Re: multi-mode editing, including literate Haskell and noweb

[Richard Stallman]

    I don't think there is an easy solution to handle such cases.
    How far the major mode has to look back heavily depends on the
    syntactic state of your code at point (and of course how the
    major mode deals with it).

That is sometimes true.  It means those indentation functions that are
used in multi-mode context would need to be modified to cope with the
presence of interpolated text of other kinds.  They could use the
multi-mode mechanism to find the previous block of text that is of the
same kind, and continue the scan there.

    Worst case may be that all chunks from the beginning of the
    buffer up to point are needed.

Sometimes that will happen.

                                    This is kind of inconsistent with
    the `narrow-to-region' approach.

That's just an approach, not an absolute rule of using multi-mode.
So I think this is a real issue, but not a fatal problem.