英文:
Is it possible to do a conversion after assignment?
问题
我想知道是否有任何技巧可以避免使用xv标识符/分配。基本上就像是x, err := T1(strconv.Atoi("1"))这样的东西。
package main
import "fmt"
import "strconv"
type T1 int
func main() {
xv, err := strconv.Atoi("1")
if err != nil {
panic(err)
}
x := T1(xv)
fmt.Println(x)
}
英文:
I'm wondering if there is any trick to avoid the xv identifier/allocation. Basically something like x, err := T1(strconv.Atoi("1"))
package main
import "fmt"
import "strconv"
type T1 int
func main() {
xv, err := strconv.Atoi("1")
if err != nil {
panic(err)
}
x := T1(xv)
fmt.Println(x)
}
答案1
得分: 1
例如，只有x逃逸到堆上，
package main
import (
"fmt"
"strconv"
)
type T1 int
func atoi(a string) int {
i, err := strconv.Atoi(a)
if err != nil {
panic(err)
}
return i
}
func main() {
x := T1(atoi("1"))
fmt.Println(x)
}
输出：
1
英文:
For example, only x escapes to heap,
package main
import (
"fmt"
"strconv"
)
type T1 int
func atoi(a string) int {
i, err := strconv.Atoi(a)
if err != nil {
panic(err)
}
return i
}
func main() {
x := T1(atoi("1"))
fmt.Println(x)
}
Output:
1
答案2
得分: 0
不，我相信没有这样的技巧。
当我想要避免在作用域中声明不必要的变量，并且对于一次性操作时，我有时会使用这种匿名函数调用：
package main
import "fmt"
import "strconv"
type T1 int
func main() {
x, err := func() (T1, error) {
x, err := strconv.Atoi("1")
return T1(x), err
}()
fmt.Println(err, x)
}
另一方面，如果您需要在许多情况下执行类似的转换，并且不一定总是作为相同调用的结果（例如Atoi），您可以创建一个简单的函数，该函数将执行转换并通过错误：
package main
import "fmt"
import "strconv"
type T1 int
func resToT1(n int, err error) (T1, error) {
return T1(n), err
}
func main() {
x, err := resToT1(strconv.Atoi("1"))
fmt.Println(err, x)
}
英文:
No, I believe there is no such trick.
When I want to avoid declarations of unnecessary variables in the scope, and for one-off operations, I sometimes use this kind of anonymous function calls:
package main
import "fmt"
import "strconv"
type T1 int
func main() {
x, err := func() (T1, error) {
x, err := strconv.Atoi("1")
return T1(x), err
}()
fmt.Println(err, x)
}
On the other hand, if you need to perform a similar cast on many occasions, and not necessarily always as a result of the same call (like Atoi), you could create a simple function, which would do the conversion and pass through the error:
package main
import "fmt"
import "strconv"
type T1 int
func resToT1(n int, err error) (T1, error) {
return T1(n), err
}
func main() {
x, err := resToT1(strconv.Atoi("1"))
fmt.Println(err, x)
}
通过集体智慧和协作来改善编程学习和解决问题的方式。致力于成为全球开发者共同参与的知识库，让每个人都能够通过互相帮助和分享经验来进步。
评论