Your example looks just like exceptions to me, just with different keywords
try:
return with_example(fname)
except RecoverableError:
recover(fname)
except Exception as e:
raise ebut if you returned a list you can pattern match on an empty list, a single element list or a list that's longer. which you wouldn't do with exceptions in another language. that's the nice part about `with` that you can stop once you stop matching the pattern and return whatever you currently have, which in the list example may be a perfectly valid thing to return.
with [value] <- Module.some_list_function(arg), # can return an empty list too
[head | tail] = list <- Module.another_func(value), # can return a single element list
longer_list <- Module.takes_multi_element_list(list)
do
longer_list
end
It's about what makes sense for your domain.
I may not be explaining this well so apologies for any confusion