diff --git a/compiler/frontend/src/org/jetbrains/kotlin/psi/psiUtil/jetPsiUtil.kt b/compiler/frontend/src/org/jetbrains/kotlin/psi/psiUtil/jetPsiUtil.kt
index 4b1adbaa06a..81108c2beb7 100644
--- a/compiler/frontend/src/org/jetbrains/kotlin/psi/psiUtil/jetPsiUtil.kt
+++ b/compiler/frontend/src/org/jetbrains/kotlin/psi/psiUtil/jetPsiUtil.kt
@@ -129,7 +129,7 @@ public fun JetDeclaration.isOverridable(): Boolean {
         hasModifier(JetTokens.ABSTRACT_KEYWORD) || hasModifier(JetTokens.OPEN_KEYWORD) || hasModifier(JetTokens.OVERRIDE_KEYWORD)
 }
 
-public fun PsiElement.isExtensionDeclaration(): Boolean {
+public fun JetDeclaration.isExtensionDeclaration(): Boolean {
     val callable: JetCallableDeclaration? = when (this) {
         is JetNamedFunction, is JetProperty -> this as JetCallableDeclaration
         is JetPropertyAccessor -> getNonStrictParentOfType<JetProperty>()
@@ -139,7 +139,7 @@ public fun PsiElement.isExtensionDeclaration(): Boolean {
     return callable?.getReceiverTypeReference() != null
 }
 
-public fun PsiElement.isObjectLiteral(): Boolean = this is JetObjectDeclaration && isObjectLiteral()
+public fun JetClassOrObject.isObjectLiteral(): Boolean = this is JetObjectDeclaration && isObjectLiteral()
 
 //TODO: git rid of this method
 public fun PsiElement.deleteElementAndCleanParent() {
diff --git a/compiler/light-classes/src/org/jetbrains/kotlin/asJava/lightClassUtils.kt b/compiler/light-classes/src/org/jetbrains/kotlin/asJava/lightClassUtils.kt
index ed9beb4c0a3..faa1b6382c9 100644
--- a/compiler/light-classes/src/org/jetbrains/kotlin/asJava/lightClassUtils.kt
+++ b/compiler/light-classes/src/org/jetbrains/kotlin/asJava/lightClassUtils.kt
@@ -70,7 +70,7 @@ public fun JetParameter.toPsiParameter(): PsiParameter? {
 
     val paramIndex = paramList.getParameters().indexOf(this)
     val owner = paramList.getParent()
-    val lightParamIndex = if (owner != null && owner.isExtensionDeclaration()) paramIndex + 1 else paramIndex
+    val lightParamIndex = if (owner is JetDeclaration && owner.isExtensionDeclaration()) paramIndex + 1 else paramIndex
 
     val method: PsiMethod? = when (owner) {
         is JetFunction -> LightClassUtil.getLightClassMethod(owner)
diff --git a/idea/src/org/jetbrains/kotlin/idea/refactoring/move/moveUtils.kt b/idea/src/org/jetbrains/kotlin/idea/refactoring/move/moveUtils.kt
index 159ad1f1a57..fcbcb20a084 100644
--- a/idea/src/org/jetbrains/kotlin/idea/refactoring/move/moveUtils.kt
+++ b/idea/src/org/jetbrains/kotlin/idea/refactoring/move/moveUtils.kt
@@ -166,7 +166,7 @@ fun createMoveUsageInfoIfPossible(
     val endOffset = range.getEndOffset()
 
     if (reference is JetReference
-        && referencedElement.namedUnwrappedElement!!.isExtensionDeclaration()
+        && (referencedElement.namedUnwrappedElement as? JetDeclaration)?.isExtensionDeclaration() ?: false
         && element.getNonStrictParentOfType<JetImportDirective>() == null) {
         return MoveRenameUsageInfoForExtension(
                 element, reference, startOffset, endOffset, referencedElement, element.getContainingFile()!!, addImportToOriginalFile
diff --git a/idea/src/org/jetbrains/kotlin/idea/refactoring/safeDelete/utils.kt b/idea/src/org/jetbrains/kotlin/idea/refactoring/safeDelete/utils.kt
index c281983b18d..1ad062fa4b3 100644
--- a/idea/src/org/jetbrains/kotlin/idea/refactoring/safeDelete/utils.kt
+++ b/idea/src/org/jetbrains/kotlin/idea/refactoring/safeDelete/utils.kt
@@ -16,16 +16,15 @@
 
 package org.jetbrains.kotlin.idea.refactoring.safeDelete
 
-import com.intellij.psi.PsiMethod
 import com.intellij.psi.PsiElement
-import org.jetbrains.kotlin.lexer.JetTokens
+import com.intellij.psi.PsiMethod
 import com.intellij.psi.search.searches.OverridingMethodsSearch
 import org.jetbrains.kotlin.asJava.unwrapped
+import org.jetbrains.kotlin.lexer.JetTokens
 import org.jetbrains.kotlin.psi.*
-import org.jetbrains.kotlin.psi.psiUtil.*
 
 public fun PsiElement.canDeleteElement(): Boolean {
-    if (isObjectLiteral()) return false
+    if (this is JetObjectDeclaration && isObjectLiteral()) return false
 
     if (this is JetParameter) {
         val parameterList = getParent() as? JetParameterList ?: return false