high_order_classes_02

var complexHandlePosition = function (a, b, c, d, bounds) {
    ...
};

//a, b are available in aVal, bVal
var easierHandlePosition = _.partial(
    complexHandlePosition, 
    aVal, 
    bVal
);

...
//c and d are available in cVal, dVal
var trivialHandlePosition = _.partial(
    easierHandlePosition, 
    cVal, 
    dVal
);