* ---------- TREE CONSTRUCTION ------------------------------------------- */
/** Convert tree to formal parameter list
*/
def convertToParams(tree: Tree): List[ValDef] = tree match {
case Parens(ts) =>
ts map convertToParam
case _ =>
List(convertToParam(tree))
}
/** Convert tree to formal parameter
*/
def convertToParam(tree: Tree): ValDef =
atPos(tree.pos) {
def removeAsPlaceholder(name: Name) {
placeholderParams = placeholderParams filter (_.name != name)
}
tree match {
case Ident(name) =>
removeAsPlaceholder(name)
ValDef(Modifiers(Flags.PARAM), name, TypeTree(), EmptyTree)
case Typed(tree @ Ident(name), tpe) if (tpe.isType) => // get the ident!
removeAsPlaceholder(name)
ValDef(Modifiers(Flags.PARAM), name, tpe, EmptyTree).setPos(tree.pos)
case _ =>
syntaxError(tree.pos, "not a legal formal parameter", false)
ValDef(Modifiers(Flags.PARAM), nme.ERROR, errorTypeTree, EmptyTree)
}
}
/** Convert (qual)ident to type identifier
*/
def convertToTypeId(tree: Tree): Tree = tree match {
case Ident(name) =>
Ident(name.toTypeName).setPos(tree.pos)
case Select(qual, name) =>
Select(qual, name.toTypeName).setPos(tree.pos)
case _ =>
syntaxError(tree.pos, "identifier expected", false)
errorTypeTree
}
/** make closure from tree staring with a `.' */
def makeDotClosure(tree: Tree): Tree = {
val pname = freshName(tree.pos, "x$")
def insertParam(tree: Tree): Tree = atPos(tree.pos) {
tree match {
case Ident(name) =>
Select(Ident(pname), name)
case Select(qual, name) =>
Select(insertParam(qual), name)
case Apply(fn, args) =>
Apply(insertParam(fn), args)
case TypeApply(fn, args) =>
TypeApply(insertParam(fn), args)
case _ =>
syntaxError(tree.pos, "cannot convert to closure", false)
errorTermTree
}
}
Function(List(makeSyntheticParam(pname)), insertParam(tree))
}
/* --------- OPERAND/OPERATOR STACK --------------------------------------- */
var opstack: List[OpInfo] = Nil
def precedence(operator: Name): Int =
if (operator eq nme.ERROR) -1
else {
val firstCh = operator(0)
if (((firstCh >= 'A') && (firstCh <= 'Z')) ||
((firstCh >= 'a') && (firstCh <= 'z')))
1
else if (nme.isOpAssignmentName(operator))
0
else
firstCh match {
case '|' => 2
case '^' => 3
case '&' => 4
case '=' | '!' => 5
case '<' | '>' => 6
case ':' => 7
case '+' | '-' => 8
case '*' | '/' | '%' => 9
case _ => 10
}
}
def checkSize(kind: String, size: Int, max: Int) {
if (size > max) syntaxError("too many "+kind+", maximum = "+max, false)
}
def checkAssoc(pos: Int, op: Name, leftAssoc: Boolean) =
if (treeInfo.isLeftAssoc(op) != leftAssoc)
syntaxError(
pos, "left- and right-associative operators with same precedence may not be mixed", false)
def reduceStack(isExpr: Boolean, base: List[OpInfo], top0: Tree,
prec: Int, leftAssoc: Boolean): Tree = {
var top = top0
if (opstack != base && precedence(opstack.head.operator) == prec)
checkAssoc(opstack.head.pos, opstack.head.operator, leftAssoc)
while (opstack != base &&
(prec < precedence(opstack.head.operator) ||
(leftAssoc && prec == precedence(opstack.head.operator)))) {
top = atPos(opstack.head.pos) {
makeBinop(isExpr, opstack.head.operand, opstack.head.operator, top)
}
opstack = opstack.tail
}
top
}
/* -------- IDENTIFIERS AND LITERALS ------------------------------------------- */
def ident(): Name =
if (inToken == IDENTIFIER || inToken == BACKQUOTED_IDENT) {
val name = inName.encode
inNextToken
name
} else {
accept(IDENTIFIER)
nme.ERROR
}
def selector(t: Tree): Tree =
atPos(inCurrentPos)(Select(t, ident()))
/** Path ::= StableId
* | [Ident `.'] this
* AnnotType ::= Path [`.' type]
*/
def path(thisOK: Boolean, typeOK: Boolean): Tree = {
var t: Tree = null
if (inToken == THIS) {
t = atPos(inSkipToken) { This(nme.EMPTY.toTypeName) }
if (!thisOK || inToken == DOT) {
t = selectors(t, typeOK, accept(DOT))
}
} else if (inToken == SUPER) {
// val pos = inCurrentPos
val pos = inSkipToken
val (mix,usePos) = mixinQualifierOpt(pos)
t = atPos(usePos) {
Super(nme.EMPTY.toTypeName, mix)
}
t = atPos(accept(DOT)) { selector(t) }
if (inToken == DOT)
t = selectors(t, typeOK, inSkipToken)
} else {
val i = atPos(inCurrentPos) {
if (inToken == BACKQUOTED_IDENT) new BackQuotedIdent(ident())
else Ident(ident())
}
t = i
if (inToken == DOT) {
val pos = inSkipToken
if (inToken == THIS) {
inNextToken
t = atPos(i.pos) { This(i.name.toTypeName) }
if (!thisOK || inToken == DOT)
t = selectors(t, typeOK, accept(DOT))
} else if (inToken == SUPER) {
inNextToken
val (mix,pos) = mixinQualifierOpt(i.pos)
t = atPos(pos) { Super(i.name.toTypeName, mix) }
t = atPos(accept(DOT)) {selector(t)}
if (inToken == DOT)
t = selectors(t, typeOK, inSkipToken)
} else {
t = selectors(t, typeOK, pos)
}
}
}
t
}
def selectors(t: Tree, typeOK: Boolean, pos : Int): Tree =
if (typeOK && inToken == TYPE) {
inNextToken
atPos(pos) { SingletonTypeTree(t) }
} else {
val t1 = atPos(pos) { selector(t); }
if (inToken == DOT) { selectors(t1, typeOK, inSkipToken) }
else t1
}
/** MixinQualifier ::= `[' Id `]'
*/
def mixinQualifierOpt(pos: Position): (Name, Position) =
if (inToken == LBRACKET) {
inNextToken
val pos = inCurrentPos
val name = ident().toTypeName
accept(RBRACKET)
(name, pos)
} else {
(nme.EMPTY.toTypeName, pos)
}
/** StableId ::= Id
* | Path `.' Id
* | [id '.'] super [`[' id `]']`.' id
*/
def stableId(): Tree =
path(false, false)
/** QualId ::= Id {`.' Id}
*/
def qualId(): Tree = {
val id = atPos(inCurrentPos) { Ident(ident()) }
if (inToken == DOT) { selectors(id, false, inSkipToken) }
else id
}
/** SimpleExpr ::= literal
* | symbol
* | null
*/
def literal(isPattern: Boolean, isNegated: Boolean): Tree = {
def litToTree() = atPos(inCurrentPos) {
Literal(
inToken match {
case CHARLIT => Constant(charVal)
case INTLIT => Constant(intVal(isNegated))
case LONGLIT => Constant(longVal(isNegated))
case FLOATLIT => Constant(floatVal(isNegated))
case DOUBLELIT => Constant(doubleVal(isNegated))
case STRINGLIT | SYMBOLLIT => Constant(stringVal)
case TRUE => Constant(true)
case FALSE => Constant(false)
case NULL => Constant(null)
case _ =>
syntaxErrorOrIncomplete("illegal literal", true)
null
})
}
val isSymLit = inToken == SYMBOLLIT
val t = litToTree()
val pos = inSkipToken
if (isSymLit) {
atPos(pos) {
var symid = scalaDot(nme.Symbol)
Apply(symid, List(t))
}
} else {
t
}
}
def newLineOpt() {
if (inToken == NEWLINE) inNextToken
}
def newLinesOpt() {
if (inToken == NEWLINE || inToken == NEWLINES)
inNextToken
}
def newLineOptWhenFollowedBy(token: Int) {
// note: next is defined here because current == NEWLINE
if (inToken == NEWLINE && inNextTokenCode == token) newLineOpt()
}
def newLineOptWhenFollowing(p: Int => Boolean) {
// note: next is defined here because current == NEWLINE
if (inToken == NEWLINE && p(inNextTokenCode)) newLineOpt()
}
/* ------------- TYPES ---------------------------------------------------- */
/** TypedOpt ::= [`:' Type]
*/
def typedOpt(): Tree =
if (inToken == COLON) { inNextToken; typ() }
else TypeTree()
/** RequiresTypedOpt ::= [requires AnnotType]
*/
def requiresTypeOpt(): Tree =
if (inToken == REQUIRES) {
deprecationWarning(in.currentPos, "`requires T' has been deprecated; use `{ self: T => ...' instead")
inNextToken; annotType(false)
} else TypeTree()
/** Types ::= Type {`,' Type}
* (also eats trailing comma if it finds one)
*/
def types(isPattern: Boolean, isTypeApply: Boolean, isFuncArg: Boolean): List[Tree] = {
val ts = new ListBuffer[Tree] + argType(isPattern, isTypeApply, isFuncArg)
while (inToken == COMMA) {
val pos = inCurrentPos
inNextToken
if (inToken == RPAREN) {
