simplifies flag API

Flag ops now only include | and hasFlag,
flag bearer ops now only include flags and hasFlag.

These abstractions are enough to implement everything else,
so let's stick to them for the sake of minimalism.

8 files changed, 14 insertions, 42 deletions

diff --git a/src/library/scala/reflect/base/Base.scala b/src/library/scala/reflect/base/Base.scala
index ddb502fd44..6d13395019 100644
--- a/src/library/scala/reflect/base/Base.scala
+++ b/src/library/scala/reflect/base/Base.scala
@@ -234,7 +234,6 @@ class Base extends Universe { self =>
                   override val privateWithin: Name,
                   override val annotations: List[Tree]) extends ModifiersBase {
     def hasFlag(flags: FlagSet) = (this.flags & flags) != 0
-    def hasAllFlags(flags: FlagSet) = (flags & ~this.flags) == 0
   }
 
   implicit val ModifiersTag = ClassTag[Modifiers](classOf[Modifiers])
diff --git a/src/library/scala/reflect/base/FlagSets.scala b/src/library/scala/reflect/base/FlagSets.scala
index 57946d0f27..43de9970c0 100644
--- a/src/library/scala/reflect/base/FlagSets.scala
+++ b/src/library/scala/reflect/base/FlagSets.scala
@@ -13,5 +13,11 @@ trait FlagSets { self: Universe =>
 
   /** The empty set of flags */
   val NoFlags: FlagSet
+
+  /** The base API all flag bearers support */
+  trait HasFlagsBase {
+    def flags: FlagSet
+    def hasFlag(flags: FlagSet): Boolean
+  }
 }
 
diff --git a/src/library/scala/reflect/base/Trees.scala b/src/library/scala/reflect/base/Trees.scala
index 2814450ae3..ab03b7a89f 100644
--- a/src/library/scala/reflect/base/Trees.scala
+++ b/src/library/scala/reflect/base/Trees.scala
@@ -1356,10 +1356,7 @@ trait Trees { self: Universe =>
   implicit val ModifiersTag: ClassTag[Modifiers]
 
   /** ... */
-  abstract class ModifiersBase {
-    def flags: FlagSet
-    def hasFlag(flags: FlagSet): Boolean
-    def hasAllFlags(flags: FlagSet): Boolean
+  abstract class ModifiersBase extends HasFlagsBase {
     def privateWithin: Name  // default: EmptyTypeName
     def annotations: List[Tree] // default: List()
     def mapAnnotations(f: List[Tree] => List[Tree]): Modifiers =
diff --git a/src/reflect/scala/reflect/api/FlagSets.scala b/src/reflect/scala/reflect/api/FlagSets.scala
index 969176d641..c56de49962 100644
--- a/src/reflect/scala/reflect/api/FlagSets.scala
+++ b/src/reflect/scala/reflect/api/FlagSets.scala
@@ -9,8 +9,7 @@ trait FlagSets { self: Universe =>
 
   trait FlagOps extends Any {
     def | (right: FlagSet): FlagSet
-    def & (right: FlagSet): FlagSet
-    def containsAll (right: FlagSet): Boolean
+    def hasFlag(flags: FlagSet): Boolean
   }
 
   implicit def addFlagOps(left: FlagSet): FlagOps
@@ -19,8 +18,6 @@ trait FlagSets { self: Universe =>
 
   type FlagValues >: Null <: FlagValuesApi
 
-  // [Eugene++] any other flags we would like to expose?
-
   trait FlagValuesApi {
 
     /** Flag indicating that symbol or tree represents a trait */
@@ -104,9 +101,5 @@ trait FlagSets { self: Universe =>
     /** Flag indicating that trait has neither method implementations nor fields.
      *  This means the trait can be represented as a Java interface. */
     val INTERFACE: FlagSet
-
-    def union(flags: FlagSet*): FlagSet
-    def intersection(flag: FlagSet*): FlagSet
-    def containsAll(superset: FlagSet, subset: FlagSet): Boolean
   }
 }
diff --git a/src/reflect/scala/reflect/api/Symbols.scala b/src/reflect/scala/reflect/api/Symbols.scala
index c94c796279..84341177ca 100644
--- a/src/reflect/scala/reflect/api/Symbols.scala
+++ b/src/reflect/scala/reflect/api/Symbols.scala
@@ -12,15 +12,8 @@ trait Symbols extends base.Symbols { self: Universe =>
   override type FreeTermSymbol >: Null <: TermSymbol with FreeTermSymbolApi
   override type FreeTypeSymbol >: Null <: TypeSymbol with FreeTypeSymbolApi
 
