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javascriptfunctional-programmingpointfreeramda.js

Pointfree Join Array to String, by key in object, in Ramda

Can this be done pointfree?

var joinByKey = R.curry(function(key, model){
    return R.assoc(key, R.join(',' ,R.prop(key, model)), model);
});

var input = { a: ['1', '2', '3'] };
var result = joinByKey("a", input); // {"a": "1,2,3"}
Solution

  • Yes, it can be done like this :

    const joinByKey = key => R.over(
    R.lensProp(key),
    R.join(',')
);

const input = { a: ['1', '2', '3'] };
const result = joinByKey("a")(input); // {"a": "1,2,3"}

    If you want to use it uncurrified : 

    const joinByKey = R.curry((key, model) => R.over(
  R.lensProp(key),
  R.join(',')
)(model));

var input = { a: ['1', '2', '3'] };
joinByKey("a", input); // {"a": "1,2,3"}

    The second one works both currified or uncurrified.

    I find it more readable than your version, in contrary of what @naomik says ...