/* NSC -- new scala compiler
* Copyright 2005 LAMP/EPFL
* @author Martin Odersky
*/
// $Id$
//todo: rewrite or disallow new T where T is a trait (currently: <init> not a member of T)
package scala.tools.nsc.typechecker;
import nsc.util.ListBuffer;
import symtab.Flags._;
import scala.tools.nsc.util.Position;
import collection.mutable.HashMap;
/** Methods to create symbols and to enter them into scopes. */
[_trait_] abstract class Typers: Analyzer {
import global._;
import definitions._;
import posAssigner.atPos;
var appcnt = 0;
var idcnt = 0;
var selcnt = 0;
var implcnt = 0;
var impltime = 0l;
private val transformed = new HashMap[Tree, Tree];
private val superDefs = new HashMap[Symbol, ListBuffer[Tree]];
def resetTyper: unit = {
resetContexts;
transformed.clear;
superDefs.clear;
}
def newTyper(context: Context): Typer = new Typer(context);
class Typer(context0: Context) {
import context0.unit;
val infer = new Inferencer(context0) {
override def isCoercible(tp: Type, pt: Type): boolean =
tp.isError || pt.isError ||
context0.reportGeneralErrors && // this condition prevents chains of views
inferView(Position.NOPOS, tp, pt, false) != EmptyTree
}
private def inferView(pos: int, from: Type, to: Type, reportAmbiguous: boolean): Tree = {
if (settings.debug.value) log("infer view from " + from + " to " + to);//debug
if (phase.erasedTypes) EmptyTree
else inferImplicit(pos, functionType(List(from), to), true, reportAmbiguous);
}
private def inferView(pos: int, from: Type, name: Name, reportAmbiguous: boolean): Tree = {
val to = refinedType(List(WildcardType), NoSymbol);
val psym = (if (name.isTypeName) to.symbol.newAbstractType(pos, name)
else to.symbol.newValue(pos, name)) setInfo WildcardType;
to.decls.enter(psym);
inferView(pos, from, to, reportAmbiguous)
}
import infer._;
private var namerCache: Namer = null;
def namer = {
if (namerCache == null || namerCache.context != context) namerCache = new Namer(context);
namerCache
}
private var context = context0;
/** Mode constants
*/
val NOmode = 0x000;
val EXPRmode = 0x001; // these 3 modes are mutually exclusive.
val PATTERNmode = 0x002;
val TYPEmode = 0x004;
val INCONSTRmode = 0x008; // orthogonal to above. When set we are
// in the body of a constructor
val FUNmode = 0x10; // orthogonal to above. When set
// we are looking for a method or constructor
val POLYmode = 0x020; // orthogonal to above. When set
// expression types can be polymorphic.
val QUALmode = 0x040; // orthogonal to above. When set
// expressions may be packages and
// Java statics modules.
val TAPPmode = 0x080; // Set for the function/type constructor part
// of a type application. When set we do not
// decompose PolyTypes.
val SUPERCONSTRmode = 0x100; // Set for the `super' in a superclass constructor call
// super.<init>
private val stickyModes: int = EXPRmode | PATTERNmode | TYPEmode;
/** Report a type error.
* @param pos The position where to report the error
* @param ex The exception that caused the error */
def reportTypeError(pos: int, ex: TypeError): unit = {
val msg = ex match {
case CyclicReference(sym, info: TypeCompleter) =>
info.tree match {
case ValDef(_, _, tpt, _) if (tpt.tpe == null) =>
"recursive " + sym + " needs type"
case DefDef(_, _, _, _, tpt, _) if (tpt.tpe == null) =>
"recursive " + sym + " needs result type"
case _ =>
ex.getMessage()
}
case _ =>
ex.getMessage()
}
if (settings.debug.value) ex.printStackTrace();
if (context.reportGeneralErrors) error(pos, msg)
else throw new Error(msg)
}
/** Check that tree is a stable expression.
*/
def checkStable(tree: Tree): Tree =
if (treeInfo.isPureExpr(tree) || tree.tpe.isError) tree;
else errorTree(tree, "stable identifier required, but " + tree + " found.");
/** Check that type `tp' is not a subtype of itself.
*/
def checkNonCyclic(pos: int, tp: Type): unit = {
def checkNotLocked(sym: Symbol): boolean = {
sym.initialize;
if (sym hasFlag LOCKED) {
error(pos, "cyclic aliasing or subtyping involving " + sym); false
} else true
}
tp match {
case TypeRef(pre, sym, args) =>
if (checkNotLocked(sym) && (sym.isAliasType || sym.isAbstractType)) {
//System.out.println("checking " + sym);//DEBUG
checkNonCyclic(pos, pre.memberInfo(sym).subst(sym.typeParams, args), sym);
}
case SingleType(pre, sym) =>
checkNotLocked(sym)
case st: SubType =>
checkNonCyclic(pos, st.supertype)
case ct: CompoundType =>
for (val p <- ct.parents) checkNonCyclic(pos, p)
case _ =>
}
}
def checkNonCyclic(pos: int, tp: Type, lockedSym: Symbol): unit = {
lockedSym.setFlag(LOCKED);
checkNonCyclic(pos, tp);
lockedSym.resetFlag(LOCKED)
}
/** Check that type of given tree does not contain local or private components
*/
object checkNoEscaping extends TypeMap {
private var owner: Symbol = _;
private var scope: Scope = _;
private var badSymbol: Symbol = _;
/** Check that type `tree' does not refer to private components unless itself is wrapped
* in something private (`owner' tells where the type occurs). */
def privates[T <: Tree](owner: Symbol, tree: T): T = {
check(owner, EmptyScope, tree);
}
/** Check that type `tree' does not refer to entities defined in scope `scope'. */
def locals[T <: Tree](scope: Scope, pt: Type, tree: T): T =
if (isFullyDefined(pt)) tree setType pt else check(NoSymbol, scope, tree);
def check[T <: Tree](owner: Symbol, scope: Scope, tree: T): T = {
this.owner = owner;
this.scope = scope;
badSymbol = NoSymbol;
assert(tree.tpe != null, tree);//debug
apply(tree.tpe);
if (badSymbol == NoSymbol) tree
else {
error(tree.pos,
(if (badSymbol.hasFlag(PRIVATE)) "private " else "") + badSymbol +
" escapes its defining scope as part of type " + tree.tpe);
setError(tree)
}
}
override def apply(t: Type): Type = {
def checkNoEscape(sym: Symbol): unit = {
if (sym.hasFlag(PRIVATE)) {
var o = owner;
while (o != NoSymbol && o != sym.owner && !o.isLocal && !o.hasFlag(PRIVATE))
o = o.owner;
if (o == sym.owner) badSymbol = sym
} else if (sym.owner.isTerm) {
val e = scope.lookupEntry(sym.name);
if (e != null && e.sym == sym && e.owner == scope && !e.sym.isTypeParameterOrSkolem)
badSymbol = e.sym
}
}
if (badSymbol == NoSymbol)
t match {
case TypeRef(_, sym, _) => checkNoEscape(sym)
case SingleType(_, sym) => checkNoEscape(sym)
case _ =>
}
mapOver(t)
}
}
def reenterValueParams(vparamss: List[List[ValDef]]): unit =
for (val vparams <- vparamss; val vparam <- vparams) context.scope enter vparam.symbol;
def reenterTypeParams(tparams: List[AbsTypeDef]): List[Symbol] =
for (val tparam <- tparams) yield {
context.scope enter tparam.symbol;
tparam.symbol.deSkolemize
}
def attrInfo(attr: Tree): AttrInfo = attr match {
case Apply(Select(New(tpt), nme.CONSTRUCTOR), args) =>
Pair(tpt.tpe, args map {
case Literal(value) =>
value
case arg =>
error(arg.pos, "attribute argument needs to be a constant; found: " + arg);
null
})
}
/** Post-process an identifier or selection node, performing the following:
* (1) Check that non-function pattern expressions are stable
* (2) Check that packages and static modules are not used as values
* (3) Turn tree type into stable type if possible and required by context. */
private def stabilize(tree: Tree, pre: Type, mode: int, pt: Type): Tree = {
if (tree.symbol.hasFlag(OVERLOADED) && (mode & FUNmode) == 0)
inferExprAlternative(tree, pt);
val sym = tree.symbol;
if ((mode & (PATTERNmode | FUNmode)) == PATTERNmode && tree.isTerm) { // (1)
checkStable(tree)
} else if ((mode & (EXPRmode | QUALmode)) == EXPRmode && !sym.isValue) { // (2)
errorTree(tree, sym.toString() + " is not a value");
} else if (sym.isStable && pre.isStable && tree.tpe.symbol != ByNameParamClass &&
(pt.isStable || (mode & QUALmode) != 0 && !sym.isConstant ||
sym.isModule && !sym.isMethod)) {
tree.setType(singleType(pre, sym))
} else tree
}
def stabilizeFun(tree: Tree, mode: int, pt: Type): Tree = {
val sym = tree.symbol;
val pre = tree match {
case Select(qual, _) => qual.tpe
case _ => NoPrefix
}
if (tree.tpe.isInstanceOf[MethodType] && pre.isStable &&
(pt.isStable || (mode & QUALmode) != 0 && !sym.isConstant || sym.isModule)) {
assert(sym.tpe.paramTypes.isEmpty);
tree.setType(MethodType(List(), singleType(pre, sym)))
} else tree
}
/** Perform the following adaptations of expression, pattern or type `tree' wrt to
* given mode `mode' and given prototype `pt':
* (0) Convert expressions with constant types to literals
* (1) Resolve overloading, unless mode contains FUNmode
* (2) Apply parameterless functions
* (3) Apply polymorphic types to fresh instances of their type parameters and
* store these instances in context.undetparams,
* unless followed by explicit type application.
