diff --git a/idea/src/org/jetbrains/jet/plugin/refactoring/extractFunction/ExtractionDescriptor.kt b/idea/src/org/jetbrains/jet/plugin/refactoring/extractFunction/ExtractionDescriptor.kt
index 8ea801675c4..b2dcc422396 100644
--- a/idea/src/org/jetbrains/jet/plugin/refactoring/extractFunction/ExtractionDescriptor.kt
+++ b/idea/src/org/jetbrains/jet/plugin/refactoring/extractFunction/ExtractionDescriptor.kt
@@ -43,11 +43,11 @@ trait Parameter {
     val parameterTypeCandidates: List<JetType>
     val receiverCandidate: Boolean
 
-    val nameForRef: String get() = mirrorVarName ?: name
-
     fun copy(name: String, parameterType: JetType): Parameter
 }
 
+val Parameter.nameForRef: String get() = mirrorVarName ?: name
+
 data class TypeParameter(
         val originalDeclaration: JetTypeParameter,
         val originalConstraints: List<JetTypeConstraint>