Every call of xrand calls .Int() on a fresh generator initialised the same way as the previous one, so it will give the same result. The calls to .Int() in main are all on the /same/ generator, which is updated by each call, so you get three different values.
Chris On 8 May 2017 at 11:26, <sivarajshabin...@gmail.com> wrote: > Hi All, > > Firstly, sorry for the title that sounds like a click bait. I am not > understanding what exactly is wrong with this program > https://play.golang.org/p/Tl0wpaCqK7 > > package main > > import ( > "fmt" > "math/rand" > "runtime" > ) > > func xrand() int { > r := rand.New(rand.NewSource(99)) > return r.Int() > } > > func main() { > fmt.Printf("Version %s\n", runtime.Version()) > fmt.Printf("looks buggy \t1: %d, 2: %d, 3: %d\n", xrand(), xrand(), > xrand()) > > r1 := rand.New(rand.NewSource(99)) > fmt.Printf("Looks fine \t1: %d, 2: %d, 3: %d\n", r1.Int(), r1.Int(), > r1.Int()) > } > > Output>>>> > > Version go1.8 > looks buggy 1: 1108929909, 2: 1108929909, 3: 1108929909 > Looks find 1: 1108929909, 2: 1298032409, 3: 913431059 > > > > When I generate a random number with "math/rand", like the example given in > documentation https://play.golang.org/p/O2k_za0AW7 except that I return the > randomly generated integer from a function, But the function keeps returning > the same value any number of time I call it. On the contrary running the > same code from the main generates random values, there isn't a reason to > doubt rand package. However in the second print statement where random > numbers are properly generated the first value always is the same value > returned by xrand(), here there is something to doubt rand package. > > What am I missing here? Could it be a bug? > > Thanks in advance. > > Cheers > Shabinesh > > -- > 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. > For more options, visit https://groups.google.com/d/optout. -- Chris "allusive" Dollin -- 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. For more options, visit https://groups.google.com/d/optout.
