如果仅更改一种参数类型，请避免代码重复

Question

如您所见，这些功能仅在keys []int和keys []*int（以及名称）上有所不同。func (db *myDB) QueryWithKeys(keys []int) ([]*models.Player) {    var players = make([]*models.Player, len(keys))  _ := db.Model(&players).Where("id in (?)", pg.In(keys)).Select()  // several other equal code here    return players}func (db *myDB) QueryWithPointerKeys(keys []*int) ([]*models.Player) {    var players = make([]*models.Player, len(keys))    _ := db.Model(&players).Where("id in (?)", pg.In(keys)).Select()  // several other equal code here    return players}有没有办法避免这种代码重复？

Answer 1

您可以重新定义方法以接受keys类型参数interface{}以及指示参数底层切片中元素数量的length类型参数，此长度将由调用者提供。intkeys

func (db *myDB) QueryWithKeys(keys interface{}, length int) ([]*models.Player) {

    var players = make([]*models.Player, length)

    _ := db.Model(&players).Where("id in (?)", pg.In(keys)).Select()

    // several other equal code here

    return players

}

有了它，您就可以像这样使用它：

var keys []int = // get list of integers from wherever

players := db.QueryWithKeys(keys, len(keys))

var keys2 []*int = // get list of integer pointers from wherever

players2 := db.QueryWithKeys(keys2, len(keys2))

Answer 2

您可以做的是让 QueryWithKeys 方法调用 QueryWithPointerKeys 方法，然后放入一个指向键整数的指针。明显的缺点是处理时间会更长一些。