deprecationWarning(pos, "Trailing commas have been deprecated")
return ts.toList
} else {
ts += argType(isPattern, isTypeApply, isFuncArg)
}
}
ts.toList
}
/** modes for infix types */
object InfixMode extends Enumeration {
val FirstOp, LeftOp, RightOp = Value
}
/** Type ::= InfixType `=>' Type
* | `(' [`=>' Type] `)' `=>' Type
* | InfixType [ExistentialClause]
* ExistentialClause ::= forSome `{' ExistentialDcl {semi ExistentialDcl}} `}'
* ExistentialDcl ::= type TypeDcl | val ValDcl
*/
def typ(): Tree = typ(false)
def typ(isPattern: Boolean): Tree = placeholderTypeBoundary {
val t =
if (inToken == LPAREN) {
val pos = inSkipToken
if (inToken == RPAREN) {
inNextToken
atPos(accept(ARROW)) { makeFunctionTypeTree(List(), typ(isPattern)) }
} else {
val ts = types(isPattern, false, true)
accept(RPAREN)
if (inToken == ARROW) atPos(inSkipToken) {
makeFunctionTypeTree(ts, typ(isPattern))
}
else {
for (t <- ts) t match {
case AppliedTypeTree(Select(_, n), _)
if (n == nme.BYNAME_PARAM_CLASS_NAME.toTypeName) =>
syntaxError(t.pos, "no by-name parameter type allowed here", false)
case _ =>
}
infixTypeRest(pos, annotTypeRest(pos, isPattern, makeTupleType(ts, true)), false, InfixMode.FirstOp)
}
}
} else {
infixType(isPattern, InfixMode.FirstOp)
}
if (inToken == ARROW)
atPos(inSkipToken) {
makeFunctionTypeTree(List(t), typ(isPattern))
}
else if (inToken == FORSOME)
atPos(inSkipToken) {
val whereClauses = refinement()
for (wc <- whereClauses) {
wc match {
case TypeDef(_, _, _, TypeBoundsTree(_, _)) |
ValDef(_, _, _, EmptyTree) | EmptyTree =>
;
case _ =>
syntaxError(wc.pos, "not a legal existential clause", false)
}
}
ExistentialTypeTree(t, whereClauses)
}
else t
}
/** InfixType ::= CompoundType {id [nl] CompoundType}
*/
def infixType(isPattern: Boolean, mode: InfixMode.Value): Tree = placeholderTypeBoundary {
infixTypeRest(inCurrentPos, infixTypeFirst(isPattern), isPattern, mode)
}
def infixTypeFirst(isPattern: Boolean): Tree =
if (inToken == LBRACE) scalaAnyRefConstr else annotType(isPattern)
def infixTypeRest(pos: Int, t0: Tree, isPattern: Boolean, mode: InfixMode.Value): Tree = {
val t = compoundTypeRest(pos, t0, isPattern)
if (isIdent && inName != nme.STAR) {
val opPos = inCurrentPos
val leftAssoc = treeInfo.isLeftAssoc(inName)
if (mode == InfixMode.LeftOp) checkAssoc(opPos, inName, true)
else if (mode == InfixMode.RightOp) checkAssoc(opPos, inName, false)
val op = ident()
newLineOptWhenFollowing(isTypeIntroToken)
def mkOp(t1: Tree) = atPos(opPos) { AppliedTypeTree(Ident(op.toTypeName), List(t, t1)) }
if (leftAssoc)
infixTypeRest(inCurrentPos, mkOp(compoundType(isPattern)), isPattern, InfixMode.LeftOp)
else
mkOp(infixType(isPattern, InfixMode.RightOp))
} else t
}
/** CompoundType ::= AnnotType {with AnnotType} [Refinement]
* | Refinement
*/
def compoundType(isPattern: Boolean): Tree =
compoundTypeRest(inCurrentPos, infixTypeFirst(isPattern), isPattern)
def compoundTypeRest(pos: Int, t: Tree, isPattern: Boolean): Tree = {
var ts = new ListBuffer[Tree] + t
while (inToken == WITH) {
inNextToken; ts += annotType(isPattern)
}
newLineOptWhenFollowedBy(LBRACE)
atPos(pos) {
if (inToken == LBRACE) {
// Warn if they are attempting to refine Unit; we can't be certain it's
// scala.Unit they're refining because at this point all we have is an
// identifier, but at a later stage we lose the ability to tell an empty
// refinement from no refinement at all. See bug #284.
for (Ident(name) <- ts) name.toString match {
case "Unit" | "scala.Unit" =>
warning("Detected apparent refinement of Unit; are you missing an '=' sign?")
case _ =>
}
CompoundTypeTree(Template(ts.toList, emptyValDef, refinement()))
}
else
makeIntersectionTypeTree(ts.toList)
}
}
/** AnnotType ::= SimpleType {Annotation}
* SimpleType ::= SimpleType TypeArgs
* | SimpleType `#' Id
* | StableId
* | Path `.' type
* | `(' Types [`,'] `)'
* | WildcardType
*/
def annotType(isPattern: Boolean): Tree = placeholderTypeBoundary {
val pos = inCurrentPos
val t: Tree = annotTypeRest(pos, isPattern,
if (inToken == LPAREN) {
inNextToken
val ts = types(isPattern, false, false)
accept(RPAREN)
atPos(pos) { makeTupleType(ts, true) }
} else if (inToken == USCORE) {
wildcardType(in.skipToken)
} else {
val r = path(false, true)
r match {
case SingletonTypeTree(_) => r
case _ => convertToTypeId(r)
}
})
(t /: annotations(false)) (makeAnnotated)
}
def annotTypeRest(pos: Int, isPattern: Boolean, t: Tree): Tree =
if (inToken == HASH) {
inSkipToken
val posId = inCurrentPos
val id = ident
annotTypeRest(pos, isPattern, atPos(posId) { SelectFromTypeTree(t, id.toTypeName) })
} else if (inToken == LBRACKET) {
val usePos = if (t.pos != NoPosition) t.pos else i2p(pos)
annotTypeRest(pos, isPattern, atPos(usePos) { AppliedTypeTree(t, typeArgs(isPattern, false)) })
}
else
t
/** WildcardType ::= `_' TypeBounds
*/
def wildcardType(pos: Int) = {
val pname = freshName(pos, "_$").toTypeName
val param = atPos(pos) { makeSyntheticTypeParam(pname, typeBounds()) }
placeholderTypes = param :: placeholderTypes
Ident(pname) setPos pos
}
/** TypeArgs ::= `[' ArgType {`,' ArgType} `]'
*/
def typeArgs(isPattern: Boolean, isTypeApply: Boolean): List[Tree] = {
accept(LBRACKET)
val ts = types(isPattern, isTypeApply, false)
accept(RBRACKET)
ts
}
/** ArgType ::= Type
*/
def argType(isPattern: Boolean, isTypeApply: Boolean, isFuncArg: Boolean): Tree =
if (isPattern) {
if (inToken == USCORE)
if (inToken == SUBTYPE || inToken == SUPERTYPE) wildcardType(inSkipToken)
else atPos(inSkipToken) { Bind(nme.WILDCARD.toTypeName, EmptyTree) }
else if (inToken == IDENTIFIER && treeInfo.isVariableName(inName.toTypeName))
atPos(inCurrentPos) {
Bind(ident().toTypeName, EmptyTree)
}
else {
typ(true)
}
} else if (isFuncArg) {
// copy-paste (with change) from def paramType
if (inToken == ARROW)
atPos(inSkipToken) {
AppliedTypeTree(
rootScalaDot(nme.BYNAME_PARAM_CLASS_NAME.toTypeName), List(typ()))
}
else {
val t = typ()
if (isIdent && inName == STAR) {
inNextToken
atPos(t.pos) {
AppliedTypeTree(
rootScalaDot(nme.REPEATED_PARAM_CLASS_NAME.toTypeName), List(t))
}
} else t
}
} else if (isTypeApply) {
typ()
} else {
typ()
}
/* ----------- EXPRESSIONS ------------------------------------------------ */
/** EqualsExpr ::= `=' Expr
*/
def equalsExpr(): Tree = {
accept(EQUALS)
expr()
}
/** Exprs ::= Expr {`,' Expr}
*
* (also eats trailing comma if it finds one)
*/
def exprs(): List[Tree] = {
val ts = new ListBuffer[Tree] + expr()
while (inToken == COMMA) {
val pos = in.currentPos
inNextToken
if (inToken == RPAREN) {
deprecationWarning(pos, "Trailing commas have been deprecated")
return ts.toList
} else {
ts += expr()
}
}
ts.toList
}
/** Expr ::= (Bindings | Id | `_') `=>' Expr
* | Expr1
* ResultExpr ::= (Bindings | Id `:' CompoundType) `=>' Block
* | Expr1
* Expr1 ::= if `(' Expr `)' {nl} Expr [[semi] else Expr]
* | try (`{' Block `}' | Expr) [catch `{' CaseClauses `}'] [finally Expr]
* | while `(' Expr `)' {nl} Expr
* | do Expr [semi] while `(' Expr `)'
* | for (`(' Enumerators `)' | '{' Enumerators '}') {nl} [yield] Expr
* | throw Expr
* | return [Expr]
* | [SimpleExpr `.'] Id `=' Expr
* | SimpleExpr1 ArgumentExprs `=' Expr
* | PostfixExpr Ascription
* | PostfixExpr match `{' CaseClauses `}'
* Bindings ::= `(' [Binding {`,' Binding}] `)'
* Binding ::= (Id | `_') [`:' Type]
* Ascription ::= `:' CompoundType
* | `:' Annotation {Annotation}
* | `:' `_' `*'
*/
def expr(): Tree = expr(Local)
/* hook for IDE, unlike expression can be stubbed
* don't use for any tree that can be inspected in the parser!
