Avoid checking if error is nil repetition?

Question

I\'m currently learning go and some of my code looks like this:

a, err := doA()
if err != nil {
  return nil, err
}
b, err := doB(a)
if err != nil {
  return nil         


        

Answer 1

You can pass an error as a function argument

func doA() (A, error) {
...
}
func doB(a A, err error)  (B, error) {
...
} 

c, err := doB(doA())

I've noticed some methods in the "html/template" package do this e.g.

func Must(t *Template, err error) *Template {
    if err != nil {
        panic(err)
    }
    return t
}