使用 Ramda 将键的值提升到顶层，同时保留对象的其余部分

Question

我想将它构建到我的 compose 函数中，以便 record 的值到达对象的顶层，而其余键保持完整：

{
  record: {
    seasons: [
      1
    ],
    colors: [
      2
    ]
  },
  tag_ids: [
    2091
  ]
}

我要的结果：

{
  seasons: [
    1
  ],
  colors: [
    2
  ],
  tag_ids: [
    2091
  ]
}

任何键可能或可能不存在。

我一直对在 compose 函数中使用 ramda 方法感到困惑。目前，我正在查看 toPairs 并进行了一些相当冗长的转换，但没有成功。

Answer 1

您可以使用展开运算符。

const startingWithAllProps = {
  record: {
    seasons: [
      1
    ],
    colors: [
      2
    ]
  },
  tag_ids: [
    2091
  ]
}

const startingWithoutRecord = {
  tag_ids: [
    2091
  ]
}

const startingWithoutTagIds = {
  record: {
    seasons: [
      1
    ],
    colors: [
      2
    ]
  }
}

const moveRecordUpOneLevel = (startingObject) => {
  const temp = {
    ...startingObject.record,
    tag_ids: startingObject.tag_ids
  }
  return JSON.parse(JSON.stringify(temp)) // To remove any undefined props
}

const afterTransformWithAllProps = moveRecordUpOneLevel(startingWithAllProps)
const afterTransformWithoutRecord = moveRecordUpOneLevel(startingWithoutRecord)
const afterTransformWithoutTagIds = moveRecordUpOneLevel(startingWithoutTagIds)

console.log('afterTransformWithAllProps', afterTransformWithAllProps)
console.log('afterTransformWithoutRecord', afterTransformWithoutRecord)
console.log('afterTransformWithoutTagIds', afterTransformWithoutTagIds)

Answer 2

这在纯 JS 中可能比 Ramda 更简单：

const data = { record: { seasons: [1], colors: [2] }, tag_ids: [2091] }

const flattenRecord = ({record = {}, ...rest}) => ({...record, ...rest})

flattenRecord(data) //=> {"colors": [2], "seasons": [1], "tag_ids": [2091]}

如果您仍想使用 Ramda 作为解决方案，请考虑查看 R.mergeLeft (or R.mergeRight) and R.omit。

Answer 3

您可以将 R.chain 与 R.merge 和 R.prop 结合使用，通过将键的内容与原始对象合并来展平键的内容，然后您可以省略原始键。

const { pipe, chain, merge, prop, omit } = R

const fn = key => pipe(
  chain(merge, prop(key)), // flatten the key's content
  omit([key]) // remove the key
)

const data = { record: { seasons: [1], colors: [2] }, tag_ids: [2091] }

const result = fn('record')(data)

console.log(result)

<script src="https://cdnjs.cloudflare.com/ajax/libs/ramda/0.27.0/ramda.js"></script>

Answer 4

这可能会有所帮助！

const lift = key => R.converge(R.mergeRight, [
  R.dissoc(key),
  R.prop(key),
]);

const liftRecord = lift('record');

// ====
const data = {
  record: {
    seasons: [
      1
    ],
    colors: [
      2
    ]
  },
  tag_ids: [
    2091
  ]
};

console.log(
  liftRecord(data),
);

<script src="https://cdnjs.cloudflare.com/ajax/libs/ramda/0.27.0/ramda.js" integrity="sha256-buL0byPvI/XRDFscnSc/e0q+sLA65O9y+rbF+0O/4FE=" crossorigin="anonymous"></script>

使用 Ramda 将键的值提升到顶层，同时保留对象的其余部分

Lift a key’s values to top level whilst preserving rest of object using Ramda

javascript

functional-programming

ramda.js