# Module `iota::types` IOTA types helpers and utilities - [Function `is_one_time_witness`](#iota_types_is_one_time_witness)

## Function `is_one_time_witness` Tests if the argument type is a one-time witness, that is a type with only one instantiation across the entire code base.

public fun is_one_time_witness<T: drop>(_: &T): bool

Implementation

public native fun is_one_time_witness<T: drop>(_: &T): bool;