Re: [lennart.borgman.073@student.lu.se: compilation-previous-error fails if first error is at start of buffer]

["Lennart Borgman (gmail)" <lennart.borgman@gmail.com>]

Jan Djärv wrote:

>> The output is from a library not included in Emacs (actually a version 
>> of tidy.el). The output does not have the lines above at the 
>> beginning. It would be rather inconvenient if it had, but maybe those 
>> line still should be there for some reason?
>>
> 
> Yes there is a reason.  Compilation mode uses 
> previous-single-property-change to scan backwards to find the correct 
> position to go to.  But if a line begins at buffer start, there is no 
> property change and previous-single-property-change return nil.
> 
> I think you should modify your library to add an empty line at the top, 
> or maybe some informative text.



Thanks, I modified the libraries a while ago when I realized this. And 
then I forgot about it. No one else seemed to care.

I agree that there is no need to change Emacs behaviour here, but since 
no one understood from the beginning what is going on it might perhaps 
be good to document it.