Created
July 20, 2019 07:27
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[Go][Reflect] AssignableTo & ConveribleTo
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package main | |
import ( | |
"fmt" | |
"reflect" | |
) | |
func EnforcePtr(obj interface{}) (reflect.Value, error) { | |
v := reflect.ValueOf(obj) | |
if v.Kind() != reflect.Ptr { | |
if v.Kind() == reflect.Invalid { | |
return reflect.Value{}, fmt.Errorf("expected pointer, but got invalid kind") | |
} | |
return reflect.Value{}, fmt.Errorf("expected pointer, but got %v type", v.Type()) | |
} | |
if v.IsNil() { | |
return reflect.Value{}, fmt.Errorf("expected pointer, but got nil") | |
} | |
return v.Elem(), nil | |
} | |
func main() { | |
i := 1 | |
f := 0.0 | |
pi, _ := EnforcePtr(&i) | |
pf, _ := EnforcePtr(&f) | |
ti := pi.Type() | |
tf := pf.Type() | |
if ti.AssignableTo(tf) { | |
pf.Set(pi) | |
goto finish | |
} else { | |
fmt.Println("Condition I: ", ti.Name(), " can not assign to ", tf.Name()) | |
} | |
if ti.ConvertibleTo(tf) { | |
pf.Set(pi.Convert(tf)) | |
goto finish | |
} else { | |
fmt.Println("Condition II: ", ti.Name(), " can not assign to ", tf.Name()) | |
} | |
finish: | |
fmt.Println(i, f) | |
} |
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