``` ``` morph_nat_as_u8_to_u16 () ℕ ~ native.UInt8 --> ℕ ~ native.UInt16 ```*dst = *src;``` morph_nat_as_u16_to_u32 () ℕ ~ native.UInt16 --> ℕ ~ native.UInt32 ```*dst = *src;``` morph_nat_as_u32_to_u64 () ℕ ~ native.UInt32 --> ℕ ~ native.UInt64 ```*dst = *src;```