package main
import "fmt"
func main() {
printType(4.0)
}
func printType(i interface{}) {
switch i := i.(type) {
case float32:
fmt.Println("This is a float type", i)
}
}
出于某种原因,此代码未将 4.0
值检测为 float32
,但将其检测为 float64
- 这是为什么呢?我在 win x64 机器上运行它。
最佳答案
For some reason this code does not detect 4.0 value as float32 but it detects it as float64 - why is that?
因为 float64
是 default type对于无类型浮点常量。相关部分强调:
An untyped constant has a default type which is the type to which the constant is implicitly converted in contexts where a typed value is required, for instance, in a short variable declaration such as i := 0 where there is no explicit type. The default type of an untyped constant is bool, rune, int, float64, complex128 or string respectively, depending on whether it is a boolean, rune, integer, floating-point, complex, or string constant.
关于go - 类型开关不检测 float32,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/54045074/