thought/request for ishandle()

[Ben Abbott]

I've encountered several instances it the graphics m-files where  
handles for figures are verified by

        ishandle (h)

or

        isfigure (h)

Just as often it would be useful to verify a figure represents some  
other "type" of object. Checking for the other object properties would  
also simplify programing.

I'd like to inquire as to opinions of modifying ishandle() to include  
additional property/value pairs. For example the equivalent to  
isfigure(h) would be

        isfigure (h) -> ishandle (h, "type", "figure")

A check for an axes handle

        ishandle (h, "type", "axes")

For a text handle

        ishandle (h, "type", "text")

To find the pair of overlayed axes for plotyy where the

        hax = findobj (hfig, "type", "axes");
        ca = get (hfig, "currentaxes");
	ax = hax (ishandle (hax, "type", "axes", "position", get (ca,  
"position")));

Rather than including optional property pairs with ishandle(), perhaps  
a new function should be written?

        ishandle_with_prop (h, "prop1", value1, "prop2", value2, ...)

In the event of the latter, a m-file can be written (a task I'd be  
happy to take on), for the former the built-in would need to be  
modified.

Thoughts?

Ben