Re: Truncating scroll runs that copy to where we copied to

[YAMAMOTO Mitsuharu <mituharu@math.s.chiba-u.ac.jp>]

>>>>> On Tue, 22 Nov 2011 04:54:28 -0500, Eli Zaretskii <eliz@gnu.org> said:

> If truncation indirectly prevents copying of disabled rows, then I
> think at least a comment to that effect should be in the loop which
> "assigns the rows".  Just looking at the loop, it is not at all
> apparent that only enabled rows are being assigned.

Maybe we can add an assertion as well as such a comment.

>> > Also, what about the unconditional setting of to->enabled_p to 1
>> > in the above loop, regardless of what was that flag in `from'?
>> > Does it look right to you?
>> 
>> In the current code, to->enabled_p seems already be set to 1
>> unconditionally.  Maybe I don't understand the question.

> The question was whether the current code is right when it
> unconditionally sets that flag.  If the `from' row is disabled, why
> should its assignee `to' row be enabled?  If, after your changes, a
> disabled row is never assigned, then `to' will already have its
> enabled_p flag set, by virtue of the assignment.  Either way,
> setting this flag unconditionally after the call to assign_row looks
> bogus to me.  (By contrast, resetting the flag in `from' looks like
> TRT, at least as long as we garble it.)

Ah, I misunderstood that you were proposing setting to->enabled_p to 1
unconditionally.  Yes, maybe we can replace this assignment with an
assertion.

				     YAMAMOTO Mitsuharu
				mituharu@math.s.chiba-u.ac.jp