英文:
How to select anonymous field?
问题
从GoQuery中：
type Document struct {
*Selection
Url *url.URL
// 包含被过滤或未导出的字段
}
我想从*Document变量中获取*Selection指针：
doc, e := goquery.NewDocument("http://www.gemalto.com/companyinfo/careers/")
var sel *goquery.Selection = doc // 错误！
sel = doc.(*goquery.Selection) // 也是错误的！
英文:
From GoQuery:
type Document struct {
*Selection
Url *url.URL
// contains filtered or unexported fields
}
I want to get *Selection pointer from a *Document variable:
doc, e := goquery.NewDocument("http://www.gemalto.com/companyinfo/careers/")
var sel *goquery.Selection = doc // error!
sel = doc.(*goquery.Selection) // also error!
答案1
得分: 6
不合格的类型名称充当字段名称
var sel *goquery.Selection = doc.Selection
有关详细信息，请参阅结构类型部分：
声明了类型但没有显式字段名的字段是匿名字段，也称为嵌入字段或将类型嵌入结构体中的字段。嵌入类型必须指定为类型名称
T或非接口类型名称*T的指针，并且T本身不能是指针类型。不合格的类型名称充当字段名称。
英文:
The unqualified type name acts as the field name
var sel *goquery.Selection = doc.Selection
See the section on Struct Types for details:
> A field declared with a type but no explicit field name is an
> anonymous field, also called an embedded field or an embedding of the
> type in the struct. An embedded type must be specified as a type name
> T or as a pointer to a non-interface type name *T, and T itself may
> not be a pointer type. The unqualified type name acts as the field
> name.
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