Re: Lilypond error behaviour

[Tim McNamara]

> On Apr 17, 2016, at 3:16 PM, David Kastrup <address@hidden> wrote:
> 
> Noeck <address@hidden> writes:
> 
>> These two are often similar but not always.
>> IMHO, it would make sense to consider both and have 3 categories:
>> - warning: user, please look at this
>> - error: this is severe, there is something definitely wrong, but
>>  Lilypond did its very best to keep running
>> - fatal error: this is severe and Lilypond could not rescue the
>>  situation, nothing was produced
> 
> We are not talking about "nothing was produced" since LilyPond can't
> change the past.  The demand rather boils down to "if LilyPond has
> already successfully produced anything, that should not be left
> available and the PDF should not be completed properly."

Having read this thread from the perspective of a musician who uses LilyPond 
rather than a programmer who is also a musician, I don't don't understand the 
controversy.  It seems to me that LilyPond should produce whatever output it 
can from the syntax such as it is- whether that is a garbled PDF file or MIDI 
file- because that helps point the user to the syntax error in a very concrete 
way.  "Oh, my forced breaks failed there and I see the note with the wrong 
duration that caused it."  For me it is helpful to have the output; having 
LilyPond say essentially "you effed up, son, and you can't have a PDF to check 
it out" is less helpful to me.