diff --git a/compiler/frontend/src/org/jetbrains/kotlin/resolve/lazy/descriptors/LazyScriptClassMemberScope.kt b/compiler/frontend/src/org/jetbrains/kotlin/resolve/lazy/descriptors/LazyScriptClassMemberScope.kt
index 39a6aab0d8b..d7949b3681d 100644
--- a/compiler/frontend/src/org/jetbrains/kotlin/resolve/lazy/descriptors/LazyScriptClassMemberScope.kt
+++ b/compiler/frontend/src/org/jetbrains/kotlin/resolve/lazy/descriptors/LazyScriptClassMemberScope.kt
@@ -55,7 +55,8 @@ class LazyScriptClassMemberScope(
 
     private fun createScriptParameters(constructor: ConstructorDescriptorImpl): List<ValueParameterDescriptor> {
         val file = scriptDescriptor.scriptInfo.script.getContainingKtFile()
-        val scriptDefinition = KotlinScriptDefinitionProvider.getInstance(file.project).findScriptDefinition(file)
+        val scriptDefinition = KotlinScriptDefinitionProvider.getInstance(file.project).findScriptDefinition(file) ?:
+                    throw RuntimeException("file ${file.name} is not a script")
         return scriptDefinition.getScriptParameters(scriptDescriptor).mapIndexed { index, scriptParameter ->
             ValueParameterDescriptorImpl(
                     constructor, null, index, Annotations.EMPTY, scriptParameter.name, scriptParameter.type,
diff --git a/compiler/frontend/src/org/jetbrains/kotlin/resolve/lazy/descriptors/LazyScriptDescriptor.kt b/compiler/frontend/src/org/jetbrains/kotlin/resolve/lazy/descriptors/LazyScriptDescriptor.kt
index 56d3723e20a..5df1d003814 100644
--- a/compiler/frontend/src/org/jetbrains/kotlin/resolve/lazy/descriptors/LazyScriptDescriptor.kt
+++ b/compiler/frontend/src/org/jetbrains/kotlin/resolve/lazy/descriptors/LazyScriptDescriptor.kt
@@ -26,8 +26,8 @@ import org.jetbrains.kotlin.resolve.lazy.ResolveSession
 import org.jetbrains.kotlin.resolve.lazy.data.KtScriptInfo
 import org.jetbrains.kotlin.resolve.lazy.declarations.ClassMemberDeclarationProvider
 import org.jetbrains.kotlin.resolve.source.toSourceElement
+import org.jetbrains.kotlin.script.KotlinScriptDefinition
 import org.jetbrains.kotlin.script.KotlinScriptDefinitionProvider
-import org.jetbrains.kotlin.script.ScriptParameter
 import org.jetbrains.kotlin.script.ScriptPriorities
 import org.jetbrains.kotlin.types.KotlinType
 import org.jetbrains.kotlin.types.TypeSubstitutor
@@ -55,36 +55,33 @@ class LazyScriptDescriptor(
 
     override fun getPriority() = priority
 
+    private val scriptDefinition: KotlinScriptDefinition
+            by lazy {
+                val file = scriptInfo.script.getContainingKtFile()
+                KotlinScriptDefinitionProvider.getInstance(file.project).findScriptDefinition(file) ?:
+                    throw RuntimeException("file ${file.name} is not a script")
+            }
+
     override fun substitute(substitutor: TypeSubstitutor) = this
 
-    override fun <R, D> accept(visitor: DeclarationDescriptorVisitor<R, D>, data: D): R {
-        return visitor.visitScriptDescriptor(this, data)
-    }
+    override fun <R, D> accept(visitor: DeclarationDescriptorVisitor<R, D>, data: D): R =
+            visitor.visitScriptDescriptor(this, data)
 
-    override fun createMemberScope(
-            c: LazyClassContext,
-            declarationProvider: ClassMemberDeclarationProvider): LazyScriptClassMemberScope {
-        return LazyScriptClassMemberScope(
+    override fun createMemberScope( c: LazyClassContext, declarationProvider: ClassMemberDeclarationProvider): LazyScriptClassMemberScope =
+        LazyScriptClassMemberScope(
                 // Must be a ResolveSession for scripts
                 c as ResolveSession,
                 declarationProvider,
                 this,
                 c.trace
         )
-    }
 
     override fun getUnsubstitutedPrimaryConstructor() = super.getUnsubstitutedPrimaryConstructor()!!
 
