# 实现一个数组去重函数 unique

Issue

欢迎在 Gtihub Issue 中回答此问题: Issue 453 (opens new window)

Author

function unique(arr) {
  if (!Array.isArray(arr)) throw new TypeError();
  return [...new Set(arr)];
}

Author

回答者: guanwanxiao (opens new window)

function unique(arr){
    const map = new Map()
    arr.forEach(value=>{
        map.set(value,value)
    })
    const list = []
    for (let key of map.keys()) {
      list.push(key)
    }
    return list
}

Author

回答者: shfshanyue (opens new window)

const unique = (list) => [...new Set(list)];

Author

回答者: haotie1990 (opens new window)

function unique(array) {
  return array.filter((item, index) => array.indexOf(item) === index);
}

Author

回答者: Vi-jay (opens new window)

function unique(arr) {
  return arr.reduce(
    (acc, item) => (acc.includes(item) ? acc : acc.concat(item)),
    []
  );
}

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