rambdax/src/evolve.js

Extended version of Rambda - a lightweight, faster alternative to Ramda

import { isArray } from './_internals/isArray.js'
import { mapArray, mapObject } from './map.js'
import { type } from './type.js'

export function evolveArray(rules, list){
  return mapArray(
    (x, i) => {
      if (type(rules[ i ]) === 'Function'){
        return rules[ i ](x)
      }

      return x
    },
    list,
    true
  )
}

export function evolveObject(rules, iterable){
  return mapObject((x, prop) => {
    if (type(x) === 'Object'){
      const typeRule = type(rules[ prop ])
      if (typeRule === 'Function'){
        return rules[ prop ](x)
      }
      if (typeRule === 'Object'){
        return evolve(rules[ prop ], x)
      }

      return x
    }
    if (type(rules[ prop ]) === 'Function'){
      return rules[ prop ](x)
    }

    return x
  }, iterable)
}

export function evolve(rules, iterable){
  if (arguments.length === 1){
    return _iterable => evolve(rules, _iterable)
  }
  const rulesType = type(rules)
  const iterableType = type(iterable)

  if (iterableType !== rulesType){
    throw new Error('iterableType !== rulesType')
  }

  if (![ 'Object', 'Array' ].includes(rulesType)){
    throw new Error(`'iterable' and 'rules' are from wrong type ${ rulesType }`)
  }

  if (iterableType === 'Object'){
    return evolveObject(rules, iterable)
  }

  return evolveArray(rules, iterable)
}