immutability-helper-x

immutability-helper-x

The library extends the kolodny/immutability-helper to support update by path string, like the get/set in lodash.

install

npm install -S immutability-helper-x

usage

import update, { updateChain } from 'immutability-helper-x';

const data = {
  a: {
    b: {
      c: 1,
      d: 2,
      e: [3, 2, 1],
    }
  },
  f: 4,
};

// 1. if you want to update the value of data.a.b, you can
update.$set(data, 'a.b', newValue);
// or
update.$set(data, ['a', 'b'], newValue);

// 2. other methods like push and apply in original update lib
update.$push(data, 'arr', ['car', 'bus']);
update.$apply(data, 'a.b', value => ++value);

// 3. extend method
// step 1
update.extend('$addtax', function(tax, original) {
  return original + (tax * original);
});
// step 2
update.$addtax(data, 'price', 0.8);
// or
update(data, {
  price: { $addtax: 0.8 },
});

// 4. update multiple values at the same time in a chain
const d = updateChain(data)
  .$set('a.b.c', 444)
  .$merge('a.b', {
    d: 555,
  })
  .$push('a.e', [4])
  .$unshift('a.e', [0])
  .$splice('a.e', [[1, 0, 8]])
  .$apply('a.b.d', val => val + 100)
  .value();