* (4) Do the following to unapplied methods used as values:
* (4.1) If the method has only implicit parameters pass implicit arguments
* (4.2) otherwise, convert to function by eta-expansion,
* except if the method is a constructor, in which case we issue an error.
* (5) Convert a class type that serves as a constructor in a pattern as follows:
* (5.1) If this type refers to a case class, set tree's type to the unique
* instance of its primary constructor that is a subtype of the expected type.
* (5.2) Otherwise, if this type is a subtype of scala.Seq[A], set trees' type
* to a method type from a repeated parameter sequence type A* to the expected type.
* (6) Convert all other types to TypeTree nodes.
* (7) When in TYPEmode nut not FUNmode, check that types are fully parameterized
* (8) When in both EXPRmode and FUNmode, add apply method calls to values of object type.
* (9) If there are undetermined type variables and not POLYmode, infer expression instance
* Then, if tree's type is not a subtype of expected type, try the following adaptations:
* (10) If the expected type is byte, short or char, and the expression
* is an integer fitting in the range of that type, convert it to that type.
* (11) Widen numeric literals to their expected type, if necessary
* (12) When in mode EXPRmode, convert E to { E; () } if expected type is Scala.unit.
* (13) When in mode EXPRmode, apply a view
* If all this fails, error
*/
// def adapt(tree: Tree, mode: int, pt: Type): Tree = {
protected def adapt(tree: Tree, mode: int, pt: Type): Tree = tree.tpe match {
case ct @ ConstantType(value) if ((mode & TYPEmode) == 0 && (ct <:< pt)) => // (0)
copy.Literal(tree, value)
case OverloadedType(pre, alts) if ((mode & FUNmode) == 0) => // (1)
inferExprAlternative(tree, pt);
adapt(tree, mode, pt)
case PolyType(List(), restpe) => // (2)
adapt(tree setType restpe, mode, pt);
case TypeRef(_, sym, List(arg))
if ((mode & EXPRmode) != 0 && sym == ByNameParamClass) => // (2)
adapt(tree setType arg, mode, pt);
case PolyType(tparams, restpe) if ((mode & TAPPmode) == 0) => // (3)
val tparams1 = cloneSymbols(tparams);
val tree1 = if (tree.isType) tree
else TypeApply(tree, tparams1 map (tparam =>
TypeTree() setPos tree.pos setType tparam.tpe)) setPos tree.pos;
context.undetparams = context.undetparams ::: tparams1;
adapt(tree1 setType restpe.substSym(tparams, tparams1), mode, pt)
case mt: ImplicitMethodType if ((mode & (EXPRmode | FUNmode)) == EXPRmode) => // (4.1)
val tree1 =
if (!context.undetparams.isEmpty & (mode & POLYmode) == 0) { // (9)
val tparams = context.undetparams;
context.undetparams = List();
inferExprInstance(tree, tparams, pt);
adapt(tree, mode, pt)
} else tree;
typed(applyImplicitArgs(tree1), mode, pt)
case mt: MethodType if ((mode & (EXPRmode | FUNmode)) == EXPRmode &&
isCompatible(tree.tpe, pt)) => // (4.2)
if (tree.symbol.isConstructor) errorTree(tree, "missing arguments for " + tree.symbol)
else {
typed(etaExpand(tree), mode, pt)
}
case _ =>
if (tree.isType) {
val clazz = tree.tpe.symbol;
if ((mode & PATTERNmode) != 0) { // (5)
if (tree.tpe.isInstanceOf[MethodType]) {
tree // everything done already
} else {
clazz.initialize;
if (clazz.hasFlag(CASE)) { // (5.1)
val tree1 = TypeTree() setPos tree.pos
setType
clazz.primaryConstructor.tpe.asSeenFrom(tree.tpe.prefix, clazz.owner);
// tree.tpe.prefix.memberType(clazz.primaryConstructor); //!!!
inferConstructorInstance(tree1, clazz.unsafeTypeParams, pt);
tree1
} else if (clazz.isSubClass(SeqClass)) { // (5.2)
pt.baseType(clazz).baseType(SeqClass) match {
case TypeRef(pre, seqClass, args) =>
tree.setType(MethodType(List(typeRef(pre, RepeatedParamClass, args)), pt))
case NoType =>
errorTree(tree, "expected pattern type " + pt +
" does not conform to sequence " + clazz)
}
} else {
if (!tree.tpe.isError)
error(tree.pos, clazz.toString() + " is neither a case class nor a sequence class");
setError(tree)
}
}
} else if ((mode & FUNmode) != 0) {
tree
} else if (tree.hasSymbol && !tree.symbol.unsafeTypeParams.isEmpty) { // (7)
errorTree(tree, "" + clazz + " takes type parameters");
} else tree match { // (6)
case TypeTree() => tree
case _ => TypeTree() setPos tree.pos setType tree.tpe
}
} else if ((mode & (EXPRmode | FUNmode)) == (EXPRmode | FUNmode) &&
((mode & TAPPmode) == 0 || tree.tpe.typeParams.isEmpty) &&
tree.tpe.member(nme.apply).filter(m => m.tpe.paramSectionCount > 0) != NoSymbol) { // (8)
typed(Select(tree, nme.apply) setPos tree.pos, mode, pt)
} else if (!context.undetparams.isEmpty & (mode & POLYmode) == 0) { // (9)
val tparams = context.undetparams;
context.undetparams = List();
inferExprInstance(tree, tparams, pt);
adapt(tree, mode, pt)
} else if (tree.tpe <:< pt) {
tree
} else {
val tree1 = constfold(tree, pt); // (10) (11)
if (tree1.tpe <:< pt) adapt(tree1, mode, pt)
else {
if ((mode & (EXPRmode | FUNmode)) == EXPRmode) {
pt match {
case TypeRef(_, sym, _) =>
// note: was if (pt.symbol == UnitClass) but this leads to a potentially
// infinite expansion if pt is constant type ()
if (sym == UnitClass && tree.tpe <:< AnyClass.tpe) // (12)
return typed(atPos(tree.pos)(Block(List(tree), Literal(()))), mode, pt)
case _ =>
}
if (context.reportGeneralErrors && !tree.tpe.isError && !pt.isError) {
// (13); the condition prevents chains of views
if (settings.debug.value) log("inferring view from " + tree.tpe + " to " + pt);
val coercion = inferView(tree.pos, tree.tpe, pt, true);
if (coercion != EmptyTree) {
if (settings.debug.value) log("inferred view from " + tree.tpe + " to " + pt + " = " + coercion + ":" + coercion.tpe);
return typed(Apply(coercion, List(tree)) setPos tree.pos, mode, pt);
}
}
}
if (settings.debug.value) log("error tree = " + tree);
typeErrorTree(tree, tree.tpe, pt)
}
}
}
// System.out.println("adapt " + tree + ":" + tree.tpe + ", mode = " + mode + ", pt = " + pt);
// adapt(tree, mode, pt)
// }
private def completeSuperType(supertpt: Tree, tparams: List[Symbol], enclTparams: List[Symbol], vparamss: List[List[ValDef]], superargs: List[Tree]): Type = {
enclTparams foreach context.scope.enter;
namer.enterValueParams(context.owner, vparamss);
val newTree = New(supertpt) setType
PolyType(tparams, appliedType(supertpt.tpe, tparams map (.tpe)));
val tree = typed(atPos(supertpt.pos)(Apply(Select(newTree, nme.CONSTRUCTOR), superargs)));
if (settings.debug.value) log("superconstr " + tree + " co = " + context.owner);//debug
tree.tpe
}
def parentTypes(templ: Template): List[Tree] = try {
if (templ.parents.isEmpty) List()
else {
var supertpt = typedTypeConstructor(templ.parents.head);
var mixins = templ.parents.tail map typedType;
