diff --git a/src/commonMain/kotlin/ru/landgrafhomyak/utility/highlevel_try_finally/safe_autoclose.kt b/src/commonMain/kotlin/ru/landgrafhomyak/utility/highlevel_try_finally/safe_autoclose.kt
index 0d14a03..239852a 100644
--- a/src/commonMain/kotlin/ru/landgrafhomyak/utility/highlevel_try_finally/safe_autoclose.kt
+++ b/src/commonMain/kotlin/ru/landgrafhomyak/utility/highlevel_try_finally/safe_autoclose.kt
@@ -1,22 +1,47 @@
 package ru.landgrafhomyak.utility.highlevel_try_finally
 
-inline fun <R> safeAutoClose(
+import kotlin.contracts.InvocationKind
+import kotlin.contracts.contract
+
+inline fun <R> safeAutoClose1(
 	finally: () -> Unit,
 	action: () -> R
-): R = safeAutoClose(onError = finally, onSuccess = finally, onCrossReturn = finally, action = action)
+): R  {
+	@Suppress("WRONG_INVOCATION_KIND")
+	contract {
+		callsInPlace(action, InvocationKind.EXACTLY_ONCE)
+		callsInPlace(finally, InvocationKind.EXACTLY_ONCE)
+	}
+	return safeAutoClose3(onError = finally, onSuccess = finally, onCrossReturn = finally, action = action)
+}
 
-inline fun <R> safeAutoClose(
+inline fun <R> safeAutoClose2(
 	onError: () -> Unit = {},
 	onSuccess: () -> Unit = {},
 	action: () -> R
-): R = safeAutoClose(onError = onError, onSuccess = onSuccess, onCrossReturn = onSuccess, action = action)
+): R  {
+	@Suppress("WRONG_INVOCATION_KIND")
+	contract {
+		callsInPlace(action, InvocationKind.EXACTLY_ONCE)
+		callsInPlace(onError, InvocationKind.AT_MOST_ONCE)
+		callsInPlace(onSuccess, InvocationKind.AT_MOST_ONCE)
+	}
+	return safeAutoClose3(onError = onError, onSuccess = onSuccess, onCrossReturn = onSuccess, action = action)
+}
 
-inline fun <R> safeAutoClose(
+inline fun <R> safeAutoClose3(
 	onError: () -> Unit = {},
 	onSuccess: () -> Unit = {},
 	onCrossReturn: () -> Unit = {},
 	action: () -> R
 ): R {
+	contract {
+		callsInPlace(action, InvocationKind.EXACTLY_ONCE)
+		callsInPlace(onError, InvocationKind.AT_MOST_ONCE)
+		callsInPlace(onSuccess, InvocationKind.AT_MOST_ONCE)
+		callsInPlace(onCrossReturn, InvocationKind.AT_MOST_ONCE)
+	}
+
 	val ret: R
 	var wasError = false
 	var crossReturned = true