proposal: Go 2.0 - Allow the _ character to represent the default value for a given return type when returning from a function.

[luke-park]

Go clearly defines what the "default" or "zero" value of a type is, whether it be 0, "", false, nil or whatever. With this in mind, consider the following code snippet:

func GetUserInformationFromEmail(email string) (bool, string, time.Time, error) {
    err := someFuncThatCouldRaiseAnError()
    if err != nil { return false, "", time.Time{ }, err }
    ...
}

I propose that we allow the _ character to represent the default, or "zero" value, of a given type when returning from a function. This would amend the original example to the following:

func GetUserInformationFromEmail(email string) (bool, string, time.Time, error) {
    err := someFuncThatCouldRaiseAnError()
    if err != nil { return _, _, _, err }
    ...
}

This change would reduce time spent checking return types and their default values (when I first started learning Go, returning time.Time{ } for an empty time really threw me). I feel this change would also be semantically meaningful with the current uses for the _ symbol.

[jimmyfrasche]

Potential duplicate of #19642

[mvdan]

This indeed looks like a dup. Let's keep the discussion in that thread. If your proposal has any differences that you think add to the conversation, of course feel free to add them there. Thanks!

[luke-park]

I spent so long looking for something similar to this but limited my results to "return types". I knew there would be a duplicate. Thanks for pointing me in the right direction.