How to dynamically insert value in a slice

[Jai Kumar]

package main

import "fmt"

var fname = make([]string, 10)

func main() {

        fname[0] = "bar"

        fname[1] = "rok"

        

        name := []string{"john", "ton", "bon", "foo"}

for i := 0; i<len(name); i++ {

  //How to dynamically insert value in to slice fname. Suppose I dont knwo how many elemnts are already present in fname slice already

           //here fname[numbers of elements already there + 1] should start. 

  fname[] = name[i]   // <--THIS FAILS HERE <--

}

for i := 0; i<len(fname); i++ {

  fmt.Println(fname[i])

}

}

How to insert value dynamically in a slice? Please dont assume that we know how many values (it will be alwasy less than 10 though) are already stored in the fname slice already.

[Francisco Souza]

You can use append: http://golang.org/pkg/builtin/#append

--
~f

[Kyle Lemons]

Example: http://play.golang.org/p/9ITq5loJlv 

[Jai Kumar]

Thanks Farncisco and Kyle. Both works well. 

Kyle, your approach is much generic and work well in all conditions (good), but due to my specific need, I modified my code and come up with http://play.golang.org/p/HA2OCAVDkb 

[Uriel]

On Fri, Sep 21, 2012 at 12:14 AM, Jai Kumar <jaiva...@gmail.com> wrote:
> Thanks Farncisco and Kyle. Both works well.
>
> Kyle, your approach is much generic and work well in all conditions (good),
> but due to my specific need, I modified my code and come up with
> http://play.golang.org/p/HA2OCAVDkb

This does exactly the same, but is much more idiomatic code:

http://play.golang.org/p/meA91ACA1T


Also this is a must-read:

http://code.google.com/p/go-wiki/wiki/SliceTricks


Uriel

[Kyle Lemons]

On Thu, Sep 20, 2012 at 3:14 PM, Jai Kumar <jaiva...@gmail.com> wrote:

Thanks Farncisco and Kyle. Both works well. 

Kyle, your approach is much generic and work well in all conditions (good), but due to my specific need, I modified my code and come up with http://play.golang.org/p/HA2OCAVDkb 

I pulled the data that was going into the slice into the gen goroutine so that it wouldn't be possible to cheat.  You specifically said you don't know how many you had beforehand, so I embodied that in my example.  The append was the main point of my code, not the goroutine or the channel.

 

On Thursday, September 20, 2012 3:05:53 PM UTC-7, Kyle Lemons wrote:

On Thu, Sep 20, 2012 at 3:03 PM, Francisco Souza <f...@souza.cc> wrote:

On Thu, Sep 20, 2012 at 6:52 PM, Jai Kumar <jaiva...@gmail.com> wrote:
> package main
> import "fmt"
>
> var fname = make([]string, 10)
>
> func main() {
>         fname[0] = "bar"
>         fname[1] = "rok"
>
>         name := []string{"john", "ton", "bon", "foo"}
> for i := 0; i<len(name); i++ {
>   //How to dynamically insert value in to slice fname. Suppose I dont knwo
> how many elemnts are already present in fname slice already
>            //here fname[numbers of elements already there + 1] should start.
>   fname[] = name[i]   // <--THIS FAILS HERE <--
> }
> for i := 0; i<len(fname); i++ {
>   fmt.Println(fname[i])
> }
> }
>
> How to insert value dynamically in a slice? Please dont assume that we know
> how many values (it will be alwasy less than 10 though) are already stored
> in the fname slice already.

You can use append: http://golang.org/pkg/builtin/#append

Example: http://play.golang.org/p/9ITq5loJlv 

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