[Feature Request] Shorter error catching

[graarh]

Lets look at the common function

func MyFunc() (*SomeStruct, int, error) {
    data, err := callSomething()
    if err != nil {
        return nil, 0, err
    }
    return data, callSomethingOther(), nil
}

the

if err != nil {
   return <default type value>, <default type value>, err
}

is the most common error checking code. But it can be removed by adding syntax construction like

func MyFunc() (*SomeStruct, int, error) {
    data, <err> := callSomething()
    return data, callSomethingOther(), nil
}

that means if the err is not nil, exit from the function and return default type values except error value. It should not compile if more than one error type returned.

It is pretty clean for reading, and removes a lot of code lines with identical error checking.

[as]

This is a common suggestion, but Go doesn't do things this way. Just use the if statement. If shorter code is your goal, name the returns in the parameter list and use a bare return.

func a() (b, c int, err error) {
   if err = mayfail(); err != nil {
      return
   }
   return 1, 2, nil
}

[minux]

This has been discussed numerous times in the past. Please search the mailing list archive for previous discussions. The short answer is no, we shouldn't add syntax auger for this.

[bradfitz]

Before closing this, let's make sure we have an index of past discussions. Telling people to search the history is convenient but unsatisfying for the OP.

[graarh]

Thanks for the answers, I will search the archive.

[bradfitz]

I filed #18430 for more docs.