utility to init object with object with data specification and rubylike getter methods in models (functions constructors)

core.js

var init=function (o, spec){
    for(value in spec){
        if(o[value]==undefined)
            o[value]=spec[value];
    }
};

var getters=function(f, props){
    for(var i=0; i<props.length; i++){
        var mi_get=function(x){
            return function(){
                return this[props[x]];
            };
        }(i);
        f.prototype['get_'+props[i]]=mi_get;
    }
};

test.js

var data_person_example={
        id: 1,
        fname: "Juan Antonio",
        lname: "Ruz",
        DOB: "1976-06-13",
        wage: 100,
        location: "ES"
    };

function Person(){
    getters(this, ["id", "fname", "lname", "DOB", "wage", "location"]);
};

function create_person(spec){
    var p=new Person();
    init(p, spec);
    return p;
}