Functional programming experiment

foo.js

/**
 * Goal: add 10 to each persons age using functions from Lodash and curry only.
 *
 * I have provided a custom version of curry, instead of using _.curry, as
 * the one in Lodash sadly doesn't play nicely here.
 * 
 * Transform:
 *   [ { name: 'Foo', age: 20 }, { name: 'Baz', age: 21 } ]
 * into:
 *   [ { name: 'Foo', age: 30 }, { name: 'Baz', age: 31 } ]
 *
 * Is there a better way than the one below?
 */

var people = [ { name: 'Foo', age: 20 }, { name: 'Baz', age: 21 } ];

people.map(_.pairs).map(curry(_.partialRight(_.map, function (item) {
  if (_.first(item) === 'age') item[1] = item[1] + 10;
  return item;
}))).map(curry(_.zipObject));

function curry(fn) {
  return function (arg1) {
    return fn(arg1);
  };
}

/**
 * I know very little Scala, but off the top of my head, I think
 * this is what it might look like:
 * 
 *   people.map(pairs(_)).map(_.map({
 *     item => if (first(item) === 'age') item[1] = item[1] + 10;
 *   })).map(zipObject(_))
 */

/**
 * Another way of doing it would be to write a custom `transform` function.
 */

people.map(transform('age', function (age) { return age + 10; }));

function transform(key, fn) {
  return function (object) {
    // Immutability by inheritance – delegate to our original object
    var newObject = Object.create(object);
    newObject[key] = fn(object[key]);
    return newObject;
  };
}

Also looking for a way to use functions only from Lodash, if that's possible. It would be nice if I didn't have to write my own curry function.