// If first parent is trait, make it first mixin and add its superclass as first parent
while (supertpt.tpe.symbol != null && supertpt.tpe.symbol.initialize.isTrait) {
mixins = typedType(supertpt) :: mixins;
supertpt = TypeTree(supertpt.tpe.parents.head) setPos supertpt.pos;
}
if (supertpt.hasSymbol) {
val tparams = supertpt.symbol.typeParams;
if (!tparams.isEmpty) {
val constr @ DefDef(_, _, _, vparamss, _, Apply(_, superargs)) =
treeInfo.firstConstructor(templ.body);
val outercontext = context.outer;
supertpt = TypeTree(
newTyper(outercontext.makeNewScope(constr, outercontext.owner/*.newValue(templ.pos, newTermName("<dummy>"))*/))
.completeSuperType(
supertpt,
tparams,
context.owner.unsafeTypeParams,
vparamss map (.map(.duplicate.asInstanceOf[ValDef])),
superargs map (.duplicate))) setPos supertpt.pos;
}
}
//System.out.println("parents(" + context.owner + ") = " + supertpt :: mixins);//DEBUG
List.mapConserve(supertpt :: mixins)(tpt => checkNoEscaping.privates(context.owner, tpt))
}
} catch {
case ex: TypeError =>
reportTypeError(templ.pos, ex);
List(TypeTree(AnyRefClass.tpe))
}
/** Check that
* - all parents are class types,
* - first parent cluss is not a trait; following classes are traits,
* - final classes are not inherited,
* - sealed classes are only inherited by classes which are
* nested within definition of base class, or that occur within same
* statement sequence,
* - self-type of current class is a subtype of self-type of each parent class.
* - no two parents define same symbol.
*/
def validateParentClasses(parents: List[Tree], selfType: Type): unit = {
var c = context;
do { c = c.outer } while (c.owner == context.owner);
val defscope = c.scope;
def validateParentClass(parent: Tree, isFirst: boolean): unit =
if (!parent.tpe.isError) {
val psym = parent.tpe.symbol.initialize;
if (!psym.isClass)
error(parent.pos, "class type expected");
else if (!isFirst && !psym.isTrait)
error(parent.pos, "" + psym + " is not a trait; cannot be used as mixin");
else if (psym.hasFlag(FINAL))
error(parent.pos, "illegal inheritance from final class");
else if (psym.isSealed && !phase.erasedTypes) {
// are we in same scope as base type definition?
val e = defscope.lookupEntry(psym.name);
if (!(e != null && e.sym == psym && e.owner == defscope)) {
// we are not within same statement sequence
var c = context;
while (c != NoContext && c.owner != psym) c = c.outer.enclClass;
if (c == NoContext) error(parent.pos, "illegal inheritance from sealed " + psym)
}
}
if (!(selfType <:< parent.tpe.typeOfThis) && !phase.erasedTypes) {
System.out.println(context.owner);//debug
System.out.println(context.owner.thisSym);//debug
error(parent.pos, "illegal inheritance;\n self-type " +
selfType + " does not conform to " + parent +
"'s selftype " + parent.tpe.typeOfThis);
if (settings.explaintypes.value) explainTypes(selfType, parent.tpe.typeOfThis);
}
if (parents exists (p => p != parent && p.tpe.symbol == psym && !psym.isError))
error(parent.pos, "" + psym + " is inherited twice")
}
if (!parents.isEmpty) {
validateParentClass(parents.head, true);
for (val p <- parents.tail) validateParentClass(p, false);
}
}
def typedClassDef(cdef: ClassDef): Tree = {
val clazz = cdef.symbol;
reenterTypeParams(cdef.tparams);
val tparams1 = List.mapConserve(cdef.tparams)(typedAbsTypeDef);
val tpt1 = checkNoEscaping.privates(clazz.thisSym, typedType(cdef.tpt));
val impl1 = newTyper(context.make(cdef.impl, clazz, new Scope()))
.typedTemplate(cdef.impl, parentTypes(cdef.impl));
val impl2 = addSyntheticMethods(impl1, clazz);
copy.ClassDef(cdef, cdef.mods, cdef.name, tparams1, tpt1, impl2)
setType NoType
}
def typedModuleDef(mdef: ModuleDef): Tree = {
val clazz = mdef.symbol.moduleClass;
val impl1 = newTyper(context.make(mdef.impl, clazz, new Scope()))
.typedTemplate(mdef.impl, parentTypes(mdef.impl));
copy.ModuleDef(mdef, mdef.mods, mdef.name, impl1) setType NoType
}
def addGetterSetter(stat: Tree): List[Tree] = stat match {
case ValDef(mods, name, tpe, rhs) if (mods & LOCAL) == 0 && !stat.symbol.isModuleVar =>
val vdef = copy.ValDef(stat, mods | PRIVATE | LOCAL, nme.getterToLocal(name), tpe, rhs);
val value = vdef.symbol;
val getter = if ((mods & DEFERRED) != 0) value else value.getter(value.owner);
if (getter hasFlag OVERLOADED) System.out.println("overloaded getter: " + getter.alternatives + getter.alternatives.map(.tpe));//debug
assert(getter != NoSymbol, value);//debug
val getterDef: DefDef = {
val result = atPos(vdef.pos)(
DefDef(getter, vparamss =>
if ((mods & DEFERRED) != 0) EmptyTree
else typed(Select(This(value.owner), value), EXPRmode, value.tpe)));
checkNoEscaping.privates(getter, result.tpt);
result
}
def setterDef: DefDef = {
val setter = value.owner.info.decl(nme.getterToSetter(getter.name));
assert(setter != NoSymbol, getter);//debug
atPos(vdef.pos)(
DefDef(setter, vparamss =>
if ((mods & DEFERRED) != 0) EmptyTree
else typed(Assign(Select(This(value.owner), value),
Ident(vparamss.head.head)))))
}
val gs = if ((mods & MUTABLE) != 0) List(getterDef, setterDef)
else List(getterDef);
if ((mods & DEFERRED) != 0) gs else vdef :: gs
case DocDef(comment, defn) =>
addGetterSetter(defn) map (stat => DocDef(comment, stat))
case Attributed(attr, defn) =>
addGetterSetter(defn) map (stat => Attributed(attr.duplicate, stat))
case _ =>
List(stat)
}
def typedTemplate(templ: Template, parents1: List[Tree]): Template = {
val clazz = context.owner;
if (templ.symbol == NoSymbol) templ setSymbol clazz.newLocalDummy(templ.pos);
val selfType =
if (clazz.isAnonymousClass && !phase.erasedTypes)
intersectionType(clazz.info.parents, clazz.owner)
else clazz.typeOfThis;
// the following is necessary for templates generated later
new Namer(context.outer.make(templ, clazz, clazz.info.decls)).enterSyms(templ.body);
validateParentClasses(parents1, selfType);
val body1 = typedStats(templ.body flatMap addGetterSetter, templ.symbol);
copy.Template(templ, parents1, body1) setType clazz.tpe
}
def typedValDef(vdef: ValDef): ValDef = {
val sym = vdef.symbol;
var tpt1 = checkNoEscaping.privates(sym, typedType(vdef.tpt));
checkNonCyclic(vdef.pos, tpt1.tpe, sym);
val rhs1 =
if (vdef.rhs.isEmpty) {
if (sym.isVariable && sym.owner.isTerm && phase.id <= currentRun.typerPhase.id)
error(vdef.pos, "local variables must be initialized");
vdef.rhs
} else {
newTyper(context.make(vdef, sym)).transformedOrTyped(vdef.rhs, tpt1.tpe)
}
copy.ValDef(vdef, vdef.mods, vdef.name, tpt1, rhs1) setType NoType
}
/** Enter all aliases of local parameter accessors. */
def computeParamAliases(clazz: Symbol, vparamss: List[List[ValDef]], rhs: Tree): unit = {
if (settings.debug.value) log("computing param aliases for " + clazz + ":" + clazz.primaryConstructor.tpe + ":" + rhs);//debug