*/
def statement(location: Int): Tree = expr(location)
def expr(location: Int): Tree = {
def isWildcard(t: Tree): Boolean = t match {
case Ident(name1) if !placeholderParams.isEmpty && name1 == placeholderParams.head.name => true
case Typed(t1, _) => isWildcard(t1)
case Annotated(t1, _) => isWildcard(t1)
case _ => false
}
var savedPlaceholderParams = placeholderParams
placeholderParams = List()
var res = inToken match {
case IF =>
val pos = inSkipToken
val cond = surround(LPAREN,RPAREN)(expr(),Literal(true))
newLinesOpt()
val thenp = expr()
val elsep = if (inToken == ELSE) { inNextToken; expr() }
else Literal(())
atPos(pos) { If(cond, thenp, elsep) }
case TRY =>
atPos(inSkipToken) {
val body =
if (inToken == LBRACE) surround(LBRACE, RBRACE)(block(), Literal(()))
else if (inToken == LPAREN) surround(LPAREN, RPAREN)(expr(), Literal(()))
else expr()
val catches =
if (inToken == CATCH) {
inNextToken
val cases = surround(LBRACE,RBRACE)(caseClauses(), Nil)
cases
} else Nil
val finalizer =
if (inToken == FINALLY) { inNextToken; expr() }
else EmptyTree
Try(body, catches, finalizer)
}
case WHILE =>
val pos = inSkipToken
val lname: Name = freshName(pos, "while$")
val cond = surround(LPAREN,RPAREN)(expr(),Literal(true))
newLinesOpt()
val body = expr()
atPos(pos) { makeWhile(lname, cond, body) }
case DO =>
val pos = inSkipToken
val lname: Name = freshName(pos, "doWhile$")
val body = expr()
if (isStatSep) inNextToken
accept(WHILE)
val cond = surround(LPAREN,RPAREN)(expr(), Literal(true))
atPos(pos) { makeDoWhile(lname, body, cond) }
case FOR =>
atPos(inSkipToken) {
val startToken = inToken
val (open,close) = if (startToken == LBRACE) (LBRACE,RBRACE) else (LPAREN,RPAREN)
val enums = surround(open,close)(enumerators(), Nil)
newLinesOpt()
if (inToken == YIELD) {
inNextToken; makeForYield(enums, expr())
} else makeFor(enums, expr())
}
case RETURN =>
atPos(inSkipToken) {
Return(if (isExprIntro) expr() else Literal(()))
}
case THROW =>
atPos(inSkipToken) {
Throw(expr())
}
case DOT =>
deprecationWarning(in.currentPos, "`.f' has been deprecated; use `_.f' instead")
atPos(inSkipToken) {
if (isIdent) {
makeDotClosure(stripParens(simpleExpr()))
} else {
syntaxErrorOrIncomplete("identifier expected", true)
errorTermTree
}
}
case _ =>
var t = postfixExpr()
if (inToken == EQUALS) {
t match {
case Ident(_) | Select(_, _) | Apply(_, _) =>
t = atPos(inSkipToken) { makeAssign(t, expr()) }
case _ =>
}
} else if (inToken == COLON) {
t = stripParens(t)
val pos = inSkipToken
if (inToken == USCORE) {
//todo: need to handle case where USCORE is a wildcard in a type
val pos1 = inSkipToken
if (isIdent && inName == nme.STAR) {
inNextToken
t = atPos(pos) {
Typed(t, atPos(pos1) { Ident(nme.WILDCARD_STAR.toTypeName) })
}
} else {
syntaxErrorOrIncomplete("`*' expected", true)
}
} else if (in.token == AT) {
t = (t /: annotations(false)) (makeAnnotated)
} else {
t = atPos(pos) {
val tpt =
if (location != Local) infixType(false, InfixMode.FirstOp)
else typ()
if (isWildcard(t))
(placeholderParams: @unchecked) match {
case (vd @ ValDef(mods, name, _, _)) :: rest =>
placeholderParams = copy.ValDef(vd, mods, name, tpt.duplicate, EmptyTree) :: rest
}
// this does not correspond to syntax, but is necessary to
// accept closures. We might restrict closures to be between {...} only!
Typed(t, tpt)
}
}
} else if (inToken == MATCH) {
t = atPos(inSkipToken) {
val cases = surround(LBRACE,RBRACE)(caseClauses(), Nil)
Match(stripParens(t), cases)
}
}
// in order to allow anonymous functions as statements (as opposed to expressions) inside
// templates, we have to disambiguate them from self type declarations - bug #1565
// The case still missed is unparenthesized single argument, like "x: Int => x + 1", which
// may be impossible to distinguish from a self-type and so remains an error. (See #1564)
def lhsIsTypedParamList() = t match {
case Parens(xs) if xs forall (_.isInstanceOf[Typed]) => true
case _ => false
}
if (inToken == ARROW && (location != InTemplate || lhsIsTypedParamList)) {
t = atPos(inSkipToken) {
Function(convertToParams(t), if (location != InBlock) expr() else block())
}
}
stripParens(t)
}
if (!placeholderParams.isEmpty && !isWildcard(res)) {
res = atPos(res.pos){ Function(placeholderParams.reverse, res) }
placeholderParams = List()
}
placeholderParams = placeholderParams ::: savedPlaceholderParams
res
}
/** PostfixExpr ::= InfixExpr [Id [nl]]
* InfixExpr ::= PrefixExpr
* | InfixExpr Id [nl] InfixExpr
*/
def postfixExpr(): Tree = {
val base = opstack
var top = prefixExpr()
while (isIdent) {
top = reduceStack(
true, base, top, precedence(inName), treeInfo.isLeftAssoc(inName))
val op = inName
opstack = OpInfo(top, op, inCurrentPos) :: opstack
ident()
newLineOptWhenFollowing(isExprIntroToken)
if (isExprIntro) {
top = prefixExpr()
} else {
val topinfo = opstack.head
opstack = opstack.tail
return Select(
stripParens(reduceStack(true, base, topinfo.operand, 0, true)),
topinfo.operator.encode).setPos(topinfo.pos)
}
}
reduceStack(true, base, top, 0, true)
}
/** PrefixExpr ::= [`-' | `+' | `~' | `!' | `&'] SimpleExpr
*/
def prefixExpr(): Tree = {
def unaryOp(): Name = "unary_" + ident()
if (isIdent && inName == MINUS) {
val name = unaryOp()
inToken match {
case INTLIT | LONGLIT | FLOATLIT | DOUBLELIT => literal(false, true)
case _ => atPos(inCurrentPos) { Select(stripParens(simpleExpr()), name) }
}
} else if (isIdent && (inName == PLUS || inName == TILDE || inName == BANG)) {
val pos = inCurrentPos
val name = unaryOp()
atPos(pos) { Select(stripParens(simpleExpr()), name) }
} else if (isIdent && inName == AMP) {
deprecationWarning(in.currentPos, "`&f' has been deprecated; use `f _' instead")
val pos = inCurrentPos
val name = ident()
atPos(pos) { Typed(stripParens(simpleExpr()), Function(List(), EmptyTree)) }
/* XX-LIFTING
} else if (settings.Xexperimental.value && isIdent && inName == SLASH) {
val pos = inSkipToken
val name = freshName()
liftedGenerators += ValFrom(pos, Bind(name, Ident(nme.WILDCARD)), simpleExpr())
Ident(name) setPos pos
*/
} else {
simpleExpr()
}
}
def xmlLiteral(): Tree
/* SimpleExpr ::= new (ClassTemplate | TemplateBody)
* | BlockExpr
* | SimpleExpr1 [`_']
* SimpleExpr1 ::= literal
* | xLiteral
* | Path
* | `(' [Exprs [`,']] `)'
* | SimpleExpr `.' Id
* | SimpleExpr TypeArgs
* | SimpleExpr1 ArgumentExprs
*/
def simpleExpr(): Tree = {
var t: Tree = null
var canApply = true
inToken match {
case CHARLIT | INTLIT | LONGLIT | FLOATLIT | DOUBLELIT | STRINGLIT |
SYMBOLLIT | TRUE | FALSE | NULL =>
t = literal(false, false)
case XMLSTART => t = xmlLiteral()
case IDENTIFIER | BACKQUOTED_IDENT | THIS | SUPER =>
t = path(true, false)
case USCORE =>
val pos = inSkipToken
val pname = freshName(pos, "x$")
val param = atPos(pos){ makeSyntheticParam(pname) }
placeholderParams = param :: placeholderParams
t = atPos(pos) { Ident(pname) }
case LPAREN =>
val pos = inSkipToken
val ts = if (inToken == RPAREN) List() else exprs()