-  trait HasFlagsApi {
-    def flags: FlagSet
-    def hasFlag(fs: FlagSet): Boolean
-    def hasAllFlags(fs: FlagSet): Boolean
-    def flagString: String
-  }
-
   /** The API of symbols */
-  trait SymbolApi extends SymbolBase with HasFlagsApi { this: Symbol =>
+  trait SymbolApi extends SymbolBase with HasFlagsBase { this: Symbol =>
 
     /** The position of this symbol
      */
@@ -228,14 +221,14 @@ trait Symbols extends base.Symbols { self: Universe =>
   }
 
   /** The API of term symbols */
-  trait TermSymbolApi extends SymbolApi with HasFlagsApi with TermSymbolBase { this: TermSymbol =>
+  trait TermSymbolApi extends SymbolApi with TermSymbolBase { this: TermSymbol =>
     /** The overloaded alternatives of this symbol */
     def alternatives: List[Symbol]
 
   }
 
   /** The API of type symbols */
-  trait TypeSymbolApi extends SymbolApi with HasFlagsApi with TypeSymbolBase { this: TypeSymbol =>
+  trait TypeSymbolApi extends SymbolApi with TypeSymbolBase { this: TypeSymbol =>
     /** Is the type parameter represented by this symbol contravariant?
      */
     def isContravariant : Boolean
diff --git a/src/reflect/scala/reflect/api/Trees.scala b/src/reflect/scala/reflect/api/Trees.scala
index 2d130daa4e..28dd764c70 100644
--- a/src/reflect/scala/reflect/api/Trees.scala
+++ b/src/reflect/scala/reflect/api/Trees.scala
@@ -683,7 +683,7 @@ trait Trees extends base.Trees { self: Universe =>
 
   type Modifiers >: Null <: ModifiersApi
 
-  abstract class ModifiersApi extends ModifiersBase with HasFlagsApi
+  abstract class ModifiersApi extends ModifiersBase
 
 }
 
diff --git a/src/reflect/scala/reflect/internal/FlagSets.scala b/src/reflect/scala/reflect/internal/FlagSets.scala
index 0354d2513c..6e77741355 100644
--- a/src/reflect/scala/reflect/internal/FlagSets.scala
+++ b/src/reflect/scala/reflect/internal/FlagSets.scala
@@ -13,8 +13,7 @@ trait FlagSets extends api.FlagSets { self: SymbolTable =>
 
   private class FlagOpsImpl(left: Long) extends FlagOps {
     def | (right: Long): Long = left | right
-    def & (right: Long): Long = left & right
-    def containsAll (right: Long): Boolean = (right & ~left) == 0
+    def hasFlag(right: Long): Boolean = (left & right) != 0
   }
 
   val NoFlags: FlagSet = 0L
@@ -47,20 +46,5 @@ trait FlagSets extends api.FlagSets { self: SymbolTable =>
     val CONTRAVARIANT : FlagSet = Flags.CONTRAVARIANT
     val DEFAULTPARAM  : FlagSet = Flags.DEFAULTPARAM
     val INTERFACE     : FlagSet = Flags.INTERFACE
-
-    def union(flags: FlagSet*): FlagSet = {
-      var acc = 0L
-      for (flag <- flags) acc |= flag
-      acc
-    }
-
-    def intersection(flags: FlagSet*): FlagSet = {
-      var acc = -1L
-      for (flag <- flags) acc &= flag
-      acc
-    }
-
-    def containsAll(superset: FlagSet, subset: FlagSet): Boolean =
-      (subset & ~superset) == 0
   }
 }
diff --git a/src/reflect/scala/reflect/internal/Printers.scala b/src/reflect/scala/reflect/internal/Printers.scala
index 18f9928124..8571ac1110 100644
--- a/src/reflect/scala/reflect/internal/Printers.scala
+++ b/src/reflect/scala/reflect/internal/Printers.scala
@@ -670,7 +670,7 @@ trait Printers extends api.Printers { self: SymbolTable =>
     if (flags == NoFlags) nme.NoFlags.toString
     else {
       val s_flags = new collection.mutable.ListBuffer[String]
-      for (i <- 0 to 63 if (flags containsAll (1L << i)))
+      for (i <- 0 to 63 if (flags hasFlag (1L << i)))
         s_flags += flagToString(1L << i).replace("<", "").replace(">", "").toUpperCase
       s_flags mkString " | "
     }