Lodash: how simplify

Question

How to simplify next code:

rules = rules.map(x => Object.assign(x, x.ruleOption.options))
rules.forEach(x => delete x.ruleOption)
rules = _.keyBy(rules, 'code')

I start active use the Lodash, and try to understand right using-way.

Answer 1

You can use destructuring with the rest syntax to get ruleOption , and create a new object with ruleOption . You can then use object spread to combine ruleOptions.options with the rest of the object:

 const rules = [{ code: 'x', ruleOption: { options: { type: 'a' }}}, { code: 'y', ruleOption: { options: { type: 'b' }}}]; const newRules = _.keyBy( rules.map(({ ruleOption, ...obj }) => ({ ...obj, ...ruleOption.options })), 'code' ) console.log(newRules) 

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