Re: insert-file-contents and format-decode

[Richard Stallman]

    I currently run this in `insert-file-contents' once around the entire
    call sequence for `format-decode' and `after-insert-file-functions'.

That is the right way.

    Do we want undo boundaries before and/or after the insertion?

An editing primitive such as `Finsert_file_contents' should not make
any undo boundaries.  An undo boundary is made by the main editor loop
and by an explicit call to `undo-boundary'.

    I suppose we do not want to disable the hooks for the "non-insert-file"
    case, for example, interactive uses of `format-decode-region'.  Hence,
    your suggestion to handle undo in `insert-file-contents' implies that we
    have to disable these hooks in `insert-file-contents' too.

Right.

    Finally, I'm completely uncertain what to do about `format-insert-file':
    That function explicitly prompts for a format and does `format-decode'
    after inserting the file and running any `after-insert-file-functions'.
    Shall we treat this is as a sequence of


    (insert-file-contents filename nil beg end)

    (let ((format-alist nil))
       (format-decode-region (point) (+ (point) size) format))

    with _two_ `buffer-undo-list' entries and `after-change-functions'
    calls?

No, I suggest making just one undo entry for the insertion
of the decoded text.  Just as `insert-file-contents' would do.