Teach ramda

ramda_refactoring1.js

const state = [
  {id: 12, foo: 'bar', 'attribute': 101},
  {id: 34, foo: 'baz', 'attribute': 102},
  {id: 56, foo: 'qux', 'attribute': 103}
];

const action = {payload: {id: 34, attribute: 'attribute'}};

// findObjectIndex :: [Object] -> Int
const findObjectIndex = findIndex(propEq('id', action.payload.id));
// removeAttribute :: Object -> ObjectNoAttribute
const removeAttribute = dissocPath(['payload', 'attribute']);

const index = findObjectIndex(state);

const updated = adjust(removeAttribute, index, state);

console.log(updated);

ramda_refactoring2.js

const state = [
  {id: 12, foo: 'bar', 'attribute': 101},
  {id: 34, foo: 'baz', 'attribute': 102},
  {id: 56, foo: 'qux', 'attribute': 103}
];

const action = {payload: {id: 34, attribute: 'attribute'}};

//returns a new array - and remove the attribute of the matching id
let newObject = state.slice(0);
let result = newObject.map((i) => {
    if (i.id === action.payload.id) {
      delete i[action.payload.attribute]
    }
    return i;
}); //return newOject

//Takes an object, and checks if object.id is equal to 
//action.payload.id
const isPayload = R.propEq('id', action.payload.id)

//When isPayload returns true, it returns a copy
//of the object with the specified field removed.
//Otherwise it returns the object unaltered
const removePayloadAttr = R.when(
  isPayload, 
  R.dissoc(action.payload.attribute)
)

let result2 = R.map(removePayloadAttr, state)
 
//Sanity check to ensure the code is doing the same as the original
R.equals(result, result2)