2 files changed, 13 insertions, 0 deletions
diff --git a/src/main/kotlin/moe/nea/ledger/ItemId.kt b/src/main/kotlin/moe/nea/ledger/ItemId.kt
index ade63fb..8211cd3 100644
--- a/src/main/kotlin/moe/nea/ledger/ItemId.kt
+++ b/src/main/kotlin/moe/nea/ledger/ItemId.kt
@@ -1,12 +1,16 @@
 package moe.nea.ledger
 
+import moe.nea.ledger.utils.NoSideEffects
+
 data class ItemId(
 	val string: String
 ) {
+	@NoSideEffects
 	fun singleItem(): Pair<ItemId, Double> {
 		return withStackSize(1)
 	}
 
+	@NoSideEffects
 	fun withStackSize(size: Number): Pair<ItemId, Double> {
 		return Pair(this, size.toDouble())
 	}
@@ -15,6 +19,7 @@ data class ItemId(
 	companion object {
 
 		@JvmStatic
+		@NoSideEffects
 		fun forName(string: String) = ItemId(string)
 		fun skill(skill: String) = ItemId("SKYBLOCK_SKILL_$skill")
 
diff --git a/src/main/kotlin/moe/nea/ledger/utils/NoSideEffects.java b/src/main/kotlin/moe/nea/ledger/utils/NoSideEffects.java
new file mode 100644
index 0000000..f432130
--- /dev/null
+++ b/src/main/kotlin/moe/nea/ledger/utils/NoSideEffects.java
@@ -0,0 +1,8 @@
+package moe.nea.ledger.utils;
+
+import kotlin.annotation.AnnotationRetention;
+import kotlin.annotation.Retention;
+
+@Retention(AnnotationRetention.BINARY)
+public @interface NoSideEffects {
+}