Slice

Read a slice using reflection

main.go

	a := []int{3, 1, 8}
	rv := reflect.ValueOf(a)

	fmt.Printf("len(a): %d\n", rv.Len())
	fmt.Printf("cap(a): %d\n", rv.Cap())

	fmt.Printf("slice kind: '%s'\n", rv.Kind().String())

	fmt.Printf("element type: '%s'\n", rv.Type().Elem().Name())

	el := rv.Index(0).Interface()
	fmt.Printf("a[0]: %v\n", el)

	elRef := rv.Index(1)
	fmt.Printf("elRef.CanAddr(): %v\n", elRef.CanAddr())
	fmt.Printf("elRef.CanSet(): %v\n", elRef.CanSet())

	elRef.SetInt(5)
	fmt.Printf("a: %v\n", a)

Output:

len(a): 3
cap(a): 3
slice kind: 'slice'
element type: 'int'
a[0]: 3
elRef.CanAddr(): true
elRef.CanSet(): true
a: [3 5 8]

Creating a new slice using reflection

main.go

	typ := reflect.SliceOf(reflect.TypeOf("example"))
	// create slice with capacity 10 and length 1
	rv := reflect.MakeSlice(typ, 1, 10)
	rv.Index(0).SetString("foo")

	a := rv.Interface().([]string)
	fmt.Printf("a: %#v\n", a)

Output:

a: []string{"foo"}

Found a mistake? Have a question or improvement idea? Let me know.

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