accept(RPAREN)
t = Parens(ts) setPos (pos)
case LBRACE =>
t = blockExpr()
canApply = false
case NEW =>
t = atPos(inSkipToken) {
val (parents, argss, self, stats) = template(false)
makeNew(parents, self, stats, argss)
}
canApply = false
case _ =>
syntaxErrorOrIncomplete("illegal start of simple expression", true)
t = errorTermTree
}
simpleExprRest(t, canApply)
}
def simpleExprRest(t: Tree, canApply: Boolean): Tree = {
if (canApply) newLineOptWhenFollowedBy(LBRACE)
inToken match {
case DOT =>
simpleExprRest(atPos(inSkipToken) { selector(stripParens(t)) }, true)
case LBRACKET =>
val t1 = stripParens(t)
t1 match {
case Ident(_) | Select(_, _) =>
val pos = if (t1.pos == NoPosition) i2p(inCurrentPos) else t1.pos
simpleExprRest(atPos(pos) { TypeApply(t1, typeArgs(false, true)) }, true)
case _ =>
t1
}
case LPAREN | LBRACE if (canApply) =>
// again, position should be on idetifier, not (
var pos = if (t.pos == NoPosition) i2p(inCurrentPos) else t.pos
simpleExprRest(atPos(pos) {
// look for anonymous function application like (f _)(x) and
// translate to (f _).apply(x), bug #460
val sel = t match {
case Parens(List(Typed(_, _: Function))) =>
Select(stripParens(t), nme.apply)
case _ =>
stripParens(t)
}
Apply(sel, argumentExprs())
}, true)
case USCORE =>
atPos(inSkipToken) { Typed(stripParens(t), Function(List(), EmptyTree)) }
case _ =>
t
}
}
/** ArgumentExprs ::= `(' [Exprs [`,']] `)'
* | [nl] BlockExpr
*/
def argumentExprs(): List[Tree] = {
if (inToken == LBRACE) {
List(blockExpr())
} else {
val ts = surround(LPAREN,RPAREN)(if (inToken == RPAREN) List() else exprs(), List())
ts
}
}
/** BlockExpr ::= `{' (CaseClauses | Block) `}'
*/
def blockExpr(): Tree = {
assert(inToken == LBRACE)
val res = atPos(accept(LBRACE)) { // no need to surround
if (inToken == CASE) Match(EmptyTree, caseClauses())
else block()
}
accept(RBRACE)
res
}
/** Block ::= BlockStatSeq
*/
def block(): Tree =
makeBlock(blockStatSeq(new ListBuffer[Tree]))
/** CaseClauses ::= CaseClause {CaseClause}
*/
def caseClauses(): List[CaseDef] = {
val ts = new ListBuffer[CaseDef]
do { ts += caseClause()
} while (inToken == CASE)
ts.toList
}
/** CaseClause ::= case Pattern [Guard] `=>' Block
*/
def caseClause(): CaseDef =
atPos(accept(CASE)) {
val pat = pattern()
val gd = guard()
makeCaseDef(pat, gd, caseBlock())
}
// IDE HOOK (so we can memoize case blocks)
def caseBlock(): Tree =
atPos(accept(ARROW))(block())
/** Guard ::= if PostfixExpr
*/
def guard(): Tree =
if (inToken == IF) { inNextToken; stripParens(postfixExpr()) }
else EmptyTree
/** Enumerators ::= Generator {semi Enumerator}
* Enumerator ::= Generator
* | Guard
* | val Pattern1 `=' Expr
*/
def enumerators(): List[Enumerator] = {
val newStyle = inToken != VAL // todo: deprecate old style
//if (!newStyle)
// deprecationWarning(inCurrentPos, "for (val x <- ... ) has been deprecated; use for (x <- ... ) instead")
val enums = new ListBuffer[Enumerator]
generator(enums, false)
while (isStatSep) {
inNextToken
if (newStyle) {
if (inToken == IF) enums += Filter(guard())
else generator(enums, true)
} else {
if (inToken == VAL) generator(enums, true)
else enums += Filter(expr())
}
}
enums.toList
}
/** Generator ::= Pattern1 (`<-' | '=') Expr [Guard]
*/
def generator(enums: ListBuffer[Enumerator], eqOK: Boolean) {
if (inToken == VAL) inNextToken
val pos = inCurrentPos;
val pat = pattern1(false)
val tok = inToken
if (tok == EQUALS && eqOK) inNextToken
else accept(LARROW)
enums += makeGenerator(pos, pat, tok == EQUALS, expr)
if (inToken == IF) enums += Filter(guard())
}
//def p2i(pos : ScanPosition) : Int;
/* -------- PATTERNS ------------------------------------------- */
/** Patterns ::= Pattern { `,' Pattern }
* SeqPatterns ::= SeqPattern { `,' SeqPattern }
*
* (also eats trailing comma if it finds one)
*/
def patterns(seqOK: Boolean): List[Tree] = {
val ts = new ListBuffer[Tree] + pattern(seqOK)
while (inToken == COMMA) {
val pos = inCurrentPos
inNextToken
if (inToken == RPAREN) {
deprecationWarning(pos, "Trailing commas have been deprecated")
return ts.toList
} else {
ts += pattern(seqOK)
}
}
ts.toList
}
/** Pattern ::= Pattern1 { `|' Pattern1 }
* SeqPattern ::= SeqPattern1 { `|' SeqPattern1 }
*/
def pattern(seqOK: Boolean): Tree = {
val pos = inCurrentPos
val t = pattern1(seqOK)
if (isIdent && inName == BAR) {
val ts = new ListBuffer[Tree] + t
while (isIdent && inName == BAR) {
inNextToken; ts += pattern1(seqOK)
}
atPos(pos) { makeAlternative(ts.toList) }
} else t
}
def pattern(): Tree = pattern(false)
/** Pattern1 ::= varid `:' TypePat
* | `_' `:' TypePat
* | Pattern2
* SeqPattern1 ::= varid `:' TypePat
* | `_' `:' TypePat
* | [SeqPattern2]
*/
def pattern1(seqOK: Boolean): Tree = {
//if (false && /*disabled, no regexp matching*/ seqOK && !isExprIntro) {
//atPos(inCurrentPos) { Sequence(List()) }
//} else {
val p = pattern2(seqOK)
p match {
case Ident(name) if (treeInfo.isVarPattern(p) && inToken == COLON) =>
atPos(inSkipToken) { Typed(p, compoundType(true)) }
case _ =>
p
}
//}
}
/* Pattern2 ::= varid [ @ Pattern3 ]
* | Pattern3
* SeqPattern2 ::= varid [ @ SeqPattern3 ]
* | SeqPattern3
*/
def pattern2(seqOK: Boolean): Tree = {
val p = pattern3(seqOK)
if (inToken == AT) {
p match {
case Ident(name) =>
if (name == nme.WILDCARD) {
inNextToken; pattern3(seqOK)
} else if (treeInfo.isVarPattern(p)) {
inNextToken
atPos(p.pos) { Bind(name, pattern3(seqOK)) }
} else {
p
}
case _ =>
p
}
} else p
}
/* Pattern3 ::= SimplePattern
* | SimplePattern {Id [nl] SimplePattern}
* SeqPattern3 ::= SeqSimplePattern [ '*' | '?' | '+' ]
* | SeqSimplePattern {Id [nl] SeqSimplePattern}
*/
def pattern3(seqOK: Boolean): Tree = {
val base = opstack
var top = simplePattern(seqOK)
if (seqOK && isIdent && inName == STAR)
return atPos(inSkipToken)(Star(stripParens(top)))
while (isIdent && inName != BAR) {
top = reduceStack(
false, base, top, precedence(inName), treeInfo.isLeftAssoc(inName))
val op = inName
opstack = OpInfo(top, op, inCurrentPos) :: opstack
ident()
top = simplePattern(seqOK)
}
stripParens(reduceStack(false, base, top, 0, true))
}
def xmlLiteralPattern(): Tree
/** SimplePattern ::= varid
* | `_'
* | literal
* | XmlPattern
* | StableId [TypeArgs] [`(' [SeqPatterns [`,']] `)']
* | `(' [Patterns [`,']] `)'
* SimpleSeqPattern ::= varid
* | `_'
* | literal
* | XmlPattern
* | `<' xLiteralPattern
* | StableId [TypeArgs] [`(' [SeqPatterns [`,']] `)']
* | `(' [SeqPatterns [`,']] `)'
*
* XXX: Hook for IDE
*/
def simplePattern(seqOK: Boolean): Tree = inToken match {
case IDENTIFIER | BACKQUOTED_IDENT | THIS =>
var t = stableId()
inToken match {
case INTLIT | LONGLIT | FLOATLIT | DOUBLELIT =>
t match {
case Ident(name) if name == nme.MINUS =>
return literal(true, true)
case _ =>
}
case _ =>
}
/* not yet
if (inToken == LBRACKET)
atPos(inCurrentPos) {
val ts = typeArgs(true, false)
accept(LPAREN)
val ps = if (inToken == RPAREN) List() else patterns(true, false)
accept(RPAREN)
