Added some more methods as infix tree operations:

asInstance/isInstance/ensureConforms/and/or.

They replace some former "mk..." methods.

Author: odersky

src/dotty/tools/dotc/ast/tpd.scala

@@ -405,6 +405,21 @@ object tpd extends Trees.Instance[Type] with TypedTreeInfo {
 
     def appliedToTypeTrees(targs: List[Tree])(implicit ctx: Context): Tree =
       if (targs.isEmpty) tree else TypeApply(tree, targs)
+
+    def isInstance(tp: Type)(implicit ctx: Context): Tree =
+      tree.select(defn.Any_isInstanceOf).appliedToType(tp)
+
+    def asInstance(tp: Type)(implicit ctx: Context): Tree =
+      tree.select(defn.Any_asInstanceOf).appliedToType(tp)
+
+    def ensureConforms(tp: Type)(implicit ctx: Context): Tree =
+      if (tree.tpe <:< tp) tree else asInstance(tp)
+
+    def and(that: Tree)(implicit ctx: Context): Tree =
+      tree.select(defn.Boolean_&&).appliedTo(that)
+
+    def or(that: Tree)(implicit ctx: Context): Tree =
+      tree.select(defn.Boolean_||).appliedTo(that)
   }
 
   implicit class ListOfTreeDecorator(val xs: List[tpd.Tree]) extends AnyVal {
@@ -648,15 +663,6 @@ object tpd extends Trees.Instance[Type] with TypedTreeInfo {
 
   def runtimeCall(name: TermName, args: List[Tree])(implicit ctx: Context): Tree = ???
 
-  def mkAnd(tree1: Tree, tree2: Tree)(implicit ctx: Context) =
-    tree1.select(defn.Boolean_and).appliedTo(tree2)
-
-  def mkAsInstanceOf(tree: Tree, pt: Type)(implicit ctx: Context): Tree =
-    tree.select(defn.Any_asInstanceOf).appliedToType(pt)
-
-  def ensureConforms(tree: Tree, pt: Type)(implicit ctx: Context): Tree =
-    if (tree.tpe <:< pt) tree else mkAsInstanceOf(tree, pt)
-
   // ensure that constructors are fully applied?
   // ensure that normal methods are fully applied?
 

src/dotty/tools/dotc/transform/Erasure.scala

@@ -157,7 +157,7 @@ object Erasure {
           cast(runtimeCall(nme.toObjectArray, tree :: Nil), pt)
         case _ =>
           ctx.log(s"casting from ${tree.showSummary}: ${tree.tpe.show} to ${pt.show}")
-          mkAsInstanceOf(tree, pt)
+          tree.asInstance(pt)
       }
     }
 

src/dotty/tools/dotc/transform/SuperAccessors.scala

@@ -276,7 +276,7 @@ class SuperAccessors extends MacroTransform with IdentityDenotTransformer { this
                             .installAfter(thisTransformer)
                           val superAcc =
                             Super(This(currentClass), tpnme.EMPTY, inConstrCall = false).select(alias)
-                          DefDef(sym, ensureConforms(superAcc, sym.info.widen))
+                          DefDef(sym, superAcc.ensureConforms(sym.info.widen))
                         }
                         return forwarder(ctx.withPhase(thisTransformer.next))
                       }

src/dotty/tools/dotc/transform/TypeTestsCasts.scala

@@ -59,7 +59,7 @@ class TypeTestsCasts extends MiniPhaseTransform {
                   case _ =>
                     erased2 match {
                       case Literal(Constant(true)) => erased1
-                      case _ => mkAnd(erased1, erased2)
+                      case _ => erased1 and erased2
                     }
                 }
               }
@@ -68,7 +68,7 @@ class TypeTestsCasts extends MiniPhaseTransform {
                 runtimeCall(nme.isArray, arg :: Literal(Constant(ndims)) :: Nil)
               if (ndims == 1) isArrayTest(qual)
               else evalOnce(qual) { qual1 =>
-                mkAnd(derivedTree(qual1, defn.Any_isInstanceOf, qual1.tpe), isArrayTest(qual1))
+                derivedTree(qual1, defn.Any_isInstanceOf, qual1.tpe) and isArrayTest(qual1)
               }
             case _ =>
               derivedTree(expr, defn.Any_isInstanceOf, argType)