-    override fun getInjectedSupertypes(): List<KotlinType>? {
-        val file = scriptInfo.script.getContainingKtFile()
-        val scriptDefinition = KotlinScriptDefinitionProvider.getInstance(file.project).findScriptDefinition(file)
-        val superclasses = scriptDefinition.getScriptSupertypes(this)
-        return if (superclasses.isEmpty()) null else superclasses
-    }
+    override fun getInjectedSupertypes(): List<KotlinType>? =
+            scriptDefinition.getScriptSupertypes(this).let { if (it.isEmpty()) null else it }
 
     override fun getScriptParametersToPassToSuperclass(): List<Pair<Name, KotlinType>> {
-        val file = scriptInfo.script.getContainingKtFile()
-        val scriptDefinition = KotlinScriptDefinitionProvider.getInstance(file.project).findScriptDefinition(file)
         val scriptParams = scriptDefinition.getScriptParameters(this)
         return scriptDefinition.getScriptParametersToPassToSuperclass(this).map { name ->
             Pair(name,
diff --git a/compiler/frontend/src/org/jetbrains/kotlin/script/KotlinScriptDefinitionProvider.kt b/compiler/frontend/src/org/jetbrains/kotlin/script/KotlinScriptDefinitionProvider.kt
index f4ec3626f2a..f5d060f278b 100644
--- a/compiler/frontend/src/org/jetbrains/kotlin/script/KotlinScriptDefinitionProvider.kt
+++ b/compiler/frontend/src/org/jetbrains/kotlin/script/KotlinScriptDefinitionProvider.kt
@@ -14,51 +14,35 @@
  * limitations under the License.
  */
 
-package org.jetbrains.kotlin.script;
+package org.jetbrains.kotlin.script
 
-import com.intellij.openapi.components.ServiceManager;
-import com.intellij.openapi.project.Project;
-import com.intellij.psi.PsiFile;
-import org.jetbrains.annotations.NotNull;
+import com.intellij.openapi.components.ServiceManager
+import com.intellij.openapi.project.Project
+import com.intellij.psi.PsiFile
 
-import java.util.ArrayList;
-import java.util.List;
+class KotlinScriptDefinitionProvider {
+    private val definitions: MutableList<KotlinScriptDefinition> = arrayListOf(StandardScriptDefinition)
 
-public class KotlinScriptDefinitionProvider {
-    private final List<KotlinScriptDefinition> definitions = new ArrayList<KotlinScriptDefinition>();
+    fun findScriptDefinition(psiFile: PsiFile): KotlinScriptDefinition? = definitions.firstOrNull { it.isScript(psiFile) }
 
-    public static KotlinScriptDefinitionProvider getInstance(Project project) {
-        return ServiceManager.getService(project, KotlinScriptDefinitionProvider.class);
+    fun isScript(psiFile: PsiFile): Boolean = findScriptDefinition(psiFile) != null
+
+    fun addScriptDefinition(scriptDefinition: KotlinScriptDefinition) {
+        definitions.add(0, scriptDefinition)
     }
 
-    public KotlinScriptDefinitionProvider() {
-        definitions.add(StandardScriptDefinition.INSTANCE);
+    fun setScriptDefinitions(definitions: List<KotlinScriptDefinition>) {
+        this.definitions.clear()
+        this.definitions.addAll(definitions)
     }
 
-    public KotlinScriptDefinition findScriptDefinition(PsiFile psiFile) {
-        for (KotlinScriptDefinition definition : definitions) {
-            if (definition.isScript(psiFile)) {
-                return definition;
-            }
-        }
-
-        return null;
+    fun removeScriptDefinition(scriptDefinition: KotlinScriptDefinition) {
+        definitions.remove(scriptDefinition)
     }
 
-    public boolean isScript(PsiFile psiFile) {
-        return findScriptDefinition(psiFile) != null;
-    }
-
-    public void addScriptDefinition(@NotNull KotlinScriptDefinition scriptDefinition) {
-        definitions.add(0, scriptDefinition);
-    }
-
-    public void removeScriptDefinition(@NotNull KotlinScriptDefinition scriptDefinition) {
-        definitions.remove(scriptDefinition);
-    }
-
-    public void setScriptDefinitions(@NotNull List<KotlinScriptDefinition> definitions) {
-        this.definitions.clear();
-        this.definitions.addAll(definitions);
+    companion object {
+        @JvmStatic
+        fun getInstance(project: Project): KotlinScriptDefinitionProvider =
+                ServiceManager.getService(project, KotlinScriptDefinitionProvider::class.java)
     }
 }