There is an important semantic difference between the two, which means you almost never want to use a `Decoder`: `Unmarshal` is for parsing a single json document, whereas a `Decoder` is for parsing a stream of concatenated documents, like so: https://play.golang.org/p/4uiNyJlNIKh. In particular, this means that using a `Decoder` silently drops trailing data and might not detect erronous json: https://play.golang.org/p/cuOAUnKCuEk So, unless you specifically know that you have a stream of concatenated json documents `Decoder` is not actually doing what you want.
On Tue, Dec 29, 2020 at 11:37 AM Amit Saha <amitsaha...@gmail.com> wrote: > On Tue, Dec 29, 2020 at 11:35 AM burak serdar <bser...@computer.org> > wrote: > > > > On Mon, Dec 28, 2020 at 5:22 PM Amit Saha <amitsaha...@gmail.com> wrote: > > > > > > Hi all, let's say I am a single large JSON object that I want to > > > process in my HTTP server backend. > > > > > > I am trying to get my head around if there is any performance > > > advantage - memory or CPU to use the json.NewDecoder()/Decode() > > > mechanism versus the Unmarshal() function? > > > > Unmarshal uses the decoder for unmarshaling. Unless you are planning > > to process the JSON object piece by piece using a decoder, the two are > > identical in terms of performance. > > Thank you for confirming. > > > > > > > > > > Thanks, > > > Amit > > > > > > -- > > > You received this message because you are subscribed to the Google > Groups "golang-nuts" group. > > > To unsubscribe from this group and stop receiving emails from it, send > an email to golang-nuts+unsubscr...@googlegroups.com. > > > To view this discussion on the web visit > https://groups.google.com/d/msgid/golang-nuts/CANODV3%3DU2KRRkvAAEfYqRtCVtYnh2dmGreqePF8QXLo1PriSPw%40mail.gmail.com > . > > -- > You received this message because you are subscribed to the Google Groups > "golang-nuts" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to golang-nuts+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/golang-nuts/CANODV3%3DpXGcHzhSmaLr3f911i2CCYb0_j8CGH7zKAZXd_xTD-A%40mail.gmail.com > . > -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/golang-nuts/CAEkBMfF-MYa0n4vtR6ACu64M2Oegzv_-gKXhAoT3k%3DUSY-XrHQ%40mail.gmail.com.
