how to use type switch with reflect.Type?

[Jochen Voss]

Dear all,

For a given variable, say x, a type switch can be used

to execute different commands depending on the

type of x as follows:

    switch value := x.(type) {

    case string:

      ...

    case session.CsrfToken:

      ...

    default:

      ...

    }

Now I came across a situation where the variable is

not given directly but instead is found via the introspection

facilities in the reflect module:

    var valueOfX reflect.Value

    ...

    typeOfX := x.Type()

I would like to use a type switch for this variable.

The best I came up with so far was

    switch valueOfX.Interface().(type) {

      ...

    }

Is there a better way to do this?  What if I only have

typeOfX?  For this case I could only think of

    switch reflect.New(typeOfX).Elem().Interface().(type) {

      ...

    }

which looks clumpsy!  Any better way of doing this?

Many thanks,

Jochen

[buzzlight]

Maybe 

switch typeOfX.Name  {

 ...

}

在 2013年6月5日星期三UTC+8下午5时27分28秒，Jochen Voss写道：

[Rémy Oudompheng]

Use a value switch on typeOfX directly.

Rémy.


2013/6/5, Jochen Voss <joche...@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...@googlegroups.com.
> For more options, visit https://groups.google.com/groups/opt_out.
>
>
>

[Jochen Voss]

Dear Rémy,

On Wednesday, 5 June 2013 12:13:31 UTC+2, Rémy Oudompheng wrote:

Use a value switch on typeOfX directly. 

What would match typeOfX against.  Would the "case string"

from the original example the be converted into the following?

    case reflect.TypeOf(""):

      ...

Or is there a generic way to turn a type as used in a type switch

into a reflect.Type?

Many thanks,

Jochen

[jimmy frasche]

I usually switch on typeOfX.Kind() if I want to check it against primitive types

http://golang.org/pkg/reflect/#Kind