I understand what is.na does, the issue I have is that its task is not
equivalent to the conceptual task na.omit is doing, in my opinion, as
illustrated by what the data.frame method does.
Thus what i was getting at above about it not being clear that lst[is.na(lst)]
being the correct thing for na
Some relevant information from ?is.na: the behavior for lists is
documented,
For is.na, elementwise the result is false unless that element
is a length-one atomic vector and the single element of that
vector is regarded as NA or NaN (note that any is.na method
for the class of
