Populate/Provide returns err about inject

[daaku]

IMO returning errors is in fact a very go thing to do :)

Internally when we use inject all our usage is via another package that wraps inject (provides some standard things like loggers, invokes startstop and so on). If you have something like this, it's a good place to put the logic you're suggesting. Also it's trivial to have a method like such:

func must(err error) {
  if err != nil {
    panic(err)
  }
}

Which you can then use like must(graph.Provide(...)) to achieve the same effect.