Vectors

Passing in vectors

You can pass a Rust std::vec::Vec into your contract method transparently. The following code calls a Sway contract method which accepts a Vec<SomeStruct<u32>>.

        let arg = vec![SomeStruct { a: 0 }, SomeStruct { a: 1 }];
        methods.struct_in_vec(arg.clone()).call().await?;

You can use a vector just like you would use any other type -- e.g. a [Vec<u32>; 2] or a SomeStruct<Vec<Bits256>> etc.

Returning vectors

Returning vectors from contract methods is supported transparently, with the caveat that you cannot have them nested inside another type. This limitation is temporary.

    let response = contract_methods.u8_in_vec(10).call().await?;
    assert_eq!(response.value, (0..10).collect::<Vec<_>>());

Note: you can still interact with contracts containing methods that return vectors nested inside another type, just not interact with the methods themselves