Re: translation-type? vs. backend-type?

[Lukas-Fabian Moser]

Hi David & Jean,

thanks much for the explanations and clarifications!

> > Part b) failed with current LilyPond: "can't find property type-check
> > for `instrument' (translation-type?)" (I'm not sure if a) and c) work
> > or just were not being in an active code path).
> The error message is entirely unrelated to b).  Any correlation must be
> due to different code paths getting exercised.  The problem is that a
> context property "instrument" is being set without being defined, and
> the change flagging the preexisting problem may possibly be
>
> commit e44bc2cc48f9fb714603bdb5f8db532d55374087
> Author: Neil Puttock <n.puttock@gmail.com>
> Date:   Thu Apr 30 20:29:09 2009 +0100
>
>      Add type-checking to \tweak.
>
> in version 2.13.1

Argh, my bad: I wanted to give the english version of the error message 
and searched for it, but then forgot about adjusting to the actual 
message I got. So please forget about "instrument", that's an artifact 
of my stupidity.

The actual warning was:

> Warnung: Eigenschafts-Typprüfung für »mensural_ligature_queue« 
> (translation-type?) kann nicht gefunden werden. vielleicht ein Tippfehler?
> Warnung: Zuweisung wird übersprungen

> > Is this correct? And if so, when did this change between 2.12 and
> > 2.22, seeing as the above code seems to have worked in 2011?
> This has been around since at least 2.7 or longer.  No change here.

Ok, so then I remain unclear as to why the original code seemingly 
worked with 2.12. But at the end of the day, I don't care that much: 
'translation-type it is then, for what should be a \set'table context 
property.

Thanks much!

Lukas