Re: parser.yy / grammar

[David Kastrup]

Knut Petersen <address@hidden> writes:

> Am 24.04.2018 um 21:16 schrieb David Kastrup:
>>
>>>
>>> \version "2.21.0"
>>>
>>> \score{ { c'2     } \addlyrics                      { Hi there }   \layout 
>>> {}}
>>> \score{ { c'2     } \addlyrics   \displayLilyMusic  { Hi there }   \layout 
>>> {}}
>>> \score{ { c'2     } \addlyrics { \displayLilyMusic  { Hi there } } \layout 
>>> {}}
>>> \score{ { c'2 2   } \addlyrics                      { Hi there }   \layout 
>>> {}}
>>> \score{ { c'2 2   } \addlyrics   \displayLilyMusic  { Hi there }   \layout 
>>> {}}
>>> \score{ { c'2 2   } \addlyrics { \displayLilyMusic  { Hi there } } \layout 
>>> {}}
>>> \score{ { c'2 2 2 } \addlyrics                      { Hi there }   \layout 
>>> {}}
>>> \score{ { c'2 2 2 } \addlyrics   \displayLilyMusic  { Hi there }   \layout 
>>> {}}
>>> \score{ { c'2 2 2 } \addlyrics { \displayLilyMusic  { Hi there } } \layout 
>>> {}}
>> Uh what?  How is the output correct?
>>
>
> One, two, or three notes, lyrics as expected. See attached pdfs.
>
> To make things clear:
>
>  * \displayLilyMusic is  a music function, it never is acceptable to 
> \addlyrics in the current version of lilypond
>  * { \displayLilyMusic ... }  is always acceptable because it is a
>  grouped_music_list (but the current parser does not automatically
>  force lyric state)

Nope?  After \addlyrics there is forced lyric state.  That's why a
grouped_music_list is required.  It would be pointless to switch to
lyrics state for a MUSIC_IDENTIFIER since it does not parse differently.

At any rate, we don't implement "features" which we know to fail in a
number of cases because they cannot be done correctly.  It takes an
inordinary amount of work fixing up after people who think "reliable" is
the enemy of "good enough".

-- 
David Kastrup