Apply(TypeApply(convertToTypeId(t), ts), ps)
}
else */
if (inToken == LPAREN) {
atPos(t.pos) { Apply(t, argumentPatterns()) }
} else t
case USCORE =>
atPos(inSkipToken) { Ident(nme.WILDCARD) }
case CHARLIT | INTLIT | LONGLIT | FLOATLIT | DOUBLELIT |
STRINGLIT | SYMBOLLIT | TRUE | FALSE | NULL =>
literal(true, false)
case LPAREN =>
val pos = inSkipToken
val ps = if (inToken == RPAREN) List() else patterns(false)
accept(RPAREN)
Parens(ps) setPos (pos)
case XMLSTART =>
xmlLiteralPattern()
case _ =>
syntaxErrorOrIncomplete("illegal start of simple pattern", true)
errorPatternTree
}
def argumentPatterns(): List[Tree] = {
accept(LPAREN)
val ps = if (inToken == RPAREN) List() else patterns(true)
accept(RPAREN)
ps
}
/* -------- MODIFIERS and ANNOTATIONS ------------------------------------------- */
private def normalize(mods: Modifiers): Modifiers =
if ((mods hasFlag Flags.PRIVATE) && mods.privateWithin != nme.EMPTY.toTypeName)
mods &~ Flags.PRIVATE
else if ((mods hasFlag Flags.ABSTRACT) && (mods hasFlag Flags.OVERRIDE))
mods &~ (Flags.ABSTRACT | Flags.OVERRIDE) | Flags.ABSOVERRIDE
else
mods
private def addMod(mods: Modifiers, mod: Long): Modifiers = {
if (mods hasFlag mod) syntaxError(inCurrentPos, "repeated modifier", false)
inNextToken
mods | mod
}
/** AccessQualifier ::= "[" (Id | this) "]"
*/
def accessQualifierOpt(mods: Modifiers): Modifiers = {
var result = mods
if (inToken == LBRACKET) {
inNextToken
if (mods.privateWithin != nme.EMPTY.toTypeName)
syntaxError("duplicate private/protected qualifier", false)
result = if (inToken == THIS) { inNextToken; mods | Flags.LOCAL }
else Modifiers(mods.flags, ident().toTypeName)
accept(RBRACKET)
}
result
}
/** AccessModifier ::= (private | protected) [AccessQualifier]
*/
def accessModifierOpt(): Modifiers = normalize {
inToken match {
case PRIVATE => inNextToken; accessQualifierOpt(Modifiers(Flags.PRIVATE))
case PROTECTED => inNextToken; accessQualifierOpt(Modifiers(Flags.PROTECTED))
case _ => NoMods
}
}
/** Modifiers ::= {Modifier}
* Modifier ::= LocalModifier
* | AccessModifier
* | override
*/
def modifiers(): Modifiers = normalize {
def loop(mods: Modifiers): Modifiers = inToken match {
case ABSTRACT =>
loop(addMod(mods, Flags.ABSTRACT))
case FINAL =>
loop(addMod(mods, Flags.FINAL))
case SEALED =>
loop(addMod(mods, Flags.SEALED))
case PRIVATE =>
loop(accessQualifierOpt(addMod(mods, Flags.PRIVATE)))
case PROTECTED =>
loop(accessQualifierOpt(addMod(mods, Flags.PROTECTED)))
case OVERRIDE =>
loop(addMod(mods, Flags.OVERRIDE))
case IMPLICIT =>
loop(addMod(mods, Flags.IMPLICIT))
case LAZY =>
loop(addMod(mods, Flags.LAZY))
case NEWLINE =>
inNextToken
loop(mods)
case _ =>
mods
}
loop(NoMods)
}
/** LocalModifiers ::= {LocalModifier}
* LocalModifier ::= abstract | final | sealed | implicit | lazy
*/
def localModifiers(): Modifiers = {
def loop(mods: Modifiers): Modifiers = inToken match {
case ABSTRACT =>
loop(addMod(mods, Flags.ABSTRACT))
case FINAL =>
loop(addMod(mods, Flags.FINAL))
case SEALED =>
loop(addMod(mods, Flags.SEALED))
case IMPLICIT =>
loop(addMod(mods, Flags.IMPLICIT))
case LAZY =>
loop(addMod(mods, Flags.LAZY))
case _ =>
mods
}
loop(NoMods)
}
/** Annotations ::= {Annotation [nl]}
* Annotation ::= `@' AnnotationExpr
*/
def annotations(skipNewLines: Boolean): List[Annotation] = {
var annots = new ListBuffer[Annotation]
while (inToken == AT) {
inNextToken
annots += annotationExpr()
if (skipNewLines) newLineOpt()
}
annots.toList
}
/** AnnotationExpr ::= StableId [TypeArgs] [`(' [Exprs] `)'] [[nl] `{' {NameValuePair} `}']
* NameValuePair ::= val id `=' PrefixExpr
*/
def annotationExpr(): Annotation = {
def nameValuePair(): Tree = {
var pos = inCurrentPos
accept(VAL)
val aname = ident()
accept(EQUALS)
val rhs = stripParens(prefixExpr())
atPos(pos) { ValDef(NoMods, aname, TypeTree(), rhs) }
}
val pos = inCurrentPos
var t: Tree = convertToTypeId(stableId())
if (inToken == LBRACKET)
t = atPos(inCurrentPos)(AppliedTypeTree(t, typeArgs(false, false)))
val args = if (inToken == LPAREN) argumentExprs() else List()
newLineOptWhenFollowedBy(LBRACE)
val nameValuePairs: List[Tree] = if (inToken == LBRACE) {
inNextToken
val nvps = new ListBuffer[Tree] + nameValuePair()
while (inToken == COMMA) {
inNextToken
nvps += nameValuePair()
}
accept(RBRACE)
nvps.toList
} else List()
val constr = atPos(pos) { New(t, List(args)) }
Annotation(constr, nameValuePairs) setPos pos
}
/* -------- PARAMETERS ------------------------------------------- */
/** ParamClauses ::= {ParamClause} [[nl] `(' implicit Params `)']
* ParamClause ::= [nl] `(' [Params] ')'
* Params ::= Param {`,' Param}
* Param ::= {Annotation} Id [`:' ParamType]
* ClassParamClauses ::= {ClassParamClause} [[nl] `(' implicit ClassParams `)']
* ClassParamClause ::= [nl] `(' [ClassParams] ')'
* ClassParams ::= ClassParam {`,' ClassParam}
* ClassParam ::= {Annotation} [{Modifier} (`val' | `var')] Id [`:' ParamType]
*/
def paramClauses(owner: Name, implicitViews: List[Tree], ofCaseClass: Boolean): List[List[ValDef]] = {
var implicitmod = 0
var caseParam = ofCaseClass
def param(): ValDef = {
var pos = inCurrentPos
{
val annots = annotations(false)
var mods = Modifiers(Flags.PARAM)
if (owner.isTypeName) {
mods = modifiers() | Flags.PARAMACCESSOR
if (mods.hasFlag(Flags.LAZY)) syntaxError("lazy modifier not allowed here. Use call-by-name parameters instead", false)
if (inToken == VAL) {
inNextToken
} else if (inToken == VAR) {
mods = mods | Flags.MUTABLE
inNextToken
} else {
if (mods.flags != Flags.PARAMACCESSOR) accept(VAL)
if (!(caseParam)) mods = mods | Flags.PRIVATE | Flags.LOCAL
}
if (caseParam) mods = mods | Flags.CASEACCESSOR
}
val namePos = inCurrentPos
val name = ident()
if (name != nme.ERROR) pos = namePos
var bynamemod = 0
val tpt =
if (settings.Xexperimental.value && !owner.isTypeName && inToken != COLON) {
TypeTree()
} else { // XX-METHOD-INFER
accept(COLON)
if (inToken == ARROW) {
if (owner.isTypeName && !mods.hasFlag(Flags.LOCAL))
syntaxError(
inCurrentPos,
(if (mods.hasFlag(Flags.MUTABLE)) "`var'" else "`val'") +
" parameters may not be call-by-name", false)
else bynamemod = Flags.BYNAMEPARAM
}
paramType()
}
atPos(pos){
ValDef((mods | implicitmod | bynamemod) withAnnotations annots, name, tpt, EmptyTree)
}
}
}
def paramClause(): List[ValDef] = {
val params = new ListBuffer[ValDef]
if (inToken != RPAREN) {
if (inToken == IMPLICIT) {
if (!implicitViews.isEmpty)
syntaxError("cannot have both view bounds `<%' and implicit parameters", false)
inNextToken
implicitmod = Flags.IMPLICIT
}
params += param()
while (inToken == COMMA) {
inNextToken; params += param()
}
}
params.toList
}
val vds = new ListBuffer[List[ValDef]]
val pos = inCurrentPos
newLineOptWhenFollowedBy(LPAREN)
if (ofCaseClass && inToken != LPAREN)
deprecationWarning(in.currentPos, "case classes without a parameter list have been deprecated;\n"+
"use either case objects or case classes with `()' as parameter list.")
