Which example is better (if ok :=expression; ok)

[telo_tade]

Hello all,

   body, err := record.MarshalToString()
   if err != nil {
      return err
   }

Versus:

var err error
var body string

if body, err = record.MarshalToString(); err != nil {
	return err
}

I cannot tell which one I should be using, as I keep seeing both versions in the same repo.

[mje (Jeff Emanuel)]

The second doesn’t really provide any benefit. Doing the call and test together in the if is useful to limit the scope of the err variable. I follow the first pattern in this situation.

[NobbZ (Norbert Melzer)]

Personally I perfer the second approach, if and only if, I can use := and keep the scope of variables extremely limited.

[amnon (amnon bc)]

first is far more readable.

[Cornos (Oussama)]

If you don’t know follow this simple rule:
If you are initializing an identifier to its zero value use var.

If you want to initialize a value to an identifier other than the zero value use :=