def decompose(call: Tree): Pair[Tree, List[Tree]] = call match {
case Apply(fn, args) =>
val Pair(superConstr, args1) = decompose(fn);
val formals = fn.tpe.paramTypes;
val args2 = if (formals.isEmpty || formals.last.symbol != RepeatedParamClass) args
else args.take(formals.length - 1) ::: List(EmptyTree);
if (args2.length != formals.length) assert(false, "mismatch " + clazz + " " + formals + " " + args2);//debug
Pair(superConstr, args1 ::: args2)
case Block(stats, expr) =>
decompose(stats.head)
case _ =>
Pair(call, List())
}
val Pair(superConstr, superArgs) = decompose(rhs);
assert(superConstr.symbol != null, superConstr);//debug
if (superConstr.symbol.isPrimaryConstructor) {
val superClazz = superConstr.symbol.owner;
if (!superClazz.hasFlag(JAVA)) {
val superParamAccessors = superClazz.constrParamAccessors;
if (superParamAccessors.length != superArgs.length) {
System.out.println("" + superClazz + ":" + superClazz.info.decls.toList.filter(.hasFlag(PARAMACCESSOR)));
assert(false, "mismatch: " + superParamAccessors + ";" + rhs + ";" + superClazz.info.decls); //debug
}
List.map2(superParamAccessors, superArgs) { (superAcc, superArg) =>
superArg match {
case Ident(name) =>
if (vparamss.exists(.exists(vp => vp.symbol == superArg.symbol))) {
var alias = superAcc.initialize.alias;
if (alias == NoSymbol)
alias = superAcc.getter(superAcc.owner);
if (alias != NoSymbol &&
superClazz.info.nonPrivateMember(alias.name) != alias)
alias = NoSymbol;
if (alias != NoSymbol) {
var ownAcc = clazz.info.decl(name);
if (ownAcc hasFlag ACCESSOR) ownAcc = ownAcc.accessed;
if (settings.debug.value) log("" + ownAcc + " has alias " + alias + alias.locationString);//debug
ownAcc.asInstanceOf[TermSymbol].setAlias(alias)
}
}
case _ =>
}
}
()
}
}
}
def typedDefDef(ddef: DefDef): DefDef = {
val meth = ddef.symbol;
reenterTypeParams(ddef.tparams);
reenterValueParams(ddef.vparamss);
val tparams1 = List.mapConserve(ddef.tparams)(typedAbsTypeDef);
val vparamss1 = List.mapConserve(ddef.vparamss)(vparams1 =>
List.mapConserve(vparams1)(typedValDef));
for (val vparams <- vparamss1; val vparam <- vparams) {
checkNoEscaping.locals(context.scope, WildcardType, vparam.tpt); ()
}
var tpt1 =
checkNoEscaping.locals(context.scope, WildcardType,
checkNoEscaping.privates(meth,
typedType(ddef.tpt)));
checkNonCyclic(ddef.pos, tpt1.tpe, meth);
val rhs1 =
if (ddef.name == nme.CONSTRUCTOR) {
if (!meth.hasFlag(SYNTHETIC) &&
!(meth.owner.isClass ||
meth.owner.isModuleClass ||
meth.owner.isAnonymousClass ||
meth.owner.isRefinementClass))
error(ddef.pos, "constructor definition not allowed here " + meth.owner);//debug
context.enclClass.owner.setFlag(INCONSTRUCTOR);
val result = typed(ddef.rhs, EXPRmode | INCONSTRmode, UnitClass.tpe);
context.enclClass.owner.resetFlag(INCONSTRUCTOR);
if (meth.isPrimaryConstructor && !phase.erasedTypes && reporter.errors() == 0)
computeParamAliases(meth.owner, vparamss1, result);
result
} else transformedOrTyped(ddef.rhs, tpt1.tpe);
copy.DefDef(ddef, ddef.mods, ddef.name, tparams1, vparamss1, tpt1, rhs1) setType NoType
}
def typedAbsTypeDef(tdef: AbsTypeDef): AbsTypeDef = {
val lo1 = checkNoEscaping.privates(tdef.symbol, typedType(tdef.lo));
val hi1 = checkNoEscaping.privates(tdef.symbol, typedType(tdef.hi));
checkNonCyclic(tdef.pos, tdef.symbol.tpe);
copy.AbsTypeDef(tdef, tdef.mods, tdef.name, lo1, hi1) setType NoType
}
def typedAliasTypeDef(tdef: AliasTypeDef): AliasTypeDef = {
reenterTypeParams(tdef.tparams);
val tparams1 = List.mapConserve(tdef.tparams)(typedAbsTypeDef);
val rhs1 = checkNoEscaping.privates(tdef.symbol, typedType(tdef.rhs));
checkNonCyclic(tdef.pos, tdef.symbol.tpe);
copy.AliasTypeDef(tdef, tdef.mods, tdef.name, tparams1, rhs1) setType NoType
}
private def enterLabelDef(stat: Tree): unit = stat match {
case ldef @ LabelDef(_, _, _) =>
if (ldef.symbol == NoSymbol)
ldef.symbol = namer.enterInScope(
context.owner.newLabel(ldef.pos, ldef.name) setInfo MethodType(List(), UnitClass.tpe));
case _ =>
}
def typedLabelDef(ldef: LabelDef): LabelDef = {
val restpe = ldef.symbol.tpe.resultType;
val rhs1 = typed(ldef.rhs, restpe);
ldef.params foreach (param => param.tpe = param.symbol.tpe);
copy.LabelDef(ldef, ldef.name, ldef.params, rhs1) setType restpe
}
def typedBlock(block: Block, mode: int, pt: Type): Block = {
namer.enterSyms(block.stats);
block.stats foreach enterLabelDef;
val stats1 =
if ((mode & INCONSTRmode) != 0) {
val constrCall = typed(block.stats.head, mode, WildcardType);
context.enclClass.owner.resetFlag(INCONSTRUCTOR);
constrCall :: typedStats(block.stats.tail, context.owner);
} else {
typedStats(block.stats, context.owner)
}
val expr1 = typed(block.expr, mode & ~(FUNmode | QUALmode), pt);
val block1 = copy.Block(block, stats1, expr1)
setType (if (treeInfo.isPureExpr(block)) expr1.tpe else expr1.tpe.deconst);
if (isFullyDefined(pt)) block1
else {
if (block1.tpe.symbol.isAnonymousClass)
block1 setType intersectionType(block1.tpe.parents, block1.tpe.symbol.owner);
checkNoEscaping.locals(context.scope, pt, block1)
}
}
def typedCase(cdef: CaseDef, pattpe: Type, pt: Type): CaseDef = {
val pat1: Tree = typedPattern(cdef.pat, pattpe);
val guard1: Tree = if (cdef.guard == EmptyTree) EmptyTree
else typed(cdef.guard, BooleanClass.tpe);
var body1: Tree = typed(cdef.body, pt);
if (!context.savedTypeBounds.isEmpty) {
context.restoreTypeBounds;
// the following is a hack to make the pattern matcher work
body1 =
typed {
atPos(body1.pos) {
TypeApply(Select(body1, Any_asInstanceOf), List(TypeTree(pt)))
}
}
}
copy.CaseDef(cdef, pat1, guard1, body1) setType body1.tpe
}
def typedCases(tree: Tree, cases: List[CaseDef], pattp: Type, pt: Type): List[CaseDef] = {
List.mapConserve(cases)(cdef =>
newTyper(context.makeNewScope(cdef, context.owner)).typedCase(cdef, pattp, pt))
}
def typedFunction(fun: Function, mode: int, pt: Type): Tree = {
def decompose(pt: Type): Triple[Symbol, List[Type], Type] =
if (isFunctionType(pt)
||
pt.symbol == PartialFunctionClass &&
fun.vparams.length == 1 && fun.body.isInstanceOf[Match])
Triple(pt.symbol, pt.typeArgs.init, pt.typeArgs.last)
else
Triple(FunctionClass(fun.vparams.length), fun.vparams map (x => NoType), WildcardType);
val Triple(clazz, argpts, respt) =
decompose(if (pt.symbol == TypedCodeClass) pt.typeArgs.head else pt);
val vparamSyms = List.map2(fun.vparams, argpts) { (vparam, argpt) =>
if (vparam.tpt.isEmpty)
vparam.tpt.tpe =
if (argpt == NoType) { error(vparam.pos, "missing parameter type"); ErrorType }
else argpt;
namer.enterSym(vparam);
vparam.symbol
}
val vparams = List.mapConserve(fun.vparams)(typedValDef);
for (val vparam <- vparams) {
