14 Oct
2019
14 Oct
'19
3:20 a.m.
Failing fast is good, but it is also a very common case to want to add an item to a collection regardless of whether it is set-like or sequence-like. Does the fact that the `append` and `add` methods would still exist mitigate your objection? Call `append` when expecting a list, call `add` when expecting a set, or call `push` or use `<<` when either of those would be appropriate targets.