Idea for a Go `must()` builtin or `must` keyword.

must.go

// Some functions to demonstrate the idea of must()
func zero() error {
	return nil
}

func one() int, error {
	return 1, nil
}

func two() string, int, error {
	return "two", 2, nil
}


// Without must(), we could do something like this. I do this all the time in initialisation and setup.
err := zero() // no return value except for the error we should check
if err !=nil {
	panic(err)
}

a, err := one() // one return value plus an error we should check
if err != nil {
	panic(err)
}

a, b, err := two() // two return values plus an error we should check
if err != nil {
	panic(err)
}


// With must():
must(zero()) // no return values, panics on error

a := must(one()) // one return value, panics on error

a, b := must(two()) // two return values, panics on error


// Why builtin?
// Because only that way it will fit on any function signature, no matter what the return values are besides the error.
// must() will only accept return values from a function that have at least one error


// Another idea could be to make must a keyword instead of a builtin function. like this:
must zero()
a := must one()
a, b := must two()