Re: What is the deal with define-internal-markup-command?

[Carl Sorensen]

David Kastrup <dak <at> gnu.org> writes:

> 
> 
> Why does define-internal-markup-command have more arguments than
> define-markup-command?  One is the doc, but there also seem to be
> default properties.  Why doesn't define-markup-command have properties
> to specify as well?

define-markup-command is intended for a user to define their own markup
command (which doesn't need to be documented).

define-builtin-markup-command is intended for markup commands that
are part of the LilyPond distribution, so we want to have documentation
for them in the Notation Reference, appendix A-8.

All markup-commands have access to props, which is an alist of properties.
(You can display it from within the scheme, when you write a markup
command.)

The properties arguments that are unique to define-builtin-markup-command
are used to describe in the documentation which properties affect the
builtin markups.

Before we had a way of automatically documenting all of the builtin markup
commands, we only used define-markup-command.  Then somebody (I think
it was Valentin, but I'm not sure) went through and categorized all the markups,
identified all the properties used, along with the default values, and
converted the builtin markup commands to use define-builtin-markup-command.

HTH,

Carl