point_free.md

Point-free

So what is Point-free function. Take a look this example:

const getUpdatedPerson = (person) => R.assoc('avatar', getUrlFromPerson(person), person);

To make it as point-free function, we need to get rid of person object we pass into the function.

First way, we can use R.converge:

const getUpdatedPerson = R.converge(
    R.assoc('avatar'),
    [
        getUrlFromPerson,
        R.identity
    ]
)

More detail check part1 and part2

Second way is to use R.useWith:

const countries = [
    {flag: 'GB', cc: 'GB'},
    {flag: 'US', cc: 'US'},
    {flag: 'CA', cc: 'CA'},
    {flag: 'FR', cc: 'FR'}
];

const getCountry = useWith(
    find,
    [
        propEq('cc'),
        identity
    ]
);

const result = getCountry('US', countries);

console.log(result);

So what is the difference between R.converge & R.useWith? Remember this:

• Rule1: if there is only one arg, consider use R.converge.
• Rule2: if there are multi args, consider use R.useWith