@@can.getKeyValue( key )

The can.getKeyValue symbol points to a Map-like object's property accessor function, which returns the value of the object's property with the supplied key. This is only applicable to objects where keyed properties are relevant (like maps).

var map = {
    get: function (key) {
        Observation.add(this, key);
        return this[key];
    }
}

map[canSymbol.for('can.getKeyValue')] = map.get;