Add comment

odersky · odersky · commit c812c5dc0c59 · 2021-02-10T15:10:30.000+01:00
diff --git a/compiler/src/dotty/tools/dotc/typer/Applications.scala b/compiler/src/dotty/tools/dotc/typer/Applications.scala
@@ -1897,7 +1897,8 @@ trait Applications extends Compatibility {
     }
 
     /** The type of alternative `alt` after instantiating its first parameter
-     *  clause with `argTypes`.
+     *  clause with `argTypes`. In addition, if the resulting type is a PolyType
+     *  and `typeArgs` matches its parameter list, instantiate the result with `typeArgs`.
      */
     def skipParamClause(argTypes: List[Type], typeArgs: List[Type])(alt: TermRef): Type =
       def skip(tp: Type): Type = tp match {

Original file line number	Diff line number	Diff line change
`@@ -1897,7 +1897,8 @@ trait Applications extends Compatibility {`
`1897`	`1897`	`}`
`1898`	`1898`
`1899`	`1899`	/** The type of alternative `alt` after instantiating its first parameter
`1900`		- * clause with `argTypes`.
	`1900`	+ * clause with `argTypes`. In addition, if the resulting type is a PolyType
	`1901`	+ * and `typeArgs` matches its parameter list, instantiate the result with `typeArgs`.
`1901`	`1902`	`*/`
`1902`	`1903`	`def skipParamClause(argTypes: List[Type], typeArgs: List[Type])(alt: TermRef): Type =`
`1903`	`1904`	`def skip(tp: Type): Type = tp match {`