checkNoEscaping.locals(context.scope, WildcardType, vparam.tpt); ()
}
val body = checkNoEscaping.locals(context.scope, respt, typed(fun.body, respt));
val formals = vparamSyms map (.tpe);
val restpe = body.tpe.deconst;
val funtpe = typeRef(clazz.tpe.prefix, clazz, formals ::: List(restpe));
val fun1 = copy.Function(fun, vparams, checkNoEscaping.locals(context.scope, restpe, body))
setType funtpe;
if (pt.symbol == TypedCodeClass) typed(atPos(fun.pos)(codify(fun1)))
else fun1
}
def typedRefinement(stats: List[Tree]): List[Tree] = {
namer.enterSyms(stats);
for (val stat <- stats) stat.symbol setFlag OVERRIDE;
typedStats(stats, NoSymbol);
}
def typedStats(stats: List[Tree], exprOwner: Symbol): List[Tree] =
List.mapConserve(stats) { stat =>
if (context.owner.isRefinementClass && !treeInfo.isDeclaration(stat))
errorTree(stat, "only declarations allowed here");
stat match {
case imp @ Import(_, _) =>
context = context.makeNewImport(imp);
stat.symbol.initialize;
EmptyTree
case _ =>
(if (exprOwner != context.owner && (!stat.isDef || stat.isInstanceOf[LabelDef]))
newTyper(context.make(stat, exprOwner)) else this).typed(stat)
}
}
protected def typed1(tree: Tree, mode: int, pt: Type): Tree = {
def funmode = mode & stickyModes | FUNmode | POLYmode;
def ptOrLub(tps: List[Type]) = if (isFullyDefined(pt)) pt else lub(tps);
def typedTypeApply(fun: Tree, args: List[Tree]): Tree = fun.tpe match {
case OverloadedType(pre, alts) =>
inferPolyAlternatives(fun, args.length);
typedTypeApply(fun, args)
case PolyType(tparams, restpe) if (tparams.length != 0) =>
if (tparams.length == args.length) {
val targs = args map (.tpe);
checkBounds(tree.pos, tparams, targs, "");
copy.TypeApply(tree, fun, args) setType restpe.subst(tparams, targs);
} else {
errorTree(tree, "wrong number of type parameters for " + treeSymTypeMsg(fun))
}
case ErrorType =>
setError(tree)
case _ =>
System.out.println(fun.toString() + " " + args);//debug
errorTree(tree, treeSymTypeMsg(fun) + " does not take type parameters.");
}
def typedApply(fun: Tree, args: List[Tree]): Tree = fun.tpe match {
case OverloadedType(pre, alts) =>
val args1 = List.mapConserve(args)(arg =>
typed(arg, mode & stickyModes, WildcardType));
inferMethodAlternative(fun, context.undetparams, args1 map (.tpe.deconst), pt);
typedApply(adapt(fun, funmode, WildcardType), args1);
case MethodType(formals0, restpe) =>
val formals = formalTypes(formals0, args.length);
if (formals.length != args.length) {
//System.out.println("" + formals.length + " " + args.length);//DEBUG
errorTree(tree, "wrong number of arguments for " + treeSymTypeMsg(fun))
} else {
val tparams = context.undetparams;
context.undetparams = List();
if (tparams.isEmpty) {
val args1 = List.map2(args, formals) ((arg, formal) =>
typed(arg, mode & stickyModes, formal));
def ifPatternSkipFormals(tp: Type) = tp match {
case MethodType(_, rtp) if ((mode & PATTERNmode) != 0) => rtp
case _ => tp
}
constfold(copy.Apply(tree, fun, args1).setType(ifPatternSkipFormals(restpe)));
} else {
assert((mode & PATTERNmode) == 0); // this case cannot arise for patterns
val lenientTargs = protoTypeArgs(tparams, formals, restpe, pt);
val strictTargs = List.map2(lenientTargs, tparams)((targ, tparam) =>
if (targ == WildcardType) tparam.tpe else targ);
def typedArg(tree: Tree, formal: Type): Tree = {
val lenientPt = formal.subst(tparams, lenientTargs);
val tree1 = typed(tree, mode & stickyModes | POLYmode, lenientPt);
val argtparams = context.undetparams;
context.undetparams = List();
if (!argtparams.isEmpty) {
val strictPt = formal.subst(tparams, strictTargs);
inferArgumentInstance(tree1, argtparams, strictPt, lenientPt);
}
tree1
}
val args1 = List.map2(args, formals)(typedArg);
if (args1 exists (.tpe.isError)) setError(tree)
else {
if (settings.debug.value) log("infer method inst " + fun + ", tparams = " + tparams + ", args = " + args1.map(.tpe) + ", pt = " + pt + ", lobounds = " + tparams.map(.tpe.bounds.lo));//debug
val undetparams = inferMethodInstance(fun, tparams, args1, pt);
val result = typedApply(fun, args1);
context.undetparams = undetparams;
result
}
}
}
case ErrorType =>
setError(tree)
case _ =>
errorTree(tree, "" + fun + " does not take parameters");
}
/** The qualifying class of a this or super with prefix `qual' */
def qualifyingClassContext(qual: Name): Context = {
if (qual == nme.EMPTY.toTypeName) {
if (context.enclClass.owner.isPackageClass)
error(tree.pos, "" + tree + " can be used only in a class, object, or template");
context.enclClass
} else {
var c = context.enclClass;
while (c != NoContext && c.owner.name != qual) c = c.outer.enclClass;
if (c == NoContext) error(tree.pos, "" + qual + " is not an enclosing class");
c
}
}
/** Attribute a selection where `tree' is `qual.name'.
* `qual' is already attributed.
*/
def typedSelect(qual: Tree, name: Name): Tree = {
val sym =
if (tree.symbol != NoSymbol) {
if (phase.erasedTypes && qual.isInstanceOf[Super]) qual.tpe = tree.symbol.owner.tpe;
if (false && settings.debug.value) { // todo: replace by settings.check.value?
val alts = qual.tpe.member(tree.symbol.name).alternatives;
if (!(alts exists (alt =>
alt == tree.symbol || alt.isTerm && (alt.tpe matches tree.symbol.tpe))))
assert(false, "symbol " + tree.symbol + tree.symbol.locationString + " not in " + alts + " of " + qual.tpe +
"\n members = " + qual.tpe.members +
"\n type history = " + qual.tpe.symbol.infosString +
"\n phase = " + phase);
}
tree.symbol
} else {
qual.tpe.member(name)
}
if (sym == NoSymbol && qual.isTerm && (qual.symbol == null || qual.symbol.isValue) &&
!phase.erasedTypes && !qual.tpe.widen.isError) {
val coercion = inferView(qual.pos, qual.tpe, name, true);
if (coercion != EmptyTree)
return typed(
copy.Select(tree, Apply(coercion, List(qual)) setPos qual.pos, name), mode, pt)
}
if (sym.info == NoType) {
if (settings.debug.value) log("qual = " + qual + ":" + qual.tpe + "\nSymbol=" + qual.tpe.symbol + "\nsymbol-info = " + qual.tpe.symbol.info + "\nscope-id = " + qual.tpe.symbol.info.decls.hashCode() + "\nmembers = " + qual.tpe.members + "\nfound = " + sym);
if (!qual.tpe.widen.isError)
error(tree.pos,
decode(name) + " is not a member of " + qual.tpe.widen +
(if (Position.line(tree.pos) > Position.line(qual.pos))
"\npossible cause: maybe a semicolon is missing before `" + name + "'?" else ""));
setError(tree)
} else {
val tree1 = tree match {
case Select(_, _) => copy.Select(tree, qual, name)
case SelectFromTypeTree(_, _) => copy.SelectFromTypeTree(tree, qual, name);
}
stabilize(checkAccessible(tree1, sym, qual.tpe, qual), qual.tpe, mode, pt);
}
}
/** Attribute an identifier consisting of a simple name or an outer reference.
