Questions Regarding Assertions & Capture Group ExtendScript Support

Rick...thanks for getting back to me.  I've spend most of the day experimenting with capture groups (I'll work on lookbehind assertions next week).  I've had some success with the following function:

var find = apple pie;
var replaceString = $2 $1 // change = pie apple
function captureGroups(find) {
    var parts = find.split(/[ -]/);
    var regex = /^(\w+)[ -](\w+)$/;   // Regex to create capture groups
    change = find.replace(regex, replaceString);
    return change;
    }

It handles two capture groups and I can probably adjust the function for 3 or more capture groups (but would have to do it manually).  Optional captures for the first capture group (or prefix) e.g., 
find = '\b(?:apple|blueberry)[- ](pie)'; replace = 'banana $2'; work just fine.  

However, when I try to use optional captures for the second capture group, it doesn't work; e.g.,

find = '\b(apple)[- ](pie|tart|cobbler)  or (?:pie|tart|cobbler), replace = $1$2;  // remove the space or hyphen

finds apple pie, apple tart, and apple cobbler, and changes them to applepie, applepie, and applepie regardless of the second word. 

I'd like to use options in my capture groups for both first capture group and second if that's possible.  Any ideas?