How to create a tuple type using polkadot.js api

Question

I am trying to create a tuple. I know we can create an enum by defining the type as

   MyEnum: {
            _enum: {
                'account': String,
                'accountId': 'u128'

            }
        }

similarly how can i create a tuple type

(account, accountId)

Answer 1

Tuple types are specified in the same way they are in Rust, i.e. (AccountId, u32) will yield a tuple with AccountId and u32. These are all string values, i.e.

MyTuple: "(AccountId, u32)",
MyEnum: {
  _enum: {
    Foo: "AccountId",
    Bar: "(AccountId, u64)",
    Baz: "String"
  }
}

As indicated in a comment, with current Substrate nodes you should not need to define types, these are supplied in the metadata. (There is one caveat - when used over RPCs, these are not available and needs to be manually specified alongside the RPC definitions)