* @param tree The tree representing the identifier.
* @param name The name of the identifier.
* Transformations: (1) Prefix class members with this.
* (2) Change imported symbols to selections
*/
def typedIdent(name: Name): Tree = {
def ambiguousError(msg: String) =
error(tree.pos, "reference to " + name + " is ambiguous;\n" + msg);
var defSym: Symbol = tree.symbol; // the directly found symbol
var pre: Type = NoPrefix; // the prefix type of defSym, if a class member
var qual: Tree = EmptyTree; // the qualififier tree if transformed tree is a select
if (defSym == NoSymbol) {
var defEntry: ScopeEntry = null; // the scope entry of defSym, if defined in a local scope
var cx = context;
while (defSym == NoSymbol && cx != NoContext) {
pre = cx.enclClass.thisSkolemType;
defEntry = cx.scope.lookupEntry(name);
if (defEntry != null) {
defSym = defEntry.sym;
} else {
cx = cx.enclClass;
defSym = pre.member(name) filter (sym => context.isAccessible(sym, pre, false));
if (defSym == NoSymbol) cx = cx.outer;
}
}
val symDepth = if (defEntry == null) cx.depth
else cx.depth - (cx.scope.nestingLevel - defEntry.owner.nestingLevel);
var impSym: Symbol = NoSymbol; // the imported symbol
var imports = context.imports; // impSym != NoSymbol => it is imported from imports.head
while (impSym == NoSymbol && !imports.isEmpty && imports.head.depth > symDepth) {
impSym = imports.head.importedSymbol(name);
if (impSym == NoSymbol) imports = imports.tail;
}
// detect ambiguous definition/import,
// update `defSym' to be the final resolved symbol,
// update `pre' to be `sym's prefix type in case it is an imported member,
// and compute value of:
// imported symbols take precedence over external package-owned symbols (hack?)
if (defSym.tpe != NoType && impSym.tpe != NoType && defSym.isExternal && defSym.owner.isPackageClass)
defSym = NoSymbol;
if (defSym.tpe != NoType) {
if (impSym.tpe != NoType)
ambiguousError(
"it is both defined in " + defSym.owner +
" and imported subsequently by \n" + imports.head);
else if (!defSym.owner.isClass || defSym.owner.isPackageClass || defSym.isTypeParameterOrSkolem)
pre = NoPrefix
else
qual = atPos(tree.pos)(gen.mkQualifier(pre));
} else {
if (impSym.tpe != NoType) {
var impSym1 = NoSymbol;
var imports1 = imports.tail;
def ambiguousImportError = ambiguousError(
"it is imported twice in the same scope by\n" + imports.head + "\nand " + imports1.head);
while (!imports1.isEmpty && imports1.head.depth == imports.head.depth) {
var impSym1 = imports1.head.importedSymbol(name);
if (impSym1 != NoSymbol) {
if (imports1.head.isExplicitImport(name)) {
if (imports.head.isExplicitImport(name)) ambiguousImportError;
impSym = impSym1;
imports = imports1;
} else if (!imports.head.isExplicitImport(name)) ambiguousImportError
}
imports1 = imports1.tail;
}
defSym = impSym;
qual = imports.head.qual;
pre = qual.tpe;
} else {
if (settings.debug.value) {
log(context.imports);//debug
}
error(tree.pos, "not found: " + decode(name));
defSym = context.owner.newErrorSymbol(name);
}
}
}
if (defSym.owner.isPackageClass) pre = defSym.owner.thisType;
val tree1 = if (qual == EmptyTree) tree
else atPos(tree.pos)(Select(qual, name));
// atPos necessary because qualifier might come from startContext
//System.out.println("check acc: " + defSym + " " + pre);//DEBUG
stabilize(checkAccessible(tree1, defSym, pre, qual), pre, mode, pt)
}
// begin typed1
val sym: Symbol = tree.symbol;
if (sym != null) sym.initialize;
//if (settings.debug.value && tree.isDef) log("typing definition of " + sym);//DEBUG
tree match {
case PackageDef(name, stats) =>
val stats1 = newTyper(context.make(tree, sym.moduleClass, sym.info.decls))
.typedStats(stats, NoSymbol);
copy.PackageDef(tree, name, stats1) setType NoType
case cdef @ ClassDef(_, _, _, _, _) =>
newTyper(context.makeNewScope(tree, sym)).typedClassDef(cdef)
case mdef @ ModuleDef(_, _, _) =>
newTyper(context.make(tree, sym.moduleClass)).typedModuleDef(mdef)
case vdef @ ValDef(_, _, _, _) =>
typedValDef(vdef)
case ddef @ DefDef(_, _, _, _, _, _) =>
newTyper(context.makeNewScope(tree, sym)).typedDefDef(ddef)
case tdef @ AbsTypeDef(_, _, _, _) =>
newTyper(context.makeNewScope(tree, sym)).typedAbsTypeDef(tdef)
case tdef @ AliasTypeDef(_, _, _, _) =>
newTyper(context.makeNewScope(tree, sym)).typedAliasTypeDef(tdef)
case ldef @ LabelDef(_, _, _) =>
var lsym = ldef.symbol;
var typer1 = this;
if (lsym == NoSymbol) { // labeldef is part of template
typer1 = newTyper(context.makeNewScope(tree, context.owner));
typer1.enterLabelDef(ldef);
}
typer1.typedLabelDef(ldef)
case Attributed(attr, defn) =>
val attr1 = typed(attr, AttributeClass.tpe);
val defn1 = typed(defn, mode, pt);
val ai = attrInfo(attr1);
if (ai != null) defn1.symbol.attributes = defn1.symbol.attributes ::: List(ai);
defn1
case DocDef(comment, defn) =>
typed(defn, mode, pt);
case block @ Block(_, _) =>
newTyper(context.makeNewScope(tree, context.owner))
.typedBlock(block, mode, pt)
case Sequence(elems) =>
val elems1 = List.mapConserve(elems)(elem => typed(elem, mode, pt));
copy.Sequence(tree, elems1) setType pt
case Alternative(alts) =>
val alts1 = List.mapConserve(alts)(alt => typed(alt, mode, pt));
copy.Alternative(tree, alts1) setType pt
case Star(elem) =>
val elem1 = typed(elem, mode, pt);
copy.Star(tree, elem1) setType pt
case Bind(name, body) =>
var vble = tree.symbol;
if (vble == NoSymbol) vble = context.owner.newValue(tree.pos, name);
if (vble.name != nme.WILDCARD) namer.enterInScope(vble);
val body1 = typed(body, mode, pt);
vble.setInfo(if (treeInfo.isSequenceValued(body)) seqType(body1.tpe) else body1.tpe);
copy.Bind(tree, name, body1) setSymbol vble setType body1.tpe; // buraq, was: pt
case ArrayValue(elemtpt, elems) =>
val elemtpt1 = typedType(elemtpt);
val elems1 = List.mapConserve(elems)(elem => typed(elem, mode, elemtpt1.tpe));
copy.ArrayValue(tree, elemtpt1, elems1)
setType (if (isFullyDefined(pt) && !phase.erasedTypes) pt
else appliedType(ArrayClass.typeConstructor, List(elemtpt1.tpe)))
case fun @ Function(_, _) =>
/*
newTyper(context.makeNewScope(tree, context.owner)).typedFunction(fun, mode, pt)
*/
tree.symbol = context.owner.newValue(tree.pos, nme.ANON_FUN_NAME) setFlag SYNTHETIC;
newTyper(context.makeNewScope(tree, tree.symbol)).typedFunction(fun, mode, pt)
case Assign(lhs, rhs) =>
def isGetter(sym: Symbol) = sym.info match {
case PolyType(List(), _) => sym.owner.isClass && !sym.isStable
case _ => false
}
val lhs1 = typed(lhs);
val varsym = lhs1.symbol;
if (varsym != null && isGetter(varsym)) {
lhs1 match {
case Select(qual, name) =>
typed(
Apply(
Select(qual, nme.getterToSetter(name)) setPos lhs.pos,
List(rhs)) setPos tree.pos, mode, pt)
}
