第12行编译报错 : cannot assign to struct field entityMap[“cat”].Value in map 原因是 map 元素是无法取址的,也就说可以得到 a[“tao”], 但是无法对其进行修改。 解决办法:使用指针的map package main import "fmt" func main() { fmt.Println("Hello, World!") type Entity struct { Value strin...
# command-line-arguments .\example.go:22: cannot assign to m.V.(BasicMessage).Length 想在函数中修改interface表示的结构体的成员变量的值,编译时遇到这个编译错误,问题代码如下: package main import ( "fmt" ) type Message struct { V interface{} } type BasicMessage struct { Length int } func t...
今天在编译golang项目时,遇到了一个错误。编译器提示cannot assign to m[1][1] 原项目太大了,不贴了代码大体是这样的 packagemainfuncmain(){m:=make(map[int][2]int)a:=[2]int{1,2}m[1]=a m[1][1]=3} 编译器提示,不能取到m[1][1]的地址。 但是使用fmt能打印出数值 packagemainimport"fmt...
对那些喜欢用nil初始化字符串的人来说,这就是坑: // 错误示例funcmain(){varsstring=nil// cannot use nil as type string in assignmentifs ==nil{// invalid operation: s == nil (mismatched types string and nil)s ="default"} }// 正确示例funcmain(){varsstring// 字符串类型的零值是空串 ""...
cannot use nil (untyped nil value) as parameter of type []string It appears that go/types is wrong here. Per the spec ( https://golang.org/ref/spec#Passing_arguments_to_..._parameters, https://golang.org/ref/spec#Assignability ): If f is variadic with a final parameter p of ty...
操作系统:centos8;golang版本:1.17.4 关键字 const 被用于表示常量,常量的值会在编译的时候确定,常量不能再重新赋值为其他的值。 例如,以下代码会出现一个编译错误:cannot assign to temp (declared const) 定义常量有两种方式:(1) const temp = 1 ,这种情况下temp
不能!倒数第三行报错: cannot assign to struct field list[“name”].Name in map 因为map的value不是指针。首先,map本来存储的就是value的“初始指针值”,可以打印list[“name”].Name, 但不能通过取值的方式来修改。 因为当map扩容时,内部元素会在内存中移动, 移动之后list[“name”].Name获取到的值依然...
Execute go run constant.go to see the result as .constant.go:7:4: cannot assign to b For Loop Examples Loops are used to execute a block of statements repeatedly based on a condition. Most of the programming languages provide 3 types of loops – for, while, do while.But Go programming...
The non-addressability requirement of map index expressions makes sense by itself since we don't want a surviving pointer to a map element. But surely it should be ok to have an invisible temporary pointer p to the respective field which...
q = [4]int{1,2,3,4} // compiler error: cannot assign [4]int to [3]int //切记定义数组时指定的size也是数组类型的一部分,而go又是强类型语言,不同类型不可以直接赋值!!对于函数形参也是如此,所以通常将函数形参定义为slice类型,从而规避数组类型的死板规定。 5. slice (1) 不同slice引用同一个数...