Apply suggestions from code review

Co-authored-by: Nicolas Stucki <nicolas.stucki@gmail.com>

Author: natsukagami

compiler/src/dotty/tools/dotc/ast/untpd.scala

@@ -76,7 +76,7 @@ object untpd extends Trees.Instance[Untyped] with UntypedTreeInfo {
     override def isType: Boolean = body.isType
   }
 
-  /** A function type or closure with `implicit`, `erased`, or `given` modifiers */
+  /** A function type or closure with `implicit` or `given` modifiers and information on which parameters are `erased` */
   class FunctionWithMods(args: List[Tree], body: Tree, val mods: Modifiers, val erasedParams: List[Boolean])(implicit @constructorOnly src: SourceFile)
     extends Function(args, body) {
       assert(args.length == erasedParams.length)

compiler/src/dotty/tools/dotc/core/tasty/TastyPrinter.scala

@@ -136,7 +136,6 @@ class TastyPrinter(bytes: Array[Byte]) {
             case METHODtype | POLYtype | TYPELAMBDAtype =>
               printTree()
               while (currentAddr.index < end.index && !isModifierTag(nextByte)) { printTree(); printName(); }
-              // read tags
               printTrees()
             case PARAMtype =>
               printNat(); printNat()

compiler/src/dotty/tools/dotc/printing/PlainPrinter.scala

@@ -129,7 +129,7 @@ class PlainPrinter(_ctx: Context) extends Printer {
     * (hence with `GlobalPrec` precedence).
     */
   protected def argsText(args: List[Type]): Text =
-    atPrec(GlobalPrec) { Text(args.map(argText(_)), ", ") }
+    atPrec(GlobalPrec) { Text(args.map(arg => argText(arg) ), ", ") }
 
   /** The longest sequence of refinement types, starting at given type
    *  and following parents.

compiler/src/dotty/tools/dotc/transform/ContextFunctionResults.scala

@@ -58,7 +58,7 @@ object ContextFunctionResults:
    */
   def contextResultsAreErased(sym: Symbol)(using Context): Boolean =
     def allErased(tp: Type): Boolean = tp.dealias match
-      case defn.ContextFunctionType(_, resTpe, erasedParams) => erasedParams.forall(_ == true) && allErased(resTpe)
+      case defn.ContextFunctionType(_, resTpe, erasedParams) => !erasedParams.contains(false) && allErased(resTpe)
       case _ => true
     contextResultCount(sym) > 0 && allErased(sym.info.finalResultType)
 

compiler/src/dotty/tools/dotc/transform/SpecializeFunctions.scala

@@ -70,7 +70,7 @@ class SpecializeFunctions extends MiniPhase {
   /** Dispatch to specialized `apply`s in user code when available */
   override def transformApply(tree: Apply)(using Context) =
     tree match {
-      case Apply(fun: NameTree, args) if fun.name == nme.apply && args.size <= 3 && fun.symbol.exists && fun.symbol.owner.isType =>
+      case Apply(fun: NameTree, args) if fun.name == nme.apply && args.size <= 3 && fun.symbol.maybeOwner.isType =>
         val argTypes = fun.tpe.widen.firstParamTypes.map(_.widenSingleton.dealias)
         val retType  = tree.tpe.widenSingleton.dealias
         val isSpecializable =