Make all orElse methods inline methods

Make all orElse methods that take a call-by-name argument inline methods.

Author: odersky

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

@@ -174,7 +174,7 @@ object Trees {
     def toList: List[Tree[T]] = this :: Nil
 
     /** if this tree is the empty tree, the alternative, else this tree */
-    def orElse[U >: Untyped <: T](that: => Tree[U]): Tree[U] =
+    inline def orElse[U >: Untyped <: T](inline that: Tree[U]): Tree[U] =
       if (this eq genericEmptyTree) that else this
 
     /** The number of nodes in this tree */

compiler/src/dotty/tools/dotc/core/Denotations.scala

@@ -237,7 +237,7 @@ object Denotations {
     def mapInfo(f: Type => Type)(using Context): Denotation
 
     /** If this denotation does not exist, fallback to alternative */
-    final def orElse(that: => Denotation): Denotation = if (this.exists) this else that
+    inline def orElse(inline that: Denotation): Denotation = if (this.exists) this else that
 
     /** The set of alternative single-denotations making up this denotation */
     final def alternatives: List[SingleDenotation] = altsWith(alwaysTrue)
@@ -596,7 +596,7 @@ object Denotations {
     def mapInfo(f: Type => Type)(using Context): SingleDenotation =
       derivedSingleDenotation(symbol, f(info))
 
-    def orElse(that: => SingleDenotation): SingleDenotation = if (this.exists) this else that
+    inline def orElse(inline that: SingleDenotation): SingleDenotation = if (this.exists) this else that
 
     def altsWith(p: Symbol => Boolean): List[SingleDenotation] =
       if (exists && p(symbol)) this :: Nil else Nil

compiler/src/dotty/tools/dotc/core/Symbols.scala

@@ -239,7 +239,7 @@ object Symbols {
       }
 
     /** This symbol, if it exists, otherwise the result of evaluating `that` */
-    def orElse(that: => Symbol)(using Context): Symbol =
+    inline def orElse(inline that: Symbol)(using Context): Symbol =
       if (this.exists) this else that
 
     /** If this symbol satisfies predicate `p` this symbol, otherwise `NoSymbol` */