while (implicitmod == 0 && inToken == LPAREN) {
inNextToken
vds += paramClause()
accept(RPAREN)
caseParam = false
newLineOptWhenFollowedBy(LPAREN)
}
val result = vds.toList
if (owner == nme.CONSTRUCTOR &&
(result.isEmpty ||
(!result.head.isEmpty && result.head.head.mods.hasFlag(Flags.IMPLICIT))))
if (inToken == LBRACKET)
syntaxError(pos, "no type parameters allowed here", false)
else if(inToken == EOF)
incompleteInputError("auxiliary constructor needs non-implicit parameter list")
else
syntaxError(pos, "auxiliary constructor needs non-implicit parameter list", false)
addImplicitViews(owner, result, implicitViews)
}
/** ParamType ::= Type | `=>' Type | Type `*'
*/
def paramType(): Tree =
if (inToken == ARROW)
atPos(inSkipToken) {
AppliedTypeTree(
rootScalaDot(nme.BYNAME_PARAM_CLASS_NAME.toTypeName), List(typ()))
}
else {
val t = typ()
if (isIdent && inName == STAR) {
inNextToken
atPos(t.pos) {
AppliedTypeTree(
rootScalaDot(nme.REPEATED_PARAM_CLASS_NAME.toTypeName), List(t))
}
} else t
}
/** TypeParamClauseOpt ::= [TypeParamClause]
* TypeParamClause ::= `[' VariantTypeParam {`,' VariantTypeParam} `]']
* VariantTypeParam ::= [`+' | `-'] TypeParam
* FunTypeParamClauseOpt ::= [FunTypeParamClause]
* FunTypeParamClause ::= `[' TypeParam {`,' TypeParam} `]']
* TypeParam ::= Id TypeParamClauseOpt TypeBounds [<% Type]
*/
def typeParamClauseOpt(owner: Name, implicitViewBuf: ListBuffer[Tree]): List[TypeDef] = {
def typeParam(): TypeDef = {
var mods = Modifiers(Flags.PARAM)
if (owner.isTypeName && isIdent) {
if (inName == PLUS) {
inNextToken
mods = mods | Flags.COVARIANT
} else if (inName == MINUS) {
inNextToken
mods = mods | Flags.CONTRAVARIANT
}
}
val pos = inCurrentPos
val pname =
(if (inToken == USCORE) { // @M! also allow underscore
inNextToken
nme.WILDCARD
} else ident()).toTypeName
val tparams = typeParamClauseOpt(pname, null) // @M TODO null --> no higher-order view bounds for now
val param = atPos(pos) { TypeDef(mods, pname, tparams, typeBounds()) }
if (inToken == VIEWBOUND && (implicitViewBuf ne null))
implicitViewBuf += atPos(inSkipToken) {
makeFunctionTypeTree(List(Ident(pname)), typ())
}
param
}
val params = new ListBuffer[TypeDef]
newLineOptWhenFollowedBy(LBRACKET)
if (inToken == LBRACKET) {
inNextToken
params += typeParam()
while (inToken == COMMA) {
inNextToken
params += typeParam()
}
accept(RBRACKET)
}
params.toList
}
/** TypeBounds ::= [`>:' Type] [`<:' Type]
*/
def typeBounds(): TypeBoundsTree =
TypeBoundsTree(
bound(SUPERTYPE, nme.Nothing),
bound(SUBTYPE, nme.Any))
def bound(tok: Int, default: Name): Tree =
if (inToken == tok) { inNextToken; typ() }
else rootScalaDot(default.toTypeName)
/* -------- DEFS ------------------------------------------- */
/** Import ::= import ImportExpr {`,' ImportExpr}
*/
def importClause(): List[Tree] = {
accept(IMPORT)
val ts = new ListBuffer[Tree] + importExpr()
while (inToken == COMMA) {
inNextToken; ts += importExpr()
}
ts.toList
}
/** ImportExpr ::= StableId `.' (Id | `_' | ImportSelectors)
* XXX: Hook for IDE
*/
def importExpr(): Tree =
atPos(inCurrentPos) {
var t: Tree = null
//var pos : ScanPosition = null.asInstanceOf[ScanPosition]
var pos : Int = -1
if (inToken == THIS) {
t = atPos(inCurrentPos) { This(nme.EMPTY.toTypeName) }
t = atPos(accept(DOT)) { selector(t) }
pos = accept(DOT)
} else {
val i = atPos(inCurrentPos) { Ident(ident()) }
pos = accept(DOT)
if (inToken == THIS) {
inNextToken
t = atPos(i.pos) { This(i.name.toTypeName) }
t = atPos(accept(DOT)) { selector(t) }
pos = accept(DOT)
} else {
t = i
}
}
def loop: Tree =
if (inToken == USCORE) {
inNextToken
Import(t, List((nme.WILDCARD, null)))
} else if (inToken == LBRACE) {
Import(t, importSelectors())
} else {
val identPos = inCurrentPos
val name = ident() // @S: use position of identifier, not dot!
pos = if (name == nme.ERROR) pos else identPos
if (inToken == DOT) {
t = atPos(pos) { Select(t, name) }
pos = accept(DOT)
loop
} else {
Import(t, List((name, name)))
}
}
loop
}
/** ImportSelectors ::= `{' {ImportSelector `,'} (ImportSelector | `_') `}'
*/
def importSelectors(): List[(Name, Name)] = {
val names = new ListBuffer[(Name, Name)]
accept(LBRACE)
var isLast = importSelector(names)
while (!isLast && inToken == COMMA) {
inNextToken
isLast = importSelector(names)
}
accept(RBRACE)
names.toList
}
/** ImportSelector ::= Id [`=>' Id | `=>' `_']
*/
def importSelector(names: ListBuffer[(Name, Name)]): Boolean =
if (inToken == USCORE) {
inNextToken; names += ((nme.WILDCARD, null)); true
} else {
val name = ident()
names += ((
name,
if (inToken == ARROW) {
inNextToken
if (inToken == USCORE) { inNextToken; nme.WILDCARD } else ident()
} else {
name
}))
false
}
/** Def ::= val PatDef
* | var VarDef
* | def FunDef
* | type [nl] TypeDef
* | TmplDef
* Dcl ::= val ValDcl
* | var ValDcl
* | def FunDcl
* | type [nl] TypeDcl
*/
def defOrDcl(mods: Modifiers): List[Tree] = {
if ((mods hasFlag Flags.LAZY) && in.token != VAL)
syntaxError("lazy not allowed here. Only vals can be lazy", false)
inToken match {
case VAL =>
patDefOrDcl(mods)
case VAR =>
patDefOrDcl(mods | Flags.MUTABLE)
case DEF =>
List(funDefOrDcl(mods))
case TYPE =>
inNextToken
newLinesOpt()
List(typeDefOrDcl(mods))
case _ =>
List(tmplDef(mods))
}
}
/** IDE hook: for non-local defs or dcls with modifiers and annotations */
def nonLocalDefOrDcl : List[Tree] = {
val annots = annotations(true)
defOrDcl(modifiers() withAnnotations annots)
}
/** not hooked by the IDE, will not undergo stubbing. Used for early initialization blocks. */
def preNonLocalDefOrDcl : List[Tree] = {
val annots = annotations(true)
defOrDcl(modifiers() withAnnotations annots)
}
/** PatDef ::= Pattern2 {`,' Pattern2} [`:' Type] `=' Expr
* ValDcl ::= Id {`,' Id} `:' Type
* VarDef ::= PatDef | Id {`,' Id} `:' Type `=' `_'
*/
def patDefOrDcl(mods: Modifiers): List[Tree] = {
var newmods = mods
val lhsBuf = new ListBuffer[Tree]
do {
inNextToken
val p = pattern2(false)
lhsBuf += stripParens(p)
} while (inToken == COMMA)
val lhs = lhsBuf.toList
val tp = typedOpt()
val rhs =
if (tp.isEmpty || inToken == EQUALS) {
accept(EQUALS)
if (!tp.isEmpty && newmods.hasFlag(Flags.MUTABLE) &&
(lhs.toList forall (_.isInstanceOf[Ident])) && inToken == USCORE) {
inNextToken
newmods = newmods | Flags.DEFAULTINIT
EmptyTree
} else {
expr()
}
} else {
newmods = newmods | Flags.DEFERRED
EmptyTree
}
var originalUsed = false
def mkDefs(p: Tree): List[Tree] = {
//Console.println("DEBUG: p = "+p.toString()); // DEBUG
val trees =
makePatDef(newmods,
if (tp.isEmpty)
p
else
Typed(p, tp),
if (inIDE && !originalUsed) {
// because duplicates have weaker status than originals
// need an original.
