go - 结构的一个字段，由 3 个项目组成。这怎么编译？

Question

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关闭 3年前。

我见过这样的代码:

type Product struct {
 Name        string         `db:"product_name"`
 Id          int            `db:"id"`
}

type  Stocks { 
 Name        string         `db:"stock_name"`
 Price       float          `db:"price"`
 Type        string         `db:"type"`
}

虽然这段代码可以编译，但怎么可能呢？结构的成员必须由名称和以下类型组成。但是，这里还有 db:"product_name" 这是第三个成员

这怎么可能有效？从 Go 的角度来看，db:"product_name" 是什么？

Answer 1

The Go Programming Language Specification

Struct types

A field declaration may be followed by an optional string literal tag, which becomes an attribute for all the fields in the corresponding field declaration. An empty tag string is equivalent to an absent tag. The tags are made visible through a reflection interface and take part in type identity for structs but are otherwise ignored.