} else if (varsym != null && (varsym.isVariable || varsym.isValue && phase.erasedTypes)) {
val rhs1 = typed(rhs, lhs1.tpe);
copy.Assign(tree, lhs1, rhs1) setType UnitClass.tpe;
} else {
System.out.println("" + lhs1 + " " + varsym + " " + varsym.isValue + " " + flagsToString(varsym.flags));//debug
if (!lhs1.tpe.isError) error(tree.pos, "assignment to non-variable ");
setError(tree)
}
case If(cond, thenp, elsep) =>
val cond1 = typed(cond, BooleanClass.tpe);
if (elsep.isEmpty) {
val thenp1 = typed(thenp, UnitClass.tpe);
copy.If(tree, cond1, thenp1, elsep) setType UnitClass.tpe
} else {
val thenp1 = typed(thenp, pt);
val elsep1 = typed(elsep, pt);
copy.If(tree, cond1, thenp1, elsep1) setType ptOrLub(List(thenp1.tpe, elsep1.tpe));
}
case Match(selector, cases) =>
val selector1 = typed(selector);
val cases1 = typedCases(tree, cases, selector1.tpe.widen, pt);
copy.Match(tree, selector1, cases1) setType ptOrLub(cases1 map (.tpe))
case Return(expr) =>
val enclFun = if (tree.symbol != NoSymbol) tree.symbol else context.owner.enclMethod;
if (!enclFun.isMethod || enclFun.isConstructor)
errorTree(tree, "return outside method definition")
else if (!context.owner.isInitialized)
errorTree(tree, "method " + context.owner + " has return statement; needs result type")
else {
val expr1: Tree = typed(expr, enclFun.tpe.finalResultType);
copy.Return(tree, expr1) setSymbol enclFun setType AllClass.tpe;
}
case Try(block, catches, finalizer) =>
val block1 = typed(block, pt);
val catches1 = typedCases(tree, catches, ThrowableClass.tpe, pt);
val finalizer1 = if (finalizer.isEmpty) finalizer
else typed(finalizer, UnitClass.tpe);
copy.Try(tree, block1, catches1, finalizer1)
setType ptOrLub(block1.tpe :: (catches1 map (.tpe)))
case Throw(expr) =>
val expr1 = typed(expr, ThrowableClass.tpe);
copy.Throw(tree, expr1) setType AllClass.tpe
case New(tpt: Tree) =>
var tpt1 = typedTypeConstructor(tpt);
if (tpt1.hasSymbol && !tpt1.symbol.typeParams.isEmpty) {
context.undetparams = cloneSymbols(tpt1.symbol.unsafeTypeParams);
tpt1 = TypeTree()
setPos tpt1.pos
setType appliedType(tpt1.tpe, context.undetparams map (.tpe));
}
if (tpt1.tpe.symbol.isTrait) error(tree.pos, "traits cannot be instantiated");
copy.New(tree, tpt1).setType(tpt1.tpe)
case Typed(expr, tpt @ Ident(name)) if (name == nme.WILDCARD_STAR.toTypeName) =>
val expr1 = typed(expr, mode & stickyModes, seqType(pt));
expr1.tpe.baseType(SeqClass) match {
case TypeRef(_, _, List(elemtp)) =>
copy.Typed(tree, expr1, tpt setType elemtp) setType elemtp
case _ =>
setError(tree)
}
case Typed(expr, tpt) =>
val tpt1 = typedType(tpt);
val expr1 = typed(expr, mode & stickyModes, tpt1.tpe);
copy.Typed(tree, expr1, tpt1) setType tpt1.tpe
case TypeApply(fun, args) =>
val args1 = List.mapConserve(args)(typedType);
// do args first in order to maintain conext.undetparams on the function side.
typedTypeApply(typed(fun, funmode | TAPPmode, WildcardType), args1)
case Apply(fun, args) =>
val stableApplication = fun.symbol != null && fun.symbol.isMethod && fun.symbol.isStable;
if (stableApplication && (mode & PATTERNmode) != 0) {
// treat stable function applications f() as expressions.
typed1(tree, mode & ~PATTERNmode | EXPRmode, pt)
} else {
val funpt = if ((mode & PATTERNmode) != 0) pt else WildcardType;
var fun1 = typed(fun, funmode, funpt);
if (stableApplication) fun1 = stabilizeFun(fun1, mode, pt);
// if function is overloaded, filter all alternatives that match
// number of arguments and expected result type.
// if (settings.debug.value) log("trans app " + fun1 + ":" + fun1.symbol + ":" + fun1.tpe + " " + args);//DEBUG
if (fun1.hasSymbol && fun1.symbol.hasFlag(OVERLOADED)) {
val argtypes = args map (arg => AllClass.tpe);
val pre = fun1.symbol.tpe.prefix;
val sym = fun1.symbol filter (alt =>
isApplicable(context.undetparams, pre.memberType(alt), argtypes, pt));
if (sym != NoSymbol)
fun1 = adapt(fun1 setSymbol sym setType pre.memberType(sym), funmode, WildcardType)
}
if (util.Statistics.enabled) appcnt = appcnt + 1;
typedApply(fun1, args)
}
case Super(qual, mix) =>
val Pair(clazz, selftype) =
if (tree.symbol != NoSymbol) {
Pair(tree.symbol, tree.symbol.thisType)
} else {
val clazzContext = qualifyingClassContext(qual);
Pair(clazzContext.owner, clazzContext.thisSkolemType)
}
if (clazz == NoSymbol) setError(tree)
else {
val owntype =
if (mix == nme.EMPTY.toTypeName)
if ((mode & SUPERCONSTRmode) != 0) clazz.info.parents.head
else intersectionType(clazz.info.parents)
else {
val ps = clazz.info.parents dropWhile (p => p.symbol.name != mix);
if (ps.isEmpty) {
System.out.println(clazz.info.parents map (.symbol.name));//debug
error(tree.pos, "" + mix + " does not name a base class of " + clazz);
ErrorType
} else ps.head
}
tree setSymbol clazz setType SuperType(selftype, owntype)
}
case This(qual) =>
val Pair(clazz, selftype) =
if (tree.symbol != NoSymbol) {
Pair(tree.symbol, tree.symbol.thisType)
} else {
val clazzContext = qualifyingClassContext(qual);
Pair(clazzContext.owner, clazzContext.thisSkolemType)
}
if (clazz == NoSymbol) setError(tree)
else {
val owntype = if (pt.isStable || (mode & QUALmode) != 0) selftype
else selftype.singleDeref;
tree setSymbol clazz setType owntype
}
case Select(qual @ Super(_, _), nme.CONSTRUCTOR) =>
val qual1 = typed(qual, EXPRmode | QUALmode | POLYmode | SUPERCONSTRmode, WildcardType);
// the qualifier type of a supercall constructor is its first parent class
typedSelect(qual1, nme.CONSTRUCTOR);
case Select(qual, name) =>
if (util.Statistics.enabled) selcnt = selcnt + 1;
var qual1 = typedQualifier(qual);
if (name.isTypeName) qual1 = checkStable(qual1);
typedSelect(qual1, name);
case Ident(name) =>
idcnt = idcnt + 1;
if (name == nme.WILDCARD && (mode & (PATTERNmode | FUNmode)) == PATTERNmode)
tree setType pt
else
typedIdent(name)
// todo: try with case Literal(Constant(()))
case Literal(value) =>
tree setType (if (value.tag == UnitTag) UnitClass.tpe else ConstantType(value))
case SingletonTypeTree(ref) =>
val ref1 = checkStable(typed(ref, EXPRmode | QUALmode, AnyRefClass.tpe));
tree setType ref1.tpe.resultType;
case SelectFromTypeTree(qual, selector) =>
tree setType typedSelect(typedType(qual), selector).tpe
case CompoundTypeTree(templ: Template) =>
tree setType {
val parents1 = List.mapConserve(templ.parents)(typedType);
if (parents1 exists (.tpe.isError)) ErrorType
else {
val decls = new Scope();
val self = refinedType(parents1 map (.tpe), context.enclClass.owner, decls);
newTyper(context.make(templ, self.symbol, decls)).typedRefinement(templ.body);
self
}
}
case AppliedTypeTree(tpt, args) =>
val tpt1 = typed1(tpt, mode | FUNmode | TAPPmode, WildcardType);
val tparams = tpt1.symbol.typeParams;
