Improve doc comments

Author: odersky

src/dotty/tools/dotc/core/SymDenotations.scala

@@ -386,7 +386,7 @@ object SymDenotations {
     /** Is symbol a primitive value class? */
     def isPrimitiveValueClass(implicit ctx: Context) = defn.ScalaValueClasses contains symbol
 
-    /** Is symbol a primitive value class? */
+    /** Is symbol a primitive numeric value class? */
     def isNumericValueClass(implicit ctx: Context) = defn.ScalaNumericValueClasses contains symbol
 
     /** Is symbol a phantom class for which no runtime representation exists? */

src/dotty/tools/dotc/typer/Applications.scala

@@ -1057,6 +1057,9 @@ trait Applications extends Compatibility { self: Typer =>
     else ts
   }
 
+  /** If `trees` all have numeric value types, and they do not have all the same type,
+   *  pick a common numeric supertype and convert all trees to this type.
+   */
   def harmonize(trees: List[Tree])(implicit ctx: Context): List[Tree] = {
     def adapt(tree: Tree, pt: Type): Tree = tree match {
       case cdef: CaseDef => tpd.cpy.CaseDef(cdef)(body = adapt(cdef.body, pt))
@@ -1065,6 +1068,9 @@ trait Applications extends Compatibility { self: Typer =>
     harmonizeWith(trees)(_.tpe, adapt)
   }
 
+  /** If all `types` are numeric value types, and they are not all the same type,
+   *  pick a common numeric supertype and return it instead of every original type.
+   */
   def harmonizeTypes(tpes: List[Type])(implicit ctx: Context): List[Type] =
     harmonizeWith(tpes)(identity, (tp, pt) => pt)
 }