originalUsed = true
rhs
} else rhs.duplicate) map atPos(p.pos)
if (newmods.hasFlag(Flags.DEFERRED)) {
trees match {
case List(ValDef(_, _, _, EmptyTree)) =>
if (mods.hasFlag(Flags.LAZY))
syntaxError(p.pos, "lazy values may not be abstract", false)
case _ => syntaxError(p.pos, "pattern definition may not be abstract", false)
}
}
trees
}
for (p <- lhs.toList; d <- mkDefs(p)) yield d
}
/** VarDef ::= PatDef
* | Id {`,' Id} `:' Type `=' `_'
* VarDcl ::= Id {`,' Id} `:' Type
def varDefOrDcl(mods: Modifiers): List[Tree] = {
var newmods = mods | Flags.MUTABLE
val lhs = new ListBuffer[(Int, Name)]
do {
inNextToken
lhs += (inCurrentPos, ident())
} while (inToken == COMMA)
val tp = typedOpt()
val rhs = if (tp.isEmpty || inToken == EQUALS) {
accept(EQUALS)
if (!tp.isEmpty && inToken == USCORE) {
inNextToken
EmptyTree
} else {
expr()
}
} else {
newmods = newmods | Flags.DEFERRED
EmptyTree
}
var originalUsed = false
for ((pos, name) <- lhs.toList) yield atPos(pos) {
if (inIDE && !originalUsed) {
originalUsed = true
ValDef(newmods, name, tp, rhs)
} else ValDef(newmods, name, tp.duplicate, rhs.duplicate)
}
}
*/
/** FunDef ::= FunSig `:' Type `=' Expr
* | FunSig [nl] `{' Block `}'
* | this ParamClause ParamClauses (`=' ConstrExpr | [nl] ConstrBlock)
* FunDcl ::= FunSig [`:' Type]
* FunSig ::= id [FunTypeParamClause] ParamClauses
*/
def funDefOrDcl(mods: Modifiers): Tree = {
var pos = inSkipToken // position of `def'
if (inToken == THIS) {
atPos(inCurrentPos) {
inNextToken
val vparamss = paramClauses(nme.CONSTRUCTOR, implicitClassViews map (_.duplicate), false)
newLineOptWhenFollowedBy(LBRACE)
val rhs = if (inToken == LBRACE) constrBlock(vparamss)
else { accept(EQUALS); constrExpr(vparamss) }
DefDef(mods, nme.CONSTRUCTOR, List(), vparamss, TypeTree(), rhs)
}
} else {
var newmods = mods
val namePos = inCurrentPos
val name = ident()
if (name != nme.ERROR) pos = namePos
atPos(pos) {
// implicitViewBuf is for view bounded type parameters of the form
// [T <% B]; it contains the equivalent implicit parameter, i.e. (implicit p: T => B)
val implicitViewBuf = new ListBuffer[Tree]
val tparams = typeParamClauseOpt(name, implicitViewBuf)
val vparamss = paramClauses(name, implicitViewBuf.toList, false)
newLineOptWhenFollowedBy(LBRACE)
var restype = typedOpt()
val rhs =
if (isStatSep || inToken == RBRACE) {
if (restype.isEmpty) restype = scalaUnitConstr
newmods = newmods | Flags.DEFERRED
EmptyTree
} else if (restype.isEmpty && inToken == LBRACE) {
restype = scalaUnitConstr
blockExpr()
} else equalsExpr()
DefDef(newmods, name, tparams, vparamss, restype, rhs)
}
}
}
/** ConstrExpr ::= SelfInvocation
* | ConstrBlock
*/
def constrExpr(vparamss: List[List[ValDef]]): Tree =
if (inToken == LBRACE) constrBlock(vparamss)
else Block(List(selfInvocation(vparamss)), Literal(()))
/** SelfInvocation ::= this ArgumentExprs {ArgumentExprs}
*/
def selfInvocation(vparamss: List[List[ValDef]]): Tree =
atPos(accept(THIS)) {
newLineOptWhenFollowedBy(LBRACE)
var t = Apply(Ident(nme.CONSTRUCTOR), argumentExprs())
while (inToken == LPAREN || inToken == LBRACE) {
t = Apply(t, argumentExprs())
newLineOptWhenFollowedBy(LBRACE)
}
if (implicitClassViews.isEmpty) t
else Apply(t, vparamss.last.map(vp => Ident(vp.name)))
}
/** ConstrBlock ::= `{' SelfInvocation {semi BlockStat} `}'
*/
def constrBlock(vparamss: List[List[ValDef]]): Tree =
atPos(inSkipToken) {
val statlist = new ListBuffer[Tree]
statlist += selfInvocation(vparamss)
val stats = if (isStatSep) { inNextToken; blockStatSeq(statlist) }
else statlist.toList
accept(RBRACE)
Block(stats, Literal(()))
}
/** TypeDef ::= Id [TypeParamClause] `=' Type
* TypeDcl ::= Id [TypeParamClause] TypeBounds
*/
def typeDefOrDcl(mods: Modifiers): Tree =
atPos(inCurrentPos) {
val name = ident().toTypeName
// @M! a type alias as well as an abstract type may declare type parameters
val tparams = inToken match {
case LBRACKET =>
typeParamClauseOpt(name, null)
case _ =>
Nil
}
inToken match {
case EQUALS =>
inNextToken
TypeDef(mods, name, tparams, typ())
case SUPERTYPE | SUBTYPE | SEMI | NEWLINE | NEWLINES | COMMA | RBRACE =>
TypeDef(mods | Flags.DEFERRED, name, tparams, typeBounds())
case _ =>
syntaxErrorOrIncomplete("`=', `>:', or `<:' expected", true)
EmptyTree
}
}
/** Hook for IDE, for top-level classes/objects */
def topLevelTmplDef: Tree = {
val annots = annotations(true)
val mods = modifiers() withAnnotations annots
tmplDef(mods)
}
/** TmplDef ::= [case] class ClassDef
* | [case] object ObjectDef
* | [override] trait TraitDef
*/
def tmplDef(mods: Modifiers): Tree = {
if (mods.hasFlag(Flags.LAZY)) syntaxError("classes cannot be lazy", false)
inToken match {
case TRAIT =>
classDef(mods | Flags.TRAIT | Flags.ABSTRACT)
case CLASS =>
classDef(mods)
case CASECLASS =>
classDef(mods | Flags.CASE)
case OBJECT =>
objectDef(mods)
case CASEOBJECT =>
objectDef(mods | Flags.CASE)
case _ =>
syntaxErrorOrIncomplete("expected start of definition", true)
EmptyTree
}
}
/** ClassDef ::= Id [TypeParamClause] {Annotation}
[AccessModifier] ClassParamClauses RequiresTypeOpt ClassTemplateOpt
* TraitDef ::= Id [TypeParamClause] RequiresTypeOpt TraitTemplateOpt
*/
def classDef(mods: Modifiers): ClassDef = {
var pos = inSkipToken
var namePos = inCurrentPos
val name = ident().toTypeName
if (name != nme.ERROR) pos = namePos
atPos(pos) {
val savedViews = implicitClassViews
val implicitViewBuf = new ListBuffer[Tree]
val tparams = typeParamClauseOpt(name, implicitViewBuf)
implicitClassViews = implicitViewBuf.toList
if (!implicitClassViews.isEmpty && mods.hasFlag(Flags.TRAIT)) {
syntaxError("traits cannot have type parameters with <% bounds", false)
implicitClassViews = List()
}
val constrAnnots = annotations(false)
val (constrMods, vparamss) =
if (mods.hasFlag(Flags.TRAIT)) (Modifiers(Flags.TRAIT), List())
else (accessModifierOpt(), paramClauses(name, implicitClassViews, mods.hasFlag(Flags.CASE)))
val thistpe = requiresTypeOpt()
var mods1 =
if (mods hasFlag Flags.TRAIT)
if (inToken == SUBTYPE) mods | Flags.DEFERRED
else mods
else if (inToken == SUBTYPE) {
syntaxError("classes are not allowed to be virtual", false)
mods
}
else
mods
var template = templateOpt(mods1, name, constrMods withAnnotations constrAnnots, vparamss)
if (!thistpe.isEmpty) {
if (template.self.isEmpty) {
template = copy.Template(
template, template.parents, makeSelfDef(nme.WILDCARD, thistpe), template.body)
} else syntaxError("`requires' cannot be combined with explicit self type", false)
}
if (isInterface(mods1, template.body)) mods1 |= Flags.INTERFACE
val result = ClassDef(mods1, name, tparams, template)
implicitClassViews = savedViews
result
}
}
/** ObjectDef ::= Id ClassTemplateOpt
*/
def objectDef(mods: Modifiers): ModuleDef = {
var pos = inSkipToken
var namePos = inCurrentPos
val name = ident().toTermName
if (name != nme.ERROR) pos = namePos
atPos(pos) {
val mods1 = if (inToken == SUBTYPE) mods | Flags.DEFERRED else mods
val template = templateOpt(mods1, name, NoMods, List())
ModuleDef(mods1, name, template)
}
}
/** ClassParents ::= AnnotType {`(' [Exprs [`,']] `)'} {with AnnotType}
* TraitParents ::= AnnotType {with AnnotType}
*/
def templateParents(isTrait: Boolean): (List[Tree], List[List[Tree]]) = {
val parents = new ListBuffer[Tree] + annotType(false)
val argss = new ListBuffer[List[Tree]]
if (inToken == LPAREN && !isTrait)
do { argss += argumentExprs() } while (inToken == LPAREN)
else argss += List()
while (inToken == WITH) {
inNextToken
parents += annotType(false)
}
(parents.toList, argss.toList)
}
/** ClassTemplate ::= [EarlyDefs with] ClassParents [TemplateBody]
* TraitTemplate ::= [EarlyDefs with] TraitParents [TemplateBody]
* EarlyDefs ::= `{' [EarlyDef {semi EarlyDef}] `}'
* EarlyDef ::= Annotations Modifiers PatDef
*/
def template(isTrait: Boolean): (List[Tree], List[List[Tree]], ValDef, List[Tree]) = {
newLineOptWhenFollowedBy(LBRACE)
if (inToken == LBRACE) {
// @S: pre template body cannot stub like post body can!
val (self, body) = templateBody(true)
if (inToken == WITH && self.isEmpty) {
val earlyDefs: List[Tree] = body flatMap {
case vdef @ ValDef(mods, name, tpt, rhs) if !(mods hasFlag Flags.DEFERRED) =>
List(copy.ValDef(vdef, mods | Flags.PRESUPER, name, tpt, rhs))
case tdef @ TypeDef(mods, name, tparams, rhs) =>
List(copy.TypeDef(tdef, mods | Flags.PRESUPER, name, tparams, rhs))
case stat if !stat.isEmpty =>
syntaxError(stat.pos, "only type definitions and concrete field definitions allowed in early object initialization section", false)
List()
case _ => List()
}
inNextToken
val (parents, argss) = templateParents(isTrait)
val (self1, body1) = templateBodyOpt(isTrait)
(parents, argss, self1, earlyDefs ::: body1)
} else {
(List(), List(List()), self, body)
}
} else {
val (parents, argss) = templateParents(isTrait)
val (self, body) = templateBodyOpt(isTrait)
(parents, argss, self, body)
}
}
def isInterface(mods: Modifiers, body: List[Tree]): Boolean =
(mods hasFlag Flags.TRAIT) && (body forall treeInfo.isInterfaceMember)
/** ClassTemplateOpt ::= 'extends' ClassTemplate | [['extends'] TemplateBody]
* TraitTemplateOpt ::= TraitExtends TraitTemplate | [['extends'] TemplateBody] | '<:' TemplateBody
* TraitExtends ::= 'extends' | `<:'
*/
def templateOpt(mods: Modifiers, name: Name, constrMods: Modifiers,
vparamss: List[List[ValDef]]): Template = {
val pos = inCurrentPos;
val (parents0, argss, self, body) =
if (inToken == EXTENDS || settings.Xexperimental.value && (mods hasFlag Flags.TRAIT) && inToken == SUBTYPE) {
inNextToken
template(mods hasFlag Flags.TRAIT)
} else if ((inToken == SUBTYPE) && (mods hasFlag Flags.TRAIT)) {
inNextToken
template(true)
} else {
newLineOptWhenFollowedBy(LBRACE)
val (self, body) = templateBodyOpt(false)
(List(), List(List()), self, body)
}
var parents = parents0
if (name != nme.ScalaObject.toTypeName && !isInterface(mods, body))
parents = parents ::: List(scalaScalaObjectConstr)
if (parents.isEmpty)
parents = List(scalaAnyRefConstr)
if (mods.hasFlag(Flags.CASE)) parents = parents ::: List(productConstr)
val tree = Template(parents, self, constrMods, vparamss, argss, body)
// @S: if nothing parsed, don't use next position!
