changing genprop.awk to handle radio_values

[John W. Eaton]

On 14-Sep-2007, Shai Ayal wrote:

| As discussed in previous threads, to set radio_properties and/or
| color_properties from an octave_value, an assignment should be
| preformed, not a constructions. i.e.
| 
| radio_property rp("all|none|quiet");
| octave_value ov("none");
| 
| // the right way, preserves the allowed_values
| rp = ov;
| 
| // the wrong way, overwrites allowed values
| rp = radio_property(ov);
| 
| Currently genprops.awk only allows for the "wrong way" when emitting a
| "set" function:
| 
| ##   void
| ##   set_NAME (const octave_value& val)
| ##   {
| ##     set_NAME (TYPE (val));
| ##   }
| ##
| 
| this can be fixed in one of the following ways:
| 1) don't change genprops.awk, and use an o or O modifier to write a
| custom version of set
| 2) make genprop always emit an assignment "set" function:
| ##   void
| ##   set_NAME (const octave_value& val)
| ##   {
| ##     NAME =val;
| ##   }
| ##

I don't think we want to do this in all cases.  The idea was that if
someone defined a set_NAME (const TYPE&) function that did something
extra (say setting the corresponding "mode" property) then that would
happen automatically when calling the version that takes an
octave_value object as its argument, and it would only be necessary to
do that in one place (the type-specific set function that is called by
the octave_value version).

| 3) add another modifier (say "a") to make genprops emit an assignment
| set function
| 4) have genprop.awk automatically emit an assignment "set" function
| (like in example 2) if TYPE is color_property or radio_property

I prefer either 1 or 3.

jwe