val args1 = List.mapConserve(args)(typedType);
if (tpt1.tpe.isError) {
setError(tree)
} else if (tparams.length == args1.length) {
val argtypes = args1 map (.tpe);
val owntype = if (tpt1.symbol.isClass) appliedType(tpt1.tpe, argtypes)
else tpt1.tpe.subst(tparams, argtypes);
TypeTree() setPos tree.pos setType owntype
} else if (tparams.length == 0) {
errorTree(tree, "" + tpt1.tpe + " does not take type parameters")
} else {
System.out.println("" + tpt1 + ":" + tpt1.symbol + ":" + tpt1.symbol.info);//debug
errorTree(tree, "wrong number of type arguments for " + tpt1.tpe + ", should be " + tparams.length)
}
}
}
def typed(tree: Tree, mode: int, pt: Type): Tree =
try {
if (settings.debug.value) {
assert(pt != null, tree);//debug
//System.out.println("typing " + tree);//DEBUG
}
val tree1 = if (tree.tpe != null) tree else typed1(tree, mode, pt);
//System.out.println("typed " + tree1 + ":" + tree1.tpe);//debug
val result = if (tree1.isEmpty) tree1 else adapt(tree1, mode, pt);
//System.out.println("adapted " + tree1 + ":" + tree1.tpe + " to " + pt);//debug
result
} catch {
case ex: TypeError =>
reportTypeError(tree.pos, ex);
setError(tree)
case ex: Throwable =>
if (settings.debug.value)
System.out.println("exception when typing " + tree + ", pt = " + pt);
throw(ex)
}
def atOwner(owner: Symbol): Typer =
new Typer(context.make(context.tree, owner));
def atOwner(tree: Tree, owner: Symbol): Typer =
new Typer(context.make(tree, owner));
/** Types expression or definition `tree' */
def typed(tree: Tree): Tree =
typed(tree, EXPRmode, WildcardType);
/** Types expression `tree' with given prototype `pt' */
def typed(tree: Tree, pt: Type): Tree =
typed(tree, EXPRmode, pt);
/** Types qualifier `tree' of a select node. E.g. is tree occurs in acontext like `tree.m'. */
def typedQualifier(tree: Tree): Tree =
typed(tree, EXPRmode | QUALmode | POLYmode, WildcardType);
/** Types function part of an application */
def typedOperator(tree: Tree): Tree =
typed(tree, EXPRmode | FUNmode | POLYmode | TAPPmode, WildcardType);
/** Types a pattern with prototype `pt' */
def typedPattern(tree: Tree, pt: Type): Tree =
typed(tree, PATTERNmode, pt);
/** Types a (fully parameterized) type tree */
def typedType(tree: Tree): Tree =
typed(tree, TYPEmode, WildcardType);
/** Types a type constructor tree used in a new or supertype */
def typedTypeConstructor(tree: Tree): Tree = {
val result = typed(tree, TYPEmode | FUNmode, WildcardType);
if (!phase.erasedTypes && result.tpe.isInstanceOf[TypeRef] && !result.tpe.prefix.isStable)
error(tree.pos, result.tpe.prefix.toString() + " is not a legal prefix for a constructor");
result
}
def computeType(tree: Tree): Type = {
val tree1 = typed(tree);
transformed(tree) = tree1;
tree1.tpe
}
def transformedOrTyped(tree: Tree, pt: Type): Tree = transformed.get(tree) match {
case Some(tree1) => transformed -= tree; tree1
case None => typed(tree, pt)
}
/*
def convertToTypeTree(tree: Tree): Tree = tree match {
case TypeTree() => tree
case _ => TypeTree(tree.tpe)
}
*/
/* -- Views --------------------------------------------------------------- */
private def depoly(tp: Type): Type = tp match {
case PolyType(tparams, restpe) => restpe.subst(tparams, tparams map (t => WildcardType))
case _ => tp
}
private def typedImplicit(pos: int, info: ImplicitInfo, pt: Type, local: boolean): Tree =
if (isCompatible(depoly(info.tpe), pt)) {
var tree: Tree = EmptyTree;
def fail(reason: String): Tree = {
if (settings.debug.value)
log(tree.toString() + " is not a valid implicit value because:\n" + reason);
EmptyTree
}
try {
tree = Ident(info.name) setPos pos;
if (!local) tree setSymbol info.sym;
tree = typed1(tree, EXPRmode, pt);
if (settings.debug.value) log("typed implicit " + tree + ":" + tree.tpe + ", pt = " + pt);//debug
val tree1 = adapt(tree, EXPRmode, pt);
if (settings.debug.value) log("adapted implicit " + tree.symbol + ":" + tree1.tpe + " to " + pt);//debug
if (info.sym == tree.symbol) tree1
else fail("syms differ: " + tree.symbol + " " + info.sym)
} catch {
case ex: TypeError => fail(ex.getMessage())
}
} else EmptyTree;
private def inferImplicit(pos: int, pt: Type, isView: boolean, reportAmbiguous: boolean): Tree = {
if (util.Statistics.enabled) implcnt = implcnt + 1;
val startTime = if (util.Statistics.enabled) System.currentTimeMillis() else 0l;
def isBetter(sym1: Symbol, tpe1: Type, sym2: Symbol, tpe2: Type): boolean = {
sym2.isError ||
(sym1.owner != sym2.owner) && (sym1.owner isSubClass sym2.owner) && (tpe1 matches tpe2);
}
val tc = newTyper(context.makeImplicit(reportAmbiguous));
def searchImplicit(implicitInfoss: List[List[ImplicitInfo]], local: boolean): Tree = {
var iss = implicitInfoss;
var tree: Tree = EmptyTree;
while (tree == EmptyTree && !iss.isEmpty) {
var is = iss.head;
iss = iss.tail;
while (!is.isEmpty) {
tree = tc.typedImplicit(pos, is.head, pt, local);
if (settings.debug.value) log("tested " + is.head.sym + is.head.sym.locationString + ":" + is.head.tpe + "=" + tree);//debug
val is0 = is;
is = is.tail;
if (tree != EmptyTree) {
while (!is.isEmpty) {
val tree1 = tc.typedImplicit(pos, is.head, pt, local);
if (tree1 != EmptyTree) {
if (isBetter(is.head.sym, tree1.tpe, is0.head.sym, tree.tpe))
tree = tree1
else if (!isBetter(is0.head.sym, tree.tpe, is.head.sym, tree1.tpe))
error(
pos,
"ambiguous implicit value:\n" +
" both " + is0.head.sym + is0.head.sym.locationString + " of type " + tree.tpe +
"\n and " + is.head.sym + is.head.sym.locationString + " of type " + tree1.tpe +
(if (isView)
"\n are possible conversion functions from " +
pt.typeArgs(0) + " to " + pt.typeArgs(1)
else
"\n match expected type " + pt));
}
is = is.tail
}
}
}
}
tree
}
def implicitsOfType(tp: Type): List[List[ImplicitInfo]] = {
val tp1 = if (isFunctionType(tp)) intersectionType(tp.typeArgs.reverse) else tp;
tp1.baseClasses map implicitsOfClass;
}
def implicitsOfClass(clazz: Symbol): List[ImplicitInfo] =
clazz.initialize.linkedModule.moduleClass.info.decls.toList.filter(.hasFlag(IMPLICIT)) map
(sym => ImplicitInfo(sym.name, clazz.linkedModule.tpe.memberType(sym), sym));
var tree = searchImplicit(context.implicitss, true);
if (tree == EmptyTree) tree = searchImplicit(implicitsOfType(pt.widen), false);
if (util.Statistics.enabled) impltime = impltime + System.currentTimeMillis() - startTime;
tree
}
def applyImplicitArgs(tree: Tree): Tree = tree.tpe match {
case MethodType(formals, _) =>
def implicitArg(pt: Type) = {
val arg = inferImplicit(tree.pos, pt, false, true);
if (arg != EmptyTree) arg
else errorTree(tree, "no implicit argument matching parameter type " + pt + " was found.")
}
Apply(tree, formals map implicitArg) setPos tree.pos
}
}
}