curriedReducer.js

//implementation

//compose, curry, partial
var compose = curry(function(f, g, x) {
  return f(g(x))
})

function curry(f) {
    var length = f.length;
    if (length > 0) return partial(f, length, []);
    else return f;  // f is already curried
}

function partial(f, length, a) {
    return function () {
        var count = arguments.length;
        var arity = length;
        var part  = count < arity;
        var size  = part ? count : arity;
        var args  = new Array(size);
        var index = 0;

        while (index < size) args[index] = arguments[index++];
        if (part) return partial(f, arity - count, a.concat(args));
        var result = f.apply(null, a.concat(args));

        if (typeof result === "function")
            result = curry(result);

        if (arity < count) {
            var args = new Array(count - arity), number = 0;
            while (index < count) args[number++] = arguments[index++];
            return result.apply(null, args);
        }

        return result;
    };
}

//reducer factory
export const hero = (dox,action,state)  => dox[action]?dox[action](state):dox['default'](state)

//curriable reducer factory
export const reducerFactory = curry(hero)