javascript - 具有最终 R.sum 的 ramda 换能器

Question

我试图了解 Ramda 的传感器。这是来自文档的稍微修改的示例：

const numbers = [1, 2, 3, 4];
const isOdd = (x) => x % 2 === 1;
const firstFiveOddTransducer = R.compose(R.filter(isOdd), R.take(5));
R.transduce(firstFiveOddTransducer, R.flip(R.append), [], R.range(0, 100)); //=> [ 1, 3, 5, 7, 9 ]

但是如果我想对结果数组的元素求和呢？以下（仅添加R.sum到R.compose）不起作用：

const firstFiveOddTransducer = R.compose(R.filter(isOdd), R.take(5), R.sum);

Answer 1

我会做这样的事情，只是在初始 0 值之上累积

const list = [1, 2, 3, 4, 5];
const isOdd = R.filter(n => n % 2);

const transducer = R.compose(isOdd);

const result = R.transduce(transducer, R.add, 0, list);

console.log(
  'result',
  result,
);

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