retrieveData

inline fun <T : Any> ItemStack.retrieveData(key: Key): T?
inline fun <T : Any> ItemStack.retrieveData(addon: Addon, key: String): T?
inline fun <T : Any> ItemStack.retrieveData(namespace: String, key: String): T?
inline fun <T : Any> ItemStack.retrieveData(key: Key): T?
inline fun <T : Any> ItemStack.retrieveData(addon: Addon, key: String): T?
inline fun <T : Any> ItemStack.retrieveData(namespace: String, key: String): T?