are there any best practices/idioms in regards to object configuration/building?

Let's say I want to configure a TwitterClient that requires a username and a password that is stored in a separate object TwitterConfiguration

a) the basic approach (either separate sends or via cascade, that is not relevant here)

client := TwitterClient new.

client configuration username: 'XX'.

client configuration password: 'YY'.

b) #in: ...

It feels a bit more organized as it basically groups related operations together.

Also maybe avoiding demeter a bit?

client := TwitterClient new.

client configuration in: [ :config |

config username: 'XX'.

config password: 'YY'.

].

c) custom #somethingDo: method that basically does #in:

Again, feels more organized. Additionally one could perform some validation afterwards (to make sure the credentials are ok or whatever).

client := TwitterClient new.

client configurationDo: [ :config |

config username: 'XX'.

config password: 'YY'

].

Any thoughts on this?

Thanks,

Peter