Re: Patch: Syntax and Hard Newlines

[Richard Stallman]

The usual way to solve a problem where two different modes
want to enable a certain feature, and it should only be disabled
when both modes are disabled, is to create two variables
each of which enables the feature when non-nil.  Then each mode
can set its own variable.

This sort of method

    >I suppose it would be cleaner to require minor modes that want to turn
    >on/off `parse-sexp-lookup-properties' in a buffer append/remove their
    >name from/to that variable and kill it iff that list gets empty.

is ok if no simpler method will work.  However, using
`parse-sexp-lookup-properties' this way would require changing all
modes that set it.  We can't reliably do that, since some of them may
not be included in Emacs.

Therefore, it could be better to create a new variable to be used this
way, alongside `parse-sexp-lookup-properties'.  If either variable
is non-nil, then parse-sexp would check the properties.