Rmail conversion misfeature

Rmail conversion misfeature

[Richard M Stallman]

Querying before converting a Babyl file is misguided feature.
There is no way to proceed except to convert it.

I think the motive for this was to help people avoid
unwittingly rewriting Babyl files in mbox format.
I see the desirability of that goal, but this cure is
worse than the disease.  I plan to delete it.

I can envision a better way to achieve that goal: (1) mark the buffer
unmodified after conversion, and (2) change the operations that would
modify the buffer first warn you and query.  That feature won't cause
any hassles just to look at the file, but when you try to alter it,
you will be notified that this would result in changing its format
when you save the changes.

Re: Rmail conversion misfeature

[Stefan Monnier]

> Querying before converting a Babyl file is misguided feature.
> There is no way to proceed except to convert it.

> I think the motive for this was to help people avoid
> unwittingly rewriting Babyl files in mbox format.
> I see the desirability of that goal, but this cure is
> worse than the disease.  I plan to delete it.

> I can envision a better way to achieve that goal: (1) mark the buffer
> unmodified after conversion, and (2) change the operations that would
> modify the buffer first warn you and query.  That feature won't cause
> any hassles just to look at the file, but when you try to alter it,
> you will be notified that this would result in changing its format
> when you save the changes.

That sounds good.  The only downside I could imagine is if you look at
this file repeatedly without ever modifying it, and it's large enough
that conversion takes a non-negligible time.  Not sure how likely is such
a scenario.


        Stefan

Re: Rmail conversion misfeature

[Glenn Morris]

Richard M Stallman wrote:

> Querying before converting a Babyl file is misguided feature.
> There is no way to proceed except to convert it.

Why not add a defcustom controlling this:

nil                   don't convert, just visit literally
t                     convert without asking
anything else         ask

When asking, it could offer you the choice to set said defcustom to
either t or nil (similar to how unsafe file local variables get handled).

> I can envision a better way to achieve that goal: (1) mark the
> buffer unmodified after conversion, and (2) change the operations
> that would modify the buffer first warn you and query. That feature
> won't cause any hassles just to look at the file, but when you try
> to alter it, you will be notified that this would result in changing
> its format when you save the changes.

That seems a bit complicated.

Re: Rmail conversion misfeature

[Richard M Stallman]

    That sounds good.  The only downside I could imagine is if you look at
    this file repeatedly without ever modifying it, and it's large enough
    that conversion takes a non-negligible time.

If you want to convert the file, it is easy to type commands
that will modify the RMAIL buffer and cause it to be saved.
d u s

Re: Rmail conversion misfeature

[Richard M Stallman]

    Why not add a defcustom controlling this:

    nil                   don't convert, just visit literally
    t                     convert without asking
    anything else         ask

I will not object to offering the current behavior as an option,
but it seems so undesirable that I can't believe anyone would choose it,
so why bother to offer it?

Re: Rmail conversion misfeature

[Stefan Monnier]

>     Why not add a defcustom controlling this:
>     nil                   don't convert, just visit literally
>     t                     convert without asking
>     anything else         ask

> I will not object to offering the current behavior as an option,
> but it seems so undesirable that I can't believe anyone would choose it,
> so why bother to offer it?

Agreed, your proposal is just much better.  As a general rule, asking
questions in `find-file' is not a good idea (tho it's sometimes the best
we can do).


        Stefan