// @S: if primary constructor does not always have the same position, then the IDE gets confused.
// @S: since build compiler is used to generate IDE files, don't set position here!
tree
// if (pos == inCurrentPos || inIDE) tree else atPos(pos) {tree}
}
/* -------- TEMPLATES ------------------------------------------- */
/** TemplateBody ::= [nl] `{' TemplateStatSeq `}'
* @param isPre specifies whether in early initializer (true) or not (false)
*/
def templateBody(isPre: Boolean) = {
accept(LBRACE)
val result @ (self, stats) = templateStatSeq(isPre)
accept(RBRACE)
if (stats.isEmpty) (self, List(EmptyTree)) else result
}
def templateBodyOpt(traitParentSeen: Boolean): (ValDef, List[Tree]) = {
newLineOptWhenFollowedBy(LBRACE)
if (inToken == LBRACE) {
templateBody(false)
} else {
if (inToken == LPAREN)
syntaxError((if (traitParentSeen) "parents of traits" else "traits or objects")+
" may not have parameters", true)
(emptyValDef, List())
}
}
/** Refinement ::= [nl] `{' RefineStat {semi RefineStat} `}'
*/
def refinement(): List[Tree] = {
accept(LBRACE)
val body = refineStatSeq()
accept(RBRACE)
body
}
/* -------- STATSEQS ------------------------------------------- */
/** Packaging ::= package QualId [nl] `{' TopStatSeq `}'
*/
def packaging(pkgPos: Int): Tree = {
val pkg = qualId()
val pos = if (pkg.pos != NoPosition) pkg.pos else i2p(pkgPos)
atPos(pos) {
newLineOptWhenFollowedBy(LBRACE)
accept(LBRACE)
val stats = topStatSeq()
accept(RBRACE)
makePackaging(pkg, stats)
}
}
/** TopStatSeq ::= TopStat {semi TopStat}
* TopStat ::= Annotations Modifiers TmplDef
* | Packaging
* | package object objectDef
* | Import
* |
*/
def topStatSeq(): List[Tree] = {
val stats = new ListBuffer[Tree]
while (inToken != RBRACE && inToken != EOF) {
if (inToken == PACKAGE) {
val pkgPos = accept(PACKAGE)
stats += {
if (inToken == OBJECT)
atPos(pkgPos) { makePackageObject(objectDef(NoMods)) }
else packaging(pkgPos)
}
} else if (inToken == IMPORT) {
stats ++= importClause()
// XXX: IDE hook this all.
} else if (inToken == CLASS ||
inToken == CASECLASS ||
inToken == TRAIT ||
inToken == OBJECT ||
inToken == CASEOBJECT ||
inToken == LBRACKET || //todo: remove
inToken == AT ||
isModifier) {
stats ++ joinComment(List(topLevelTmplDef))
} else if (!isStatSep) {
syntaxErrorOrIncomplete("expected class or object definition", true)
}
if (inToken != RBRACE && inToken != EOF) acceptStatSep()
}
stats.toList
}
/** TemplateStatSeq ::= [id [`:' Type] `=>'] TemplateStat {semi TemplateStat}
* TemplateStat ::= Import
* | Annotations Modifiers Def
* | Annotations Modifiers Dcl
* | Expr1
* | super ArgumentExprs {ArgumentExprs}
* |
* @param isPre specifies whether in early initializer (true) or not (false)
*/
def templateStatSeq(isPre : Boolean) = checkNoEscapingPlaceholders {
var self: ValDef = emptyValDef
val stats = new ListBuffer[Tree]
if (isExprIntro) {
val first = expr(InTemplate) // @S: first statement is potentially converted so cannot be stubbed.
if (inToken == ARROW) {
first match {
case Typed(tree @ This(name), tpt) if (name == nme.EMPTY.toTypeName) =>
self = makeSelfDef(nme.WILDCARD, tpt).setPos(tree.pos)
case _ =>
convertToParam(first) match {
case tree @ ValDef(_, name, tpt, EmptyTree) if (name != nme.ERROR) =>
self = makeSelfDef(name, tpt).setPos(tree.pos)
case _ =>
}
}
inNextToken
} else {
stats += first
if (in.token != RBRACE && in.token != EOF/* !isStatSep(in.token)*/) acceptStatSep()
}
}
while (inToken != RBRACE && inToken != EOF) {
if (inToken == IMPORT) {
stats ++= importClause()
} else if (isExprIntro) {
stats += statement(InTemplate)
} else if (isDefIntro || isModifier || inToken == LBRACKET /*todo: remove */ || inToken == AT) {
if (isPre) // @S: avoid caching by calling a different method that does the same thing (except in the IDE)
stats ++= joinComment(preNonLocalDefOrDcl)
else stats ++= joinComment(nonLocalDefOrDcl)
} else if (!isStatSep) {
syntaxErrorOrIncomplete("illegal start of definition", true)
}
if (inToken != RBRACE && inToken != EOF) acceptStatSep()
}
(self, stats.toList)
}
/** RefineStatSeq ::= RefineStat {semi RefineStat}
* RefineStat ::= Dcl
* | type TypeDef
* |
*/
def refineStatSeq(): List[Tree] = checkNoEscapingPlaceholders {
val stats = new ListBuffer[Tree]
while (inToken != RBRACE && inToken != EOF) {
if (isDclIntro) { // don't IDE hook
stats ++= joinComment(defOrDcl(NoMods))
} else if (!isStatSep) {
syntaxErrorOrIncomplete("illegal start of declaration", true)
}
if (inToken != RBRACE) acceptStatSep()
}
stats.toList
}
/** overridable IDE hook for local definitions of blockStatSeq
* Here's an idea how to fill in start and end positions.
def localDef : List[Tree] = {
atEndPos {
atStartPos(inCurrentPos) {
val annots = annotations(true)
val mods = localModifiers() withAnnotations annots
if (!(mods hasFlag ~(Flags.IMPLICIT | Flags.LAZY))) defOrDcl(mods)
else List(tmplDef(mods))
}
} (inCurrentPos)
}
*/
def localDef : List[Tree] = {
val annots = annotations(true)
val mods = localModifiers() withAnnotations annots
if (!(mods hasFlag ~(Flags.IMPLICIT | Flags.LAZY))) defOrDcl(mods)
else List(tmplDef(mods))
}
/** BlockStatSeq ::= { BlockStat semi } [ResultExpr]
* BlockStat ::= Import
* | Annotations [implicit] [lazy] Def
* | Annotations LocalModifiers TmplDef
* | Expr1
* |
*/
def blockStatSeq(stats: ListBuffer[Tree]): List[Tree] = checkNoEscapingPlaceholders {
var keepGoing = true
var hasError = false
while ((inToken != RBRACE) && (inToken != EOF) && (inToken != CASE) && keepGoing) {
var hasError0 = hasError
hasError = false
if (inToken == IMPORT) {
stats ++= importClause()
acceptStatSep()
} else if (isExprIntro) {
stats += statement(InBlock)
if (inToken != RBRACE && inToken != CASE) acceptStatSep()
} else if (isDefIntro || isLocalModifier || in.token == AT) {
stats ++= localDef
if (inToken == RBRACE || inToken == CASE) {
syntaxError("block must end in result expression, not in definition", false)
stats += Literal(()).setPos(inCurrentPos)
} else acceptStatSep()
} else if (isStatSep) {
inNextToken
} else {
syntaxErrorOrIncomplete("illegal start of statement", true)
if (hasError0) keepGoing = false else hasError = true
}
}
stats.toList
}
/** CompilationUnit ::= [package QualId semi] TopStatSeq
*/
def compilationUnit(): Tree = checkNoEscapingPlaceholders {
var pos = inCurrentPos;
{
val ts = new ListBuffer[Tree]
// @S: the IDE can insert phantom semi-colons before package during editing
// @S: just eat them (doesn't really change the grammar)
while (inToken == SEMI) inNextToken
if (inToken == PACKAGE) {
pos = inSkipToken
if (in.token == OBJECT) {
ts += makePackageObject(objectDef(NoMods))
if (inToken != EOF) {
acceptStatSep()
ts ++= topStatSeq()
}
} else {
val pkg = qualId()
newLineOptWhenFollowedBy(LBRACE)
if (inToken == EOF) {
ts += makePackaging(pkg, List())
} else if (isStatSep) {
inNextToken
ts += makePackaging(pkg, topStatSeq())
} else {
accept(LBRACE)
ts += makePackaging(pkg, topStatSeq())
accept(RBRACE)
ts ++= topStatSeq()
}
}
} else {
ts ++= topStatSeq()
}
val stats = ts.toList
val usePos =
if (stats.isEmpty || stats.head.pos == NoPosition) i2p(pos)
else stats.head.pos
atPos(usePos) { stats match {
case List(stat @ PackageDef(_, _)) => stat
case _ => makePackaging(Ident(nme.EMPTY_PACKAGE_NAME), stats)
}}
}
}
}
}