diff --git a/translator/src/main/kotlin/org/kotlinnative/translator/ProjectTranslator.kt b/translator/src/main/kotlin/org/kotlinnative/translator/ProjectTranslator.kt
index c9593f55403..8974b5042da 100644
--- a/translator/src/main/kotlin/org/kotlinnative/translator/ProjectTranslator.kt
+++ b/translator/src/main/kotlin/org/kotlinnative/translator/ProjectTranslator.kt
@@ -23,8 +23,8 @@ class ProjectTranslator(val files: List<KtFile>,
 
     fun addFunctionDeclarations(file: KtFile) {
         val variableManager = VariableManager(state.globalVariableCollection)
-        for (declaration in file.declarations.filter { it is KtNamedFunction }) {
-            val function = FunctionCodegen(state, variableManager, declaration as KtNamedFunction, codeBuilder)
+        for (declaration in file.declarations.filterIsInstance<KtNamedFunction>()) {
+            val function = FunctionCodegen(state, variableManager, declaration, codeBuilder)
             if (function.external) {
                 state.externalFunctions.put(function.fullName, function)
             } else {
@@ -35,24 +35,24 @@ class ProjectTranslator(val files: List<KtFile>,
 
     fun addClassDeclarations(file: KtFile) {
         val variableManager = VariableManager(state.globalVariableCollection)
-        for (declaration in file.declarations.filter { it is KtClass }) {
-            val codegen = ClassCodegen(state, variableManager, declaration as KtClass, codeBuilder)
+        for (declaration in file.declarations.filterIsInstance<KtClass>()) {
+            val codegen = ClassCodegen(state, variableManager, declaration, codeBuilder)
             state.classes.put(codegen.structName, codegen)
         }
     }
 
     fun addPropertyDeclarations(file: KtFile) {
         val variableManager = VariableManager(state.globalVariableCollection)
-        for (declaration in file.declarations.filter { it is KtProperty }) {
-            val property = PropertyCodegen(state, variableManager, declaration as KtProperty, codeBuilder)
+        for (declaration in file.declarations.filterIsInstance<KtProperty>()) {
+            val property = PropertyCodegen(state, variableManager, declaration, codeBuilder)
             state.properties.put(declaration.name!!, property)
         }
     }
 
     fun addObjectDeclarations(file: KtFile) {
         val variableManager = VariableManager(state.globalVariableCollection)
-        for (declaration in file.declarations.filter { it is KtObjectDeclaration }) {
-            val codegen = ObjectCodegen(state, variableManager, declaration as KtObjectDeclaration, codeBuilder)
+        for (declaration in file.declarations.filterIsInstance<KtObjectDeclaration>()) {
+            val codegen = ObjectCodegen(state, variableManager, declaration, codeBuilder)
             state.objects.put(codegen.structName, codegen)
         }
     }
diff --git a/translator/src/main/kotlin/org/kotlinnative/translator/codegens/StructCodegen.kt b/translator/src/main/kotlin/org/kotlinnative/translator/codegens/StructCodegen.kt
index e92d9467f76..92021d7b054 100644
--- a/translator/src/main/kotlin/org/kotlinnative/translator/codegens/StructCodegen.kt
+++ b/translator/src/main/kotlin/org/kotlinnative/translator/codegens/StructCodegen.kt
@@ -39,8 +39,8 @@ abstract class StructCodegen(val state: TranslationState,
 
     open fun prepareForGenerate() {
         generateStruct()
-        classOrObject.declarations.filter { it is KtNamedFunction }.map {
-            val function = FunctionCodegen(state, variableManager, it as KtNamedFunction, codeBuilder)
+        classOrObject.declarations.filterIsInstance<KtNamedFunction>().map {
+            val function = FunctionCodegen(state, variableManager, it, codeBuilder)
             methods.put(function.name, function)
         }
     }
@@ -104,11 +104,11 @@ abstract class StructCodegen(val state: TranslationState,
     }
 
     private fun generateEnumFields() {
-        val enumEntries = classOrObject.declarations.filter { it is KtEnumEntry }
+        val enumEntries = classOrObject.declarations.filterIsInstance<KtEnumEntry>()
 
         for (declaration in enumEntries) {
             val name = declaration.name!!
-            val initializer = (declaration as KtEnumEntry).initializerList!!.initializers[0]
+            val initializer = declaration.initializerList!!.initializers[0]
             val arguments = (initializer as KtSuperTypeCallEntry).valueArguments.map { it.getArgumentExpression()!!.text }
 
             val field = codeBuilder.getNewVariable(type, scope = LLVMVariableScope())