Re: penalty -> permission patch

[Joe Neeman]

On Fri, 5 May 2006 18:43, Han-Wen Nienhuys wrote:
> Joe Neeman wrote:
> > First of all, instead of penalty, breakable and page-penalty, we now
> > have: break-penalty, break-permission
> > page-break-penalty, page-break-permission
> > page-turn-penalty, page-turn-permission
>
> sounds good.
>
> > where XXX-permission can be 'allow, 'force or 'forbid.
>
> can you drop the 'allow ? I think it's the proper default, so undefined
> ( SCM_EOL or rather, !scm_is_symbol() ) just means allow.
Actually now that I come to implement this, there is a problem. I can't see 
how to implement \break using only 2 symbols (and '()) because \break needs 
to avoid modifying page-break-permission and page-turn-permission. So I need 
a total of 4 symbols, at least in the BreakEvent: 'forbid, 'allow, 'force and 
'() where '() doesn't change the setting.

I don't think I've explained it very well, but suppose you want to do \break 
\noPageBreak. Then \noPageBreak needs to respect the changes made by \break 
so there must be a symbol that means "don't change anything" to the 
paper-column-engraver.