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35 lines
763 B
Go
35 lines
763 B
Go
// reflect2.go
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package main
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import (
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"fmt"
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"reflect"
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)
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func main() {
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var x float64 = 3.4
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v := reflect.ValueOf(x)
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// setting a value:
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// v.SetFloat(3.1415) // Error: will panic: reflect.Value.SetFloat using unaddressable value
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fmt.Println("settability of v:", v.CanSet())
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v = reflect.ValueOf(&x) // Note: take the address of x.
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fmt.Println("type of v:", v.Type())
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fmt.Println("settability of v:", v.CanSet())
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v = v.Elem()
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fmt.Println("The Elem of v is: ", v)
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fmt.Println("settability of v:", v.CanSet())
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v.SetFloat(3.1415) // this works!
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fmt.Println(v.Interface())
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fmt.Println(v)
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}
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/* Output:
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settability of v: false
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type of v: *float64
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settability of v: false
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The Elem of v is: <float64 Value>
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settability of v: true
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3.1415
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<float64 Value>
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*/
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