小编Sam*_*ats的帖子

当我尝试使用Flask扩展时,我的应用程序会ModuleNotFound在像from flask.ext.sqlalchemy import SQLAlchemy或等行上引发错误from flask.exthook import ExtDeprecationWarning.我安装了Flask和扩展程序.为什么我会收到此错误？

我无法理解 String() 方法如何用于 Go 中的嵌入式结构。考虑一下：

type Engineer struct {
    Person
    TaxPayer
    Specialization string
}

type Person struct {
    Name string
    Age  int
}

func (p Person) String() string {
    return fmt.Sprintf("name: %s, age: %d", p.Name, p.Age)
}

type TaxPayer struct {
    TaxBracket int
}

func (t TaxPayer) String() string {
    return fmt.Sprintf("%d", t.TaxBracket)
}

func main() {
    engineer := Engineer{
        Person: Person{
            Name: "John Doe",
            Age:  35,
        },
        TaxPayer: TaxPayer{3},
        Specialization: "Construction",
    }
    fmt.Println(engineer)
}

这段代码的输出是{name: John Doe, age: …