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+### `value.?let` or `if (value != null)`
+
+Is really better to use
+
+```kotlin
+value?.let {
+     // some block
+}
+```
+
+then
+
+```kotlin
+if (value != null) {
+    // some block
+}
+```
+
+There is no return value so block is NOT expression.
+
+### Don't use anonymous class implementation
+```kotlin
+val value = object : Type {
+    // implementation
+}
+```
+