The yield keyword acts basically as yield return does in C#.
Python uses return for the equivalent of yield break, however that causes an inconsistency where removing yield from a method changes the meaning of the return. Adamant should use either yield break; or yield return; or something else.
Python has yield from for recursively yielding another iterator (Python already used from for other things). A paper proposed yield foreach for the same thing in C#. Adamant doesn't have a foreach or from keyword and isn't likely to get either. Options for this are yield for, yield from, and yield all.