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Golang io/ioutil NopCloser


Does anyone have a good or any explanation of Golang's NopCloser function?
I looked around but failed to find anything besides Golang's main doc's explanation of:

NopCloser returns a ReadCloser with a no-op Close method wrapping the provided Reader r.


Solution

  • Whenever you need to return an io.ReadCloser, while making sure a Close() is available, you can use a NopCloser to build such a ReaderCloser.

    You can see one example in this fork of gorest, in util.go

    //Marshals the data in interface i into a byte slice, using the Marhaller/Unmarshaller specified in mime.
    //The Marhaller/Unmarshaller must have been registered before using gorest.RegisterMarshaller
    func InterfaceToBytes(i interface{}, mime string) (io.ReadCloser, error) {
        v := reflect.ValueOf(i)
        if v.Kind() == reflect.Ptr {
            v = v.Elem()
        }
        switch v.Kind() {
        case reflect.Bool:
            x := v.Bool()
            if x {
                return ioutil.NopCloser(bytes.NewBuffer